Branching Out Wood

Modern Functional Home Decor by David Wertheimer

Use (or Avoid) the Force!

David WertheimerComment
All of the photos in this blog post are photos of what NOT to do. But I e had a fun time staging them!

All of the photos in this blog post are photos of what NOT to do. But I e had a fun time staging them!

I’ve occasionally heard, both from clients and friends, about horror stories or lack of confidence with tools; many may be scared to use a certain tool, or know someone who has lost a finger (or more) from a power tool.

Indeed, power tools are inherently dangerous: they are designed to transform a very hard material, so have sharp blades, apply a lot of force, etc. With a few key principles in mind, it’s much easier to understand, and therefore, manage the risks. But let me start by sharing my own accident.

Standard legal disclaimer: Do not read this post and think you can use any tool! Be aware of the risks and do not use a tool without understanding how to use it.

Biscuit Cutter, Meet Finger

Skipping over the countless splinters, and the occasional mild burn from swapping a drill bit too quickly, I’ve been fortunate to have suffered only one real accident, with a biscuit cutter.

This was much earlier in my career, when I was woodworking as a hobby rather than a business, so was a little more cavalier both in my thinking and in my care of the tools. I was cutting a slot with a biscuit cutter using a dull blade, holding the wood against the tool by hand instead of clamp or against a fence. The rotation of the dull blade pushed the only thing keeping that blade from my hand - the material - out of the way, and “nicked” the tip of my index finger. That nick could have been a lot worse, but it was pretty nasty nonetheless: it took a small chunk out of my finger, and I wore a bandage for two weeks and my finger was sore for a month, but fortunately, it healed with no lasting damage.

Had I been thinking of “the forces”, I would have realized the stupidity of what I was doing: dull blade or not, this tool is trying to shoot the material sideways out of the tool. So don’t hold the material with your hand behind the blade. Or, a still-stupid but safer approach would be to hold the material by hand with your hand offset from the blade so that, should the material come out, your hand will still be clear of the blade.

This experience, other fears or suggestions I’ve heard in relation to tool safety, and how I personally make sure I’m staying safe, have made me think a little more formally about risks in relation to how the cutting action or force of the tool is pushing against the material.

Most Dangerous: This was how I was using the biscuit cutter when I got injured. The blade is spinning in such a way to pull the board to the right (up, in this photo), which would pull my fingers in toward the blade if the board shoots out.

Most Dangerous: This was how I was using the biscuit cutter when I got injured. The blade is spinning in such a way to pull the board to the right (up, in this photo), which would pull my fingers in toward the blade if the board shoots out.

A little better: Though still dangerous, at least if the board shoots off to the right my hand will likely move away from the blade at the same time. But… this is still a pretty bad setup.

A little better: Though still dangerous, at least if the board shoots off to the right my hand will likely move away from the blade at the same time. But… this is still a pretty bad setup.

Even better, but still not great: No hands are at risk. But the board isn’t clamped to the fence, so it could still shoot out.

Even better, but still not great: No hands are at risk. But the board isn’t clamped to the fence, so it could still shoot out.

Listicle Safety Considerations

First, however, there are some more foundational things to cover. Don’t unplug a tool by pulling on the cord; don’t wear loose clothing or jewelry; check the cord for fraying; don’t use it in the rain; keep the blade sharp, etc.

You can find a hundred online articles with generic (but generally good) guidelines about what to be conscious of in using tools: Here’s one listicle from a company dedicated to providing safety training videos. Great place to start… but also super generic.

Three “general” guidelines I find most relevant for myself are:

There are three bad things in this photo, but the most obvious one is the beer!

There are three bad things in this photo, but the most obvious one is the beer!

  • Keep a clear floor! Though injuries in a workshop can happen from all sorts of things, many can be summarized into two general categories: 1) you contacting the cutting implement, or 2) the cutting implement sending something towards you at high speed. That first type is much more likely to happen if you’re tripping on things on the floor in your workspace. Keeping a clear floor is something I struggle with a workshop full of equipment and projects, but I definitely clear out the space around major tools as I get to work.

  • Don’t drink! This seems easy enough, but during onsite projects, I’ve had more than one client offer me a beer or cocktail, a very nice thought and definitely something I’d be happy to accept - at the end of the day. But not in the middle of the project.

  • Stay focused! I’ll listen to music or podcasts while finishing, sanding, or cleaning - but not while on the table saw. And even when getting into a repetitive task like cutting, say, a hundred coasters, I try my darndest to not let my mind drift.

So… after you read your favorite listicle on tool safety (and the tool instructions), continue on below for slightly more unique content to help keep you safe.

Direction of Force

Think about the direction the tool is “trying” to send the material in relation to yourself. Keeping this in mind should give you much more confidence with some tools and highlight the risks with other tools. Here are some examples, and what that means for guards and risks.

Bandsaw & Vertical Belt Sander

These tools push the material down into the tabletop. This makes these tools fairly safe: they won’t send material flying. But it also means you should never hold an object via hand above the table: the blade or belt will snap it down into the tabletop as you make contact, potentially moving your hand along with the material to some place it shouldn’t be. Need to cut or sand something at an angle? Adjust the table, or build a jig.

Splintered material or hand if the belt grabs onto the material and pulls it flat against the table.

Splintered material or hand if the belt grabs onto the material and pulls it flat against the table.

Even more egregious, as there’s no “if” in this picture: the blade will definitely snap the board against the table when the blade makes contact, pinching your hand or perhaps pulling it into the blade depending on how you are standing.

Even more egregious, as there’s no “if” in this picture: the blade will definitely snap the board against the table when the blade makes contact, pinching your hand or perhaps pulling it into the blade depending on how you are standing.

Disk Sander

A disk sander is pulling the material down into the table on the front edge, and up away from the table on the back edge. So only sand using the part of the disk that is going down into the table top, from the center of the disk out to the front edge. If you contact the back end of the disk, it will send the object flying.

That label with the arrow on top is there for a reason: to remind users which side of the disk to make contact with. Hint: it’s not the one I’m touching.

That label with the arrow on top is there for a reason: to remind users which side of the disk to make contact with. Hint: it’s not the one I’m touching.

Jointer or Planer

Their blades spin such that the material is being pushed back against the direction of the material is being pushed in by you or the feed rollers. So that means never stand directly behind the material as you are guiding a board through these tools; if the drums slip or an uneven board is pushed in, or a board splits, or you lose control of the material, the entire board could come flying straight back out of the machine.

Similarly, if you are pushing material into them, think about the position of your hand and fingers should a board snap back - you don’t want a broken finger or wrist.

In the (admittedly, fairly unlikely) possibility that this board kicks back, it will snap hard against my two thumbs, perhaps breaking one or both. A better position would be to 1) stand out of the way, 2) pushing with just a single hand, so that 3) using fingers or palm in such a way that any kickback would simple just push my hand out of the way.

In the (admittedly, fairly unlikely) possibility that this board kicks back, it will snap hard against my two thumbs, perhaps breaking one or both. A better position would be to 1) stand out of the way, 2) pushing with just a single hand, so that 3) using fingers or palm in such a way that any kickback would simple just push my hand out of the way.

That being said, if you are standing in the proper location, a planer is incredibly safe: the blade is fully enclosed so you’d have to purposely push your hand into it. And well-designed guards on modern machines mean that the sides fully enclose the material when planing thin stock, and at least fully cover the active cutting area even with thicker stock. (A jointer, with an exposed blade, doesn’t benefit from these same safety advantages).

Table Saw

My hands are in a correct position here - and I’m wearing goggles. Good! But I’m standing in the wrong spot - that small offcut could be send back into me at high speed. Admittedly, this has become a real risk here because the over-blade guard has been removed.

My hands are in a correct position here - and I’m wearing goggles. Good! But I’m standing in the wrong spot - that small offcut could be send back into me at high speed. Admittedly, this has become a real risk here because the over-blade guard has been removed.

A table saw blade is also trying to kick the material back towards you; the back edge of the blade is also trying to lift the material away from the table. The exact risks here depends on what and how you are cutting: cross cut or ripping; against a fence or with a miter gage, a large sheet of plywood or a small board. This is why there are splitters (or riving knives), anti-kickback pawls, and guards on table saws - keep these in place if you can! But these guards generally have to be removed to use specialty blades that are commonly in use in woodshops (dado blades, box cutting blades).

In cutting a large sheet or crosscutting a large board by yourself, it can be hard to keep the heavy and unwieldy material square to the blade as you push it through the saw; if it starts to rotate, the side of the blade could grab it.

In ripping a board against a fence, the rotation is less of an issue, but depending on the grain of the wood, the two cut edges of the board that are past the blade might “close up” again past the blade, pinching the blade.

Both of these will send the board or offcut back towards you at very high speeds. Cognizant of this force, then, you should:

  1. Do things to avoid twisting the material. For instance, if you must use a table saw to cut a large sheet, borrow a friend to help keep the sheet straight.

  2. Keep guards in place when you can, or add other guards. The built-in guards help restrain the kickback of the material. Or use a magnetic featherboard - featured in this earlier blog - if you needed to remove some of those guards.

  3. Stand out of the way. If you are using a tablesaw for crosscutting and you can’t keep your hand on both sides of what you’re cutting for whatever reason, don’t stand in front of the “free” end as that side, once cut off, could be sent back into you.

The table saw is probably the most dangerous tool in a shop. Be careful!

Miter Saw

A miter saw (sliding, compound, chop saw, etc.) is trying to pull the material into the fence, away from you (and the back edge of the blade, up).

This makes these saws comparatively safer than a table saw, but that pulling the material towards the fence can cause the material to rotate into the blade if the material isn’t long enough to be supported by both sides of the fence. This rotation can, in turn, pull the hand that is holding the material into the back of the blade if it’s too close to the cut line. So don’t cut very short items without a supporting jig!

I’m cutting a short (~2”) piece a tiny bit shorter and at an angle in this photo - this is bad on multiple dimensions. (1) I have to hold the piece too close to the blade - generally, keep your fingers away from that yellow zone! (2) Because the piece is so short, the end closest to the camera isn’t supported by the fence; the blade, in pulling the piece into the fence, will rotate it into the back of the blade as well. So my too-close hand will be rotated into the blade with the piece. And (2) in cutting the piece at an angle, I’m attempting to just hold the piece at the desired angle, rather than holding it flush against the blade and rotating the miter saw. Great way to lose a finger - but almost certainly, a cut attempted like this will lose the piece!

I’m cutting a short (~2”) piece a tiny bit shorter and at an angle in this photo - this is bad on multiple dimensions. (1) I have to hold the piece too close to the blade - generally, keep your fingers away from that yellow zone! (2) Because the piece is so short, the end closest to the camera isn’t supported by the fence; the blade, in pulling the piece into the fence, will rotate it into the back of the blade as well. So my too-close hand will be rotated into the blade with the piece. And (2) in cutting the piece at an angle, I’m attempting to just hold the piece at the desired angle, rather than holding it flush against the blade and rotating the miter saw. Great way to lose a finger - but almost certainly, a cut attempted like this will lose the piece!

Drill Press

A drill press is trying to spin the material clockwise. If the material is long, extending past the drill press table top, position it so that that potential spinning would slam the material into the drill press column, rather than yourself!

Should the bit grab the workpiece - as big forstner bits like this tend to do - it will rotate the long end clockwise into me. So I shouldn’t be standing in between that long end at right, and the drill press column in the back of the photo. Ideally, the piece should hit (and be stopped by) the column before me.

Should the bit grab the workpiece - as big forstner bits like this tend to do - it will rotate the long end clockwise into me. So I shouldn’t be standing in between that long end at right, and the drill press column in the back of the photo. Ideally, the piece should hit (and be stopped by) the column before me.

And similarly, if you’re cutting something small where you can’t safely apply enough force to keep the material stationary, use clamps or a drill press vice to hold things in place. This is particularly true when drilling into metal - in fact, you may also need to bolt that vice to the drill press table!

Good that I’m using a drill press vice… but bad that it’s not bolted down. In fact, this vice is a recent addition because I neglected to do exactly that.

Good that I’m using a drill press vice… but bad that it’s not bolted down. In fact, this vice is a recent addition because I neglected to do exactly that.

The bent threaded rod on this vice shows the force with which the vice hit the drill press column. Into the scrap heap!

The bent threaded rod on this vice shows the force with which the vice hit the drill press column. Into the scrap heap!

Finally, if you are holding something by hand because you’re confident given the speeds and material hardness, still, do not put your fingers or hands in a place where it will get crushed or severed if you’re wrong! Holding onto a corner of a lamp base by hand while drilling a hole with a relatively slow (250RPM) and sharp Forstner bit may be safe because if the bit unexpectedly snags the wood, it’ll just push your hand out of the way; maybe you’ll get a cut as the base rotates under your hand. But if your arm is wrapped around the base, or your fingers are in some holes in the table, you’ll have a much bigger injury.

When this piece starts spinning - as its almost certain to do with this large Forstner bit - if I don’t release it quickly enough, it will wrap my hand around the shaft. And avoid any temptation to increase your holding power by anchoring your finger through those holes in the drill press table: that will be even harder to quickly pull out of when the piece turns, shearing your finger off in the process. Ouch!

When this piece starts spinning - as its almost certain to do with this large Forstner bit - if I don’t release it quickly enough, it will wrap my hand around the shaft. And avoid any temptation to increase your holding power by anchoring your finger through those holes in the drill press table: that will be even harder to quickly pull out of when the piece turns, shearing your finger off in the process. Ouch!

Table-Mounted Router

A router or shaper is either trying to pull the material away from you or back to you, depending on the side of the bit you connect with. And if you’re using a “spiral” cutter so the bit is like a drill bit (rather than a straight edge cutter), there’s the additional force either pulling the material into the tabletop (which is safe) or pushing it up and away (which introduces additional risks).

There’s too many dimensions to give a quick outline here - this article has some great content. But, given the bit, be sure to think about the direction the material is being pushed or pulled, and what that means for your safety (and for the quality of the cut).

Hand Tools

The examples above are all about floor tools, but you can apply the same thinking to hand power tools as well, thinking not just of the force on the material, but also of the “reaction” force on your hand or arm as you are holding the tool or the material.

Again, don’t let the above be your only safety knowledge! But hopefully it will help you develop some intuition about why there are guards in place and how you can minimize risks when you have to remove those guards or where guards are not possible.

<belt sander>

<domino cutter>

Gloves

DO NOT WEAR GLOVES if there is any risk whatsoever of connecting with a moving part of the machine such as a blade or belt or sand paper! I have heard “why don’t you wear gloves” as a suggestion to avoid the occasional splinter, etc. Of course, I will wear gloves when carrying lumber for exactly that reason. And there are occasions where using gloves with certain tools is either safe or even recommended. But as a general rule, gloves in combination with most wood power tools is dangerous. Do not use them.

Imagine pushing a board through a bandsaw. If the guards are not in place and/or you lose track of where the blade is, your thumb or other finger could contact the blade. Without a glove, and depending on how quick you react and the type of blade, this would be a nasty cut, or maybe even a lost finger.

But if you were wearing a leather glove, the same protection that helped you avoid splinters would also (1) prevent you from realizing as quickly you contacted the blade, while (2) also giving the teeth of the blade something really tough to grab onto, pulling the glove (and your hand or arm) into the blade. The same is true for bandsaws (a tooth on the blade will grab a leather glove and hold it tight, vs. just cutting your finger), a belt sander (a gloved hand can be pulled into the narrow space in between the belt and a table, given a nasty injury instead of just a mild abrasion or burn), … and so on.

Eyes, Ears & Nose

Finally, the most basic safety recommendations of all: wear goggles. And - depending on what you’re doing and for how long - also wear hearing protection and a mask. An hour of sawdust one afternoon might not kill ya, but a full day, for weeks at a time, isn’t good for you. See the Ventilation heading in this post for a bit more about that!

Acknowledgement

Finally, I’d be remiss if I didn’t acknowledge the expert photography of my good friend, Noel Cilker. He got many artistic shots in this photoshoot, but alas, in culling the list into what would make it into this blog, I picked all the more functional shots instead. So, here’s one for you, Noel!

TableSawArtistic.jpg

Tools Tools Tools

David Wertheimer4 Comments

Or, otherwise titled Shop Tour Part V - see parts I, II, III & IV! Another year gone, a few more projects under my belt, and a few more additions to the shop that enabled those projects to go much more smoothly.

That question “Do you work to live, or live to work?” - it could be asked of me, and I’m sure many other woodworkers as well, in a slightly different format with respect to workshop tools and equipment. There’s always something new to add! I’ve long-since run out of floor space, however, so much of what I’ve added is much smaller, hand / cordless tools.

New Toys - errr, Tools

Track Saw

For years, whenever I’ve had to cut a sheet of plywood or other panel good that’s too cumbersome to place on the table saw, I’ve gotten out my straight edge and circular saw.

DWS520SK_2-1000.jpg

This has always been a bit of a pain: the width of the saw “shoe” means that the blade of the circular saw will be a few inches in from the straightedge, so you have to clamp the straightedge offset from the line you want to cut - here’s one guide that outlines that process in detail. That’s fine for an occasional cut, but if you’re doing many, and need to do them quickly and repeatedly, and especially if you want to be able to use the last few inches of a board, this gets old fast.

A track saw is essentially a circular saw with a specially designed shoe that mates with a track you can place right on the wood you’re cutting. The blade comes out right at the edge of the track which has two huge advantages: you no longer need to offset the guide from the desired cut, and the track doubles as a “splinter guard”, minimizing tearout from the blade. That is, it produces cleaner cuts much more easily when setup correctly.

9” Angle Grinder

This was initially for a project for myself, but ended up coming in handy for a commissioned project as well. I have had a 4” angle grinder, great for small cutoffs, but it can’t cut deeper than about 1-1/2”; in building a block wall at my home, I needed something a bit heftier that could go through a 4” block.

grinder.jpg

I picked up this grinder (and appropriate cutting wheels for masonry), and wow this is a powerful grinder. It made getting through that block for my wall relatively easy - but it’s the first tool in a while that made me a bit uncomfortable in its use. Sure, I have many more-powerful-in-absolute-horsepower motors, but this one took attention and care to keep under control - not all grinders are for novices; in 2016, one of Australia’s housing construction agencies recommended contractors avoid using the 9” size for safety reasons.

20180730_124741.jpg

I’ve since used this on a few projects as well where I had to cut some reinforcing structural steel that my smaller grinder would have taken many times longer to cut through. So, I was glad to have it in the shop.

Right Angle Drill

dewalt right angle.jpeg

This one is straightforward and not particularly exciting, but comes in super handy when you need it! This drill allows for drilling holes in tighter spaces where clearance space is at a premium. Need to drill large holes for cables in a cabinet after assembly (or years after installation)? Then this is your tool.

Domino Cutter

Years ago, a friend showed me this tool, and while nifty, I remember wondering why on earth someone would need to spend so much for a tool that doesn’t do anything “special”? Why cut slots for these “dominos”, when it seems to do the same thing as a biscuit joiner? Or if you really need a mortise & tenon joint, why not just cut a mortise & tenon?

Well, my craft has matured, my knowledge has grown, and I need to work a bit more quickly. So I now see the need for a domino cutter, and indeed, in early 2018 a commissioned project required over a hundred of these joints. Essentially, it creates the strength and hidden joinery of a mortise and tenon joint - or more precisely, two mortises that you then fill with precut beech tenons - without the labor of cutting mortise and tenons. I cut those hundred plus joints in a few hours, rather than ten times that!

FS-DOMXX_big.jpg

This isn’t a tool for every shop as it’s kind of pricey (as are all Festool tools), but either for specific projects, or if you do a lot of fine joinery, it is just amazing.

Soldering / Desoldering Station

Switching gears a bit to the electrical side, I build a lot of electrical stuff that require soldering - Lamps with in-line dimmers that need to be soldered; USB LED-strips; and perhaps most intricate of all, the controllers and sockets for the Nixie clocks.

Previously-used 1960s-era Nixie tube sockets that need some desoldering (and some repair)

Previously-used 1960s-era Nixie tube sockets that need some desoldering (and some repair)

Up until recently, I’ve been relying on a relatively good soldering iron, but it had its limits. Though it was adjustable, it wasn’t temperature controlled; it was low powered so took a while to heat up to a useful temperature; and it wasn’t that great for desoldering my occasional mistake. Given my backlog of assembly in early 2019 - four Nixie boards of one style, a dozen in another style, many many power & LED cords - that would mean at least seven full days in front of the soldering iron already in the schedule. And more throughout the year. Time to upgrade.

Desoldering Station.png

There were lots of combo tools out there - with built-in testing power supplies, with built-in lights, with combination desoldering vacuums and hot air guns. Given the desoldering I also do to make some of the vintage electrical parts useable, and the heat-shrink tubing for the LED cables, I decided to invest in this three gun Aoyue “repair station” (and a work lamp and solder fume extractor).

Three full days into my electrical work - one day desoldering Nixie tube sockets and two assembling boards - I’m amazed with this workhorse, and wish I had had it much earlier.

Work Van

This isn’t really a tool, but an acquisition for my business which became critical as I got more larger cabinetry commissions. But it will also simplify my life for the wine & art festival circuit: my Kia Soul EV had a lot of cargo space, but it was a PITA to load & unload as I did consecutive shows but needed to use my car in between. And strapping all the pop-up tent, tables, etc. to the roof always scared me a bit with the sunroof in my car; in fact, after two years of that, the sunroof stopped working.

20181213_095808_HDR.jpg

So, time for an upgrade. This van is perfect, not an overwhelming vehicle, but sporting a roof rack for plywood sheets and raw lumber, and enough space inside so I no longer need to use the roof for shows. And space enough to bring a few more things to the shows - namely, a higher more-comfortable chair for me!

Wish List

Wow my shop is chock full. Maybe space for a few more hand tools as pretty much all of these were, but between the growing range of raw materials I need and the growing set of projects in progress at any point, keeping it organized is a constant challenge.

There are still a few tools I’d love to add, but which will probably wait until I get a far larger space. Anyone nearby to me in South San Francisco have these tools handy that they’re happy to let me use periodically?!

Drum Sander

I’ve started doing a few end grain products - as in a few of the coaster designs. Though those were initially inspired as a way to use up a lot of scraps, I really enjoyed both the process of making them, and the finished result. I’d like to do some larger end grain products, and finish-sanding them is a huge amount of work, especially since you can’t run those through a planer. Or at least, you shouldn’t - sure, it can be done, and many have done it successfully by a combination of luck and better practices (only take a 32nd of an inch off at a time, etc.), but it’s much more prone to destroying the product, the blades, the planer, or your hand than planing the face grain.

A drum sander can rough or finish end grain products; a drum sander won’t destroy expensive blades if there’s a tiny bit of dirt or a buried brad nail; a drum sander will get you an even smoother finish on planer-surfaced boards. And you can get more width per dollar in a large drum sanding machine than a large planer. Oh how I’d love access to, say, this machine - but at just under a ton, and needing a 65A 3-phase power supply, it just isn’t going to happen.

Maybe if I can find a better way to organize the tools & materials I already have, I’ll end up adding a mini 12” version, or even better, the open-ended 18” one allowing me to sand up to 36” wide boards:

Larger Planer

shelix.jpg

My Dewalt planer - for which I sung the praises for a year and a half ago - is still a workhorse in my shop. However, it has a few limitations: it can only plane boards up to 13” wide, and it has “standard” straight-edge blades. The latter I’m in the process of addressing with an upgrade to a “shelix” helical cutting head. But I can’t upgrade the width; periodically I need to work with wider boards. I’d love to add a 20”+ planer, … but at a ton (and nearly $10k!), it also won’t be happening.

Fortunately, it’s infrequent enough that I’ve generally hired the services of an outside shop. But if I need to do more… I’ll either have to turn down that work or get me a big planer!

Whats on Your Wish List?

I’ll confess for all the cool and fun (and expensive) tools I’ve added, given the number of switches and plugs I wire, one of the best time savers - and certainly the best bang for the cost! - was this automatic wire stripper, an ingenious creation of mechanical engineering.

So great tools need not be big or expensive - what cool gadget or workhouse is on your wish list, big or small?

Ode to Recycling

David Wertheimer1 Comment

I try my darndest to recycle (and reduce and reuse), but last weekend, I got some warm fuzzies due to a series of exchanges with folks both online and in the real world.

My current set of “raw” walnut tealights are made from San Jose walnut, but as those have been strong sellers, I’ve been looking for some more walnut cutoffs or logs. Via Craigslist, I found a woodworker in Albany who had partnered with an arborist to find better uses for “good” wood than the compost heap. He had the better part of a tree in his driveway, and I picked up a few logs for free, which will get me through another season.

After these logs dry out for about a half year, they’ll find new life …

After these logs dry out for about a half year, they’ll find new life …

… as these tealights or something similar.

… as these tealights or something similar.

Odd shapes of scrap hardwood - what to do?!

Odd shapes of scrap hardwood - what to do?!

I’ve been collecting growing bins of beautiful “good” scrap wood - everything from walnut & oak, to wenge & padauk. Even a little bit of teak! It’s too nice to compost. Though I’ve delivered some to fellow artists who do wood jewelry, this listing hasn’t done too well, so it has been accumulating for years! Oakland’s Depot for Creative Reuse - a gem for artists, school projects, and ideas - couldn’t use it, so on a lark, I brought it to Urban Ore, a much more industrial size (and style) business in Berkeley whose goal is to “end the age of urban waste”. I hadn’t even handed the bins off when a shopper - thinking I was purchasing those for myself - exclaimed “I want those! Where did you find them?” She teaches arts and crafts to 4 -5 year olds on the East Bay, and was excited for all the colors and shapes. Those giant boxes didn’t stay at Urban Ore for long!

And finally, in looking for a new home for three barrels of “bad” scrap wood - cut down pallets, construction grade pine, unusable shims, and so forth - I found someone advertising that he’ll gladly take old wood fences, 2x4s, etc., as he turns them into his own art & furniture. Unfortunately, my remaining scrap wouldn’t work for him, but it made me happy to find an artist turning what many would haul to the dump, into beautiful pieces.

There’s a market for just about everything! So when you’re about to toss something into the trash, think twice - might someone else put it to use? A few avenues to consider other than the dump:

  • Sell it on Ebay

  • Drop it off at Goodwill or Salvation Army

  • Drop it off at Urban Ore or East Bay Depot for Creative Reuse

  • Sell it - or give it away for free - on Craigslist

  • Recycle? Compost?

Other Handy Calculators & Resources

David WertheimerComment

In the last two posts, I delved into two important considerations for good wood design, sag and moisture; though the math is aided by a lot of handy online calculators, those topics have a lot of theory and equations, and can - at times - be messy and an inconvenience to think about.

In this post, I’ll share a few resources, and yes, some calculators, that help with much simpler topics that are still great to keep by your side as a woodworker. Hopefully, by putting all these in a single post (well, three, if you include those earlier posts), it’ll be super useful to all the burgeoning woodworkers out there.

Am I missing any key resources or calculators? Let me know - always love to learn more!

Weight

How much does wood - or other building materials - weigh? That’s not typically relevant for the lamps or vases or coasters. But for a large coffee table I’ve designed, or to provide some specs to a client about a table before I build it, that does come in handy. I’ve also used some of these resources to figure out how much gravel - or how many blocks - to order for some gardening and remodeling projects I’ve undertaken as well.

There’s no single source for the weight of everything; every page has its own unique focus:

Hardwood: How much do different hardwoods weigh? The data is provided in pounds per cubic foot; there are twelve boardfeet in a cubic foot.

Plywood (and other engineered sheet goods): How much weight is going on the roof of my vehicle when I transport 11 sheets of 3/4” plywood to a job site? (Short answer: too much!) This has plywood of different thicknesses, as well as MDF, OSB, etc.

Dimensional Lumber: How much do 2x4s weigh? How ‘bout if they’re “green” or pressure treated?

Glass: Does that coffee table or dining room table have a glass top? How much weight does that add - or does the structure need to support?

Angle Iron: While there’s lots of different steel (or other metals) you could incorporate into a project, this is the most common I’ve used to add structural rigidity; this site (host of the angle iron sheet) has a lot of other great data sheets on all the sizes / types of metal shapes & materials they sell.

Masonry / Gardening: OK this isn’t really for woodworking, but figured I’d throw it in the list as much so I could find it easily in the future! How much will that 15 cu ft of gravel weigh? How ‘bout the block wall?

a Rendering.png

Though I often refer to one or two of these in larger projects, the most complicated project I’ve worked on so far, a 3’ by 4’ coffee table, had me referring to four of these to come up with the finished project weight of 355 pounds (!!!):

  • 49# of solid walnut for the sides of the coffee table

  • 114# of walnut-veneered plywood for the top, bottom, and internal structure

  • 25# of steel for structural rigidity

  • 11# of solid wood for the foot / table supports

  • 62# of glass for the top

  • 94# of brass for the 88 USPS mailbox doors

Cut List

Do you have a large cabinet project that you’ll be fabricating out of sheet goods (i.e.: plywood) and want to figure how many sheets to use? Or do you have a lot of random strips and partial sheets left over from previous projects and want to make best use of those? Then check out the CutList Optimizer.

I’ll confess I haven’t used it much as many of my larger projects have actually been fairly easy to optimize due to the fact that there’s only one or two standard widths of the boards I’ll be cutting. But for a few more-complex projects - again, with that coffee table, and expensive walnut plywood as the material that I didn’t want to overbuy - this came in handy.

And the tool is pretty darn comprehensive, compensating for blade kerf, and also grain orientation if its not being painted. And it’s smart enough to only produce cuts that can in fact be done with a table saw, panel saw, or track saw. That is, no crazy puzzle piece cuts where you’d have to stop mid-way through a cut - it’s not just “simply” a geometric bin-packing algorithm (which already is a research dense area that has supported many a graduate student).

CutListOptimizer.png

Books

Any list of resources would be sorely lacking if it didn’t include some great books on woodworking as well! There are, of course, literally thousands of books out there, covering everything from furniture restoration to project ideas to basic techniques. But a few excellent references I’ve come across:

Understanding Wood: A Craftsman’s Guide to Wood Technology: Bruce Hoadley’s 1980s book, with content and images updated in 2000, is an excellent reference material covering a topic sorely lacking in almost all the other woodworking books you find out there: wood as a material. That is, it doesn’t touch on all the amazing things you can build with wood, but - as the title says - how to understand the properties of wood. And sure, there are good books on trees as plants, but those leave the connections to what woodworkers care about similarly untouched.

This covers how trees grow (and the implications of that on knots, strength, water retention, etc.); strength properties of lumber and boards and how those relate to humidity and wood orientation; how tools work on the material, etc. Though it gets slightly academic at points, it’s excellent for those who want to understand the “why” of lots of rules of thumb and guidelines - many wrong, misguided, or incomplete - you might hear from others in a workshop or read in passing on a website.

The Wood Database: Both a website and a book, Eric Meier started this project in 2007 as he tried to navigate incomplete and inconsistent online and print books about wood properties. It’s grown to a database of hundreds of species, with high resolution photos, and consistently-presented properties related to strength, weight, hardness, and shrinkage. And the online version has a nifty search feature where you can identify species by inputting one or several properties.

Moisture & Wood Movement

David Wertheimer2 Comments

Continuing with the theme of wood engineering topics - the last post was about how to avoid sagging shelves - here I’ll touch on the basics of how moisture effects wood, and what to do to minimize that impact.

No, I’m not talking about wood decay and rot that the homeowners among us suffer in our siding and patios. That’s “simply” avoided by keeping that fine furniture dry. Rather, wood expands and contracts with changes in the atmospheric humidity. In Understanding Wood, Bruce Hoadley estimates that the seasonal change in humidity in the average U.S. climate for a two-story wood-framed house can change the height of a house by 3/4”!

But for many smaller “products”, the dimensional changes might be imperceptible either in absolute size or even in relative size. Nonetheless, even imperceptible changes can tear a beautiful piece of furniture apart if it’s not well designed to account for that movement; this earlier post on veneering showed one such picture. Or you may have noticed the impact with the drawer or door that sticks in summer but moves freely in winter.

In short, wood moisture content depends on the humidity. And wood size depends on wood moisture content. This can be a long and complicated topic, but I’ll boil it down to a few key points, and a handy online calculator!

Background in Layman’s Terms

Trees are collections of very long cells. When the tree is growing, those cells have water in them, and the cell walls also have water. The weight of water in a species in comparison to the completely dry version is called the moisture content (MC) - for instance, a board weighing 20# when freshly cut may only weigh 12# after it is fully dry, which yields a moisture content of 8# / 12# = 67%. Hardwoods have moisture content from 60% - 100%, but can range from 40% to 160% depending on species and where in the tree is being measured.

EMC vs RH.png

Wood bought from the lumberyard is typically dried - whether in a fast process in a kiln or more gradually by exposure to atmospheric air over years - to a moisture content level of 8-14%. That removes all of the water inside the cells, but leaves some water between the cells. However, the wood is gradually reacting with the environment, absorbing or releasing water. Though it differs slightly by species and a few other attributes, there is a relationship between relative humidity (how much “free” water is in the air) and the “equilibrium” moisture content (EMC) of the wood - that is, the moisture content at which the wood will not absorb or release more moisture.

But let’s back up for a moment - where is this moisture stored? Well, it’s stored where there already is some remaining moisture, in the cell walls. And because those cells are really long along the direction the tree grows, the effect of adding or removing water is somewhat akin to raking up autumn leaves with a steel-tined rake: it may get a little wider as leaves push the tines apart, but it doesn’t really get any longer.

Similarly, wood expands in the radial and tangential directions, but not really much in the longitudinal direction. In fact, that “3/4” inch” that a wood-framed house might grow or shrink in height isn’t at all because of the height of the vertical framing members, but due almost solely to roughly 38” thick of joists, top plates, sole plates, and subflooring in a two-story structure; a typical 8’ tall 2x4 installed might shrink only 1/16th of an inch even from a “green” fully saturated state to average 8% MC - so this direction of movement is insignificant and typically ignored in movement calculations and construction considerations.

So there’s a difference in shrinkage between the horizontal axes of the tree (which we need to be concerned about) and the vertical axis of the tree (which we can ignore). In fact, its a bit more nuanced: the expansion is larger in the tangential direction than in the radial direction. This is thought to be because of internal structures in the wood, but regardless this difference can be a relatively modest 1.4x in black walnut, or as much as 3.0x in California laurel.

How do you know if you have radial or tangential axis on the face of a board - or both? Though sometimes you may know from how the board was initially cut from the log, there is apparently some confusion among the terms quartersawn and riftsawn. So the best way to tell is to look at the board itself, observing how the growth rings cross the surface or the end.

Acknowledging that these terms might be somewhat inconsistent among different sources, in the diagram here, Plain Sawn boards will exhibit tangential shrinkage; Quarter Sawn primarily radial shrinkage (and so the most dimensionally stable); and Rift Sawn somewhere between the two.

Acknowledging that these terms might be somewhat inconsistent among different sources, in the diagram here, Plain Sawn boards will exhibit tangential shrinkage; Quarter Sawn primarily radial shrinkage (and so the most dimensionally stable); and Rift Sawn somewhere between the two.

So How Much Does it Expand & Contract?

How much wood moves depends on the seasonal fluctuation in relative humidity of the environment the wood is in, the wood type, and which axis of wood (tangential or radial) we are focusing on. You can find tables of tangential shrinkage (St) and radial shrinkage (Sr) percentages, such as here or in the Wood Database; these are the % shrinkage in that dimension from fully saturated to oven dry (i.e.: 0% MC). However, as shrinkage does not occur as the cell cavities dry out - shrinkage only occurs as the cell walls dry - and the cell cavities are empty only at approximately 28% moisture content, this is essentially the percent shrinkage in that direction as the wood changes from roughly 28% MC to 0% MC. And just to introduce a little more terminology, that 28% is called the “fiber saturation point”, or fsp.

We can roughly approximate* that shrinkage as linear as the MC of the wood changes. So we now need to just know the seasonal variation in relative humidity, use that to get to the seasonal variation in EMC. The equation is: width * shrinkage % * (delta EMC / fsp). Just to aid in intuition, the term (delta EMC / fsp) is essentially what fraction of the total possible range over which the loss in moisture content causes shrinkage is actually experienced by the board.

Putting it together in an example, the shrinkage of a 9” wide plain sawn yellow birch board from summer to winter is:

  • Width: 9”

  • Shrinkage percentage: plain sawn implies we should use tangential shrinkage percent; for yellow birch St is 9.2%

  • Delta EMC (equilibrium moisture content): this depends on the change in relative humidity in the region; fortunately, the USDA Forestry Products Lab has put together a map to aid here, reproduced below. For the San Francisco Bay Area, we should use 8% in January to 13% in July, for a delta of 5%. Some parts of the country have a range of as small as 1%; others experience a range as great as 6%. And if a piece might be taken around the US (or the world), it should be able to handle a range of 9%.

  • fsp: varies slightly between species, but 28% is generally a good-enough value to use for hardwoods

usda foresty products lab map.jpg

Putting it all together, that 9” poplar board in summer will get narrower by 9” * 9.2% * 5% / 28% = 0.148” in winter. That’s 1.6%, or nearly 5/32”.

* This approximation has an error of about 5%, which is small enough to be good for almost all applications, but when real precision is needed, refer to a more complex formula in Chapter 6 of Understanding Wood. And I’ve skipped over a few other details, such as the assumption that the board you’re working with is already at the EMC, and the EMC of your environment falls within the EMC of the environment where the piece will live. But hey, in a short blog post, some concessions must be made.

The Shrinkulator

Oy vey. That’s a lot to think of. Well, fortunately here there’s a handy online calculator that automatically pulls up the right data for different wood species and does the calculation. You still need to figure out where on the map you are (or the finished piece will be), and which dimension is radial or tangential. But the rest is done for you. Check out the Shrinkulator here.

Shrinkulator.png

So What?

Wood moves - so what? Well, a few examples are given at the top: sticking door, or the split coffee table. But there are two general potential problems from this movement:

  • The actual dimensional change

  • The uneven change in surfaces

buckle.jpg

Anyone who has done a wood floor - whether solid hardwood or engineered - has heard that the materials must be delivered and left onsite to “breathe” for a few days before installation; this is to acclimatize the planks to the on-site humidity so that there is less sideways movement that would open up gaps or cause buckling. This movement in floors is also less problematic in narrower planks as the more frequent gaps allow for a little more expansion or allow gaps to be spread amongst more lines, making them less visible. This flooring contractor highlights six common hardwood floor problems, and five of them are caused by movement-related moisture before, during, or after installation.

Or the uneven movement in a joint can cause problems as well. While just about every piece of furniture mates different faces of wood together, two common joint and construction techniques highlight the potential issues here:

Mortise & tenon joinery: Common in chairs, doors, and lots of furniture, a rectangular or round tenon fits snugly into a mating slot or hole cut for the mortise. If this is very snug when the wood is drier, say in winter, it’s attempt to expand in summer will be constrained by the lack of movement of the mortise (as that mortise will not grow in height with a change in humidity). This constrained expansion may deform the tenon so that, in winter when it shrinks again, it breaks the glue line and draws away from the earlier tight fit.

Mortise &amp; tenon joinery

Mortise & tenon joinery

Rail &amp; stile panel door

Rail & stile panel door

Rail & stile panel doors: Doors - for your kitchen cabinet or for your front door - may be of a rail and stile construction technique with solid wood panels. In short, the rail and stile form a channelled frame into which the panel can be inserted; a beginner woodworker may cut the panel to fit snugly in the channel. If the panel fits snugly in winter, as it expands in summer, it will burst or crack the frame. Or if the panel fits snugly in summer (and is then painted or finished after assembly), as it shrinks in winter, unfinished edges of the panel will start to show along the border of the panel.

As an interesting aside, wood movement is the reason plywood always has odd numbers of plies (or layers). Each ply is placed perpendicular to the previous one and would exert force on the face along the direction of the larger movement. An odd number allows those forces to cancel each other out.

There are countless other ways that movement can be a problem. For a piece to last for generations, a good woodworker will need to take movement into account in their craft.

How to Manage Movement?

Bruce Hoadley outlines five basic approaches in Understanding Wood: preshrinking, control moisture, mechanical restraint, chemical stabilization, and good design. While each of these is a book (or several) in itself, I’ll touch on them briefly here:

Preshrinking: Don’t work with green (freshly cut undried) wood! Green wood is useful in some circumstances - bending for instance. Typically, however, if you’re buying lumber from Lowes or from a specialty lumber store, it comes pre-dried, whether by kiln or air. But also - as the examples of hardwood floor issues above highlight - the wood may need to further acclimatize to your specific environment, particularly if it has been stored outside, unsheltered from the elements.

Control moisture: Unless the piece is museum grade, you’re probably not going to keep it in a hermetically sealed environmentally controlled box. But you can do a lot to retard moisture exchange with the environment, reducing the extremes in moisture content the piece would achieve at the shorter-duration extremes of humidity we might experience environmentally, by the application of a good finish. Different types of finishes vary in their ability here, so do a little research. And you can be mindful of the humidity you’re exposing the piece to, exerting some environmental controls (humidifier, dehumidifier) at the extremes which aren’t just good for your furniture, but also your comfort.

Mechanical restraint: Steel or plastics bolted to the wood can help restrain the wood - but depending on how much the wood needs to move, this could actually bow the wood between the bolts, bend plastics, or rip the bolts out! This technique is more commonly associated with plywood, where plies with perpendicular grain orientation are glued to each other to form a thicker panel. Douglas fir, for example, has tangential shrinkage of around 7.7% and longitudinal shrinkage of 0.1%; a plywood panel constructed of perpendicular plies of this has shrinkage (along both dimensions) of 0.5%, practically eliminating movement considerations.

Though plywood is often thought of as an ugly building material, there are beautiful architectural grade hardwood-veneered plywoods out there, far less expensive (and stabler and easier to work with and better for the environment) than the corresponding amount of hardwood. Just for rough numbers, in 2019, you can get a 4x8 3/4” sheet of a) construction-grade plywood for $30; b) casework-grade oak or maple plywood for $60; or c) architectural-grade walnut plywood for $250. With architectural grade, the veneers are bookmatched, consecutive, and defect free.

Chemical stabilization: Polyethylene glycol (PEG) or wood plastic composite (WPC) are two chemical approaches to stabilizing wood, though only the first is somewhat accessible to the small-shop woodworker. PEG essentially replaces the moisture in a green or fully-saturated board with a polymer of automobile antifreeze which does not evaporate, keeping the wood at its saturated dimension. I’ll confess I have no experience with either approach so will direct you to a google search to learn more!

Good design: This is where we often have the most control, between material selection, joint design and grain direction in the mating pieces, dimensional adjustments you can make (which may or may not be visible in the finished product), etc.

For a rail and stile cabinet door, for instance, a panel made of plywood won’t cause problems. Or if the design and profiles demand solid wood, a) sizing the panel small enough to allow for expansion without cracking the frame, b) finishing the panel before final assembly, and c) gluing the panel only in the center of the top & bottom rails can eliminate the problem; that’s how it’s been done for hundreds of years before the invention of plywood!

Mortise Example.png

For a mortise & tenon joint, splitting a round tenon allows for a fracture line to occur inside the wood rather than at the glue line; or redesigning the joint to allow for two smaller-width tenons rather than one wider tenon makes the joint stronger in multiple ways, including halving the amount of expansion a single mortise has to accommodate.

Also, as the tangential face expands faster than the radial face, which expands faster than the longitudinal direction - flipping the boards, where possible, so that the rates of expansion are most closely aligned helps. In this diagram, we would ideally want the mortises cut in the tangential face and the horizontal board with the tenons to have the tangential face on the side. That way, the movement left-to-right is identical (if the boards are of the same material). And additionally, the vertical movement of the tenons is the smaller tangential expansion, to more closely align with the non-movement in the longitudinal axis of the vertical direction of the mortises.

For something like a solid wood countertop or tabletop anchored to a steel or composite frame - such as a hanging vanity in a bathroom - you would want to screw in the back solidly, but allow for horizontal movement by creating oval slots for the holes along the side. A 24” deep maple countertop may shift as much as 3/8” along its tangential axis. Or - if you don’t have an easy way to create oval slots in steel, just drill larger holes and use washers for the screws.

This is just a scratching the surface of good design for wood movement, and I’m only a novice here. But hopefully this has gotten you thinking about some of the considerations, either as a woodworker yourself, or in better knowing what to ask about or the language to use in working with a fine craftsmen in the field.

How to Avoid Sagging Shelving

David WertheimerComment

Most of the smaller stuff I build is not “structural”, nor does it use a lot of material. But the bigger pieces - from built-ins to free-standing furniture - has to hold up to its own weight as well as years of use (and abuse).

How do we make sure those shelves don’t sag, or the floating countertop is solid? In this first post I’ll share pointers to several useful calculators, and touch on good guidelines and a few techniques to avoid finding yourself with a beautifully crafted piece of furniture that, under duress, starts looking like this!

image017.jpg

How Much Sag is Too Much

You will probably notice deflection far before it gets to the sorry state of that coffee table! 1/32″ (0.03″) per running foot, or 3/32″ (0.09″) for a 3′ wide bookshelf or table, is typically visible.  And over many years, the sag of a shelf tends to increase by as much as 50% as it is stressed repeatedly in the same direction. So a good target for initial allowable sag is 0.02″ per foot or less.

Don’t Worry About Small Shelves

Many cabinet designs call for the flexibility of adjustable shelves. Unfortunately, however, adjustable shelves are more prone to sagging than fixed shelves, as anyone who has loaded a cheap Ikea bookshelf with all of their college textbooks can attest. This is a consequence of many factors in that $50 hand-me-down bookcase. But with a bit more planning and design consideration (and better materials), sagging can be wholly avoided.

However, for “small” shelves, sag is not really a problem and one can just ignore considerations of sag for typical loads. What’s “small”? The most frequently used quality materials for custom-built wood shelves are 3/4” thick plywood, poplar, or pine; definitely avoid the melamine-laminated composite shelving and MDF. And a typical shelf load to plan for is 20-40# per foot - libraries often plan for 35#.

A 30” wide adjustable shelf that is 10” deep, made of any of these three (plywood, poplar, pine) materials, will have an acceptable sag for a load of up to 35# per foot, or about 90# for the entire shelf. Make it of poplar - the stiffest of those three materials - and you can make a narrower adjustable shelf, down to about 8”, still without any problems. Deeper or shorter shelves? Or anticipating less weight? Sag definitely won’t be a problem for those small adjustable shelves.

Narrower shelves aren’t as strong, however. But fortunately, as you get narrower, it’s less likely that you’ll get to 35# per foot. A 6” deep adjustable shelf will probably not get loaded more than about 20# per foot - made of any of those materials, a 30” span would still be fine.

Of course, if you’re loading your shelves like that coffee table above, all bets are off!

The Sagulator

Wood Bin’s Sagulator wood sag calculator

Wood Bin’s Sagulator wood sag calculator

But - what if the design calls for something outside these “small” shelf guidelines? Higher weight capacity, or longer or narrower shelves? Then, it’s time to break out a calculator. But don’t worry - these are online calculations that hide the messy math, at least to start out with!

I’ve come across a few calculators online, but the Sagulator seems to be the best one so far for ease of use, flexibility, and options that allow for common solutions that woodworkers use to counteract sagging shelves. Select the material, enter a few numbers, and voila, it estimates the total and per foot sag, and even makes a judgement call, summarizing the results as one of Excessive, Borderline, or Acceptable.

Counteracting Sag

If your design sags too much, there are a few simple solutions, and a few more involved design changes. Let’s assume, however, that changing the size of the shelf, and how much load or weight you need it to support, is not an option.

For the examples below to give a sense of how much each design change can help, let’s focus on a 10” deep shelf, made of 3/4” thick plywood shelf. And let’s assume a typical 30# per linear foot load. Then we can find the maximum width shelf that will give an initial sag of 0.02” per foot.

Different Material

Some materials are just stiffer than others. Of the three most common for basic shelving - poplar is the stiffest, with pine and plywood just slightly less stiff (or, in engineering-speak, having a lower modulus of elasticity). However, switching to even less elastic (and more expensive) oak could push your design into safe territory; if the shelves will be painted, the material choice is almost irrelevant except for cost (and availability).

  • Pine (spruce): 28”

  • Plywood (fir): 28”

  • Poplar: 28”

  • Oak: 32”

If budget is no barrier, a beautiful hardwood like purpleheart is even stiffer, and could get you a 35” wide shelf, but that would be a very unconventional (and wasteful) use of that expensive wood!

Thicker Materials

Though Lowes or Home Depot only carries boards in 3/4” thickness, and plywood thicker than 3/4” is not very common, you can usually find thicker materials at a specialty lumber store. If you go to 1” thick material instead of 3/4”, that gets you another 10” or so of width.

  • Pine (spruce): 38”

  • Plywood (fir): 38”

  • Poplar: 41”

  • Oak: 42”

Edging Strip

Cosmetic edging strip

Cosmetic edging strip

An edging strip - typically, a solid piece of wood - can be fastened to the front edge of a shelf. Occasionally, this may be strictly a cosmetic element, such as that applied to the sides of a plywood shelf in order to “finish” the edge. If it’s the strip is no thicker than the shelf itself, it doesn’t really add any strength to the shelf.

However, when made thicker / taller, it often helps the shelves blend in more seamlessly to the rest of the cabinet system and show more heft and mass. The edging strip can be of the same material or a different material - often the shelf will be a dimensionally stable and inexpensive plywood, and the strip might be a slightly more expensive solid wood like poplar. See styles #1 & #2 in the diagram below for examples of a recessed edging strip and flush edging strip.

And that edging strip also need not have just a simple rectangular shape; it could be rounded, have a beaded profile, or… the imagination (and available router bits) is the limit.

That adjustable plywood shelf that sags 0.02”/foot when 28” long could be extended to:

  • 34” with 3/4” thick by 1-1/2” tall poplar edging strip (most common size and material for paint grade)

  • 35” with same strip made of oak instead

  • 37” back to poplar, but 1-3/4” tall instead of 1-1/2”

Fixed Shelf

Is that still not a wide enough span? If we’re talking about furniture, countertops, or similar, a steel structural element may be the way to go. But if that’s not an option due to cosmetic or other reasons, really the only option left is to make those shelves fixed instead of adjustable. A shelf that is fixed - whether by glue, screws, a dado cut, or a combination of these methods - is held at a right angle to the upright, whereas a shelf that is resting on pins or brackets can flex much more easily.

Sagging Shelves.jpg

Shelves that are also fixed to the back of the cabinet (style #4 in the diagram below) add additional strength to the shelf as well.

Three styles of adjustable shelves (#1 - #3), and three styles of fixed shelves (#4 - #6).

Three styles of adjustable shelves (#1 - #3), and three styles of fixed shelves (#4 - #6).

Shelves fixed only at the two ends such as for an open see-thru display cabinet, or due to limits on how the cabinet is being constructed, there are more strict limits to the width of the shelf.

Returning to the earlier example of a plywood shelf without any edging strip, that 28” span could expand to a 48” span if the two ends (but not the back) were fixed instead of adjustable - shelf style #6 in the diagram above.

Or put all these things together: shelf fixed at the two ends, made of 1” thick oak, with a 1-3/4” tall 1” wide oak edging strip. That get’s you an 84” wide shelf that would easily support 30#/foot, or 210# in all, without any visible sagging.

Embedding Steel

Finally, we get to the idea of embedding steel. This is generally not an option for built-in shelves because the steel might be unsightly in traditional wood cabinetry, and a standard 3/4” thick board does not provide enough depth for a meaningful steel element to be embedded. But for other types of furniture, this might be able to be hidden - or perhaps could even add to the aesthetic.

Steel has a whole bunch of other considerations, and these are all beyond the capabilities of the Sagulator. So read on…

Shape & Weight

Steel is available in loads of shapes…

Steel is available in loads of shapes…

There is probably a few semesters of university level mechanical engineering here, so I’ll stay away from the theory. But in short, hollow shapes like a square, round, or rectangular tube, an I-beam, or even just an “L”-shaped “angle iron”, give a lot of strength without taking as much weight as a solid shape.

And the more solidly the steel is affixed to the element it’s supporting, the more effective the combined system will be in resisting forces. I recently installed a solid maple hanging countertop to hidden / embedded steel angle iron by screwing it in every 4”. Or liquid nails or a similar adhesive can be liberally applied along the entire length.

These are all great guidelines and help provide some intuition, but we want to get to something a little more concrete.

Steel Sag Calculators

Because of the range of shapes and sizes that steel can be purchased in - and the fact that it is a more uniform material used in a greater range of critical structural designs - there are many calculators that unfortunately are not as user friendly as the wood-focused Sagulator.

This is the best calculator I’ve found so far, but it requires a few additional inputs that take some effort to find or calculate.

  • Modulus of elasticity: this is a property of the material, such as steel or copper. The default value is a good starting point; this table lists a few other metals.

  • Load on the beam: this value represents the center-loaded weight for the entire shelf; typically the shelf or beam would have a uniform weight distribution. A center load puts more stress on an element than a distributed load so designing for this would be very conservative. And the value expected here is the load over the entire shelf, not the load per unit length.

  • Moment of inertia: this is a property of the cross-section of the steel, such as a hollow tube or angle iron; this site allows you to select the shape, and then enter the key dimensions of the shape; be sure to use inches, to match the only units supported by the “Easy Calculation” tool. The moment of inertia resisting sag is the value in the “Moment of Inertia Ixx (unit^4)” field.

The CivilEngineer website has plenty of moment of inertia calculators for most common shapes

The CivilEngineer website has plenty of moment of inertia calculators for most common shapes

Supporting the Shelf on Three Sides

What if the shelf is supported on three sides, rather than two? In my projects, this has come up as potential elements to calculate in a few designs. Two recent examples:

  • How much might a “floating” bathroom countertop sag (secured at the back and two ends), given it has a very heavy concrete sink?

  • Can we get a very wide adjustable shelf, that would sag too much if only supported on the two ends, but perhaps could become possible if we put some adjustable pins in the back of the cabinet as well?

And the first of these questions ended up being irrelevant: even with a ultra-conservative 300# load, the 2-1/4” thick maple countertop would sag less than 0.01” per foot, according to the Sagulator. In fact, we could almost double the length before sag becomes an issue. Add to that the fact that it would be fixed to the back as well as the two ends, and this one will definitely not sag.

eFunda Calculator Fail

The eFunda (Engineering FUNDAmentals) three sided supported plate steel sag calculator

The eFunda (Engineering FUNDAmentals) three sided supported plate steel sag calculator

However, if we needed to calculate this sag for a countertop (i.e.: shelf) fixed on three sides, this calculator comes close to helping.

The main difference in the second question is that the sides are adjustable or “simply supported” in engineering speak, rather than fixed. This calculator comes close to answering the question where the sides are not fixed.

For both, the required inputs include the modulus of elasticity, touched on earlier, as well as the poisson ratio for the material. For woods, the modulus of elasticity for many species can be found in The Wood Database, an excellent website (and print book). The poisson ratio is a bit harder to come by, though chapter four (Mechanical Properties of Wood) of the Wood Handbook, a USDA publication available for free as well as in print, lists the values for some species. It turns out the results aren’t very sensitive to the poisson ratio (so long as the value is around 0.3).

Both these “three side” calculators have three major issues, however, that limit their applicability:

  • if the length of the shelf is more than 4x the width, the results come with a warning that the approximations used may not work for this problem; indeed, I got some non-intuitive results with a shelf length 6x the width.

This doesn’t instill confidence in the results.

This doesn’t instill confidence in the results.

  • some species poisson ratios are far outside the 0.3 around which the calculator is fine-tuned

  • want to use it for more than three or four calculations? you better sign up for an account!

Fusion360 Fail

But wait! Fusion360, in which I do all of my photorealistic rendering, and much of my CNC designing (see this blog entry), does robust engineering analyses. Granted, it isn’t as straightforward as a calculator, but for those larger projects with structural uncertainty, it is probably worthwhile to model and verify, rather than to find out too late the design will fail.

In writing this blog, I got so excited by this solution that had been lurking on my laptop all along, so I designed a simple but super wide adjustable shelf to test it out, putting in a few different options for how many pins to provide for back support over the 5’ span.

Sag analysis problem.png

This screenshot of the results shows what would happen if the shelf were made of ABS Plastic. Or I could choose any of a variety of other plastics, copper, one of dozens of steel grades, or other metals and engineered / refined products.

A shelf made of polystyrene just won’t cut it!

A shelf made of polystyrene just won’t cut it!

But no wood species can be modeled - the material properties aren’t defined in Fusion360. Or more specifically, at present, only isotropic materials can be modeled. That’s a fancy way for saying that wood strength depends on the direction of the grain, which is far more difficult to model than uniform materials like plastics and metals.

Opportunity for Future Online Tool

So it seems this is an area where - at least at present - detailed analysis will depend either on a (typically in the low thousands of dollars or more) professional structural engineering evaluation, or more likely given that high cost, intuition and overdesign to avoid potential problems.

Do you have a structural engineering background? Want to conquer this area for all posterity to benefit? I’d love to partner with someone to make a new calculator available to the woodworking community!

Is Using Wood Bad for the Environment?

David Wertheimer3 Comments

This post is motivated by a number of conversations that have made me think about the potential contradiction in my environmentalist tendencies and my using wood as my primary medium. Paraphrased for brevity:

  • Friend#1: "You put up solar panels, yet you cut down trees..."

  • Friend#2: "Most people don't know where the 'material' of trees comes from..."

So, here’s my attempt to square this circle.

How much wood is harvested annually?

It's tough to come by well-vetted (and current) stats, but here's a few from Wikipedia:

  • The worldwide growing "stock" of forests is about 434 billion cubic meters (2005).

  • The annual wood harvested for all purposes is about 3.5 billion cubic meters (1991), though estimates of wood used for burning have wide ranges. This represents about 0.8% of the growing stock.

  • The annual "roundwood" (officially counted wood not used as firewood) harvested is 1.5 billion cubic meters (1998).

How much is a cubic meter? If you're familiar with your typical eight foot 2x4, there's about 100 of them in a cubic meter. An average 2000 square foot house uses the equivalent of roughly 1875 2x4s for framing, so that means that was enough wood harvested in 1998 to frame 80 million comfortable homes.

Desk+Gold.jpg

Translating that to my business - I purchase wood by the "board foot", which is one square foot of lumber 1" thick, or one twelfth of a cubic foot. Big projects - such as the 24 oval mirrors for the Southern California carousel rebuild - use a few hundred board feet (about 1 cubic meter).

However, most of my small products, such as this popular lamp, use between a quarter and a half of a board foot. So you could make 150 of them from a cubic meter of wood - or in 1998, if I had cornered the wood market, I could have made 225 billion of these lamps, enough for every person on the planet to have about 30!

But just saying I don't use much ain't much of a defense. So, is using wood good?

What's the alternative to wood?

If you want a lamp, or some coasters, or a shelf, you could purchase something made of plastic, or glass, or any of a hundred other materials. And many of these materials don't involve cutting down a tree. But, many of these materials are far worse for the environment overall taking into consideration all of the “embodied energy” and “embodied carbon” that goes into creating an object.

Said another way, though it’s always better to consume less, if you are going to consume, do it with goods that take less energy to create, and leave less of a carbon footprint on the planet.

Illustrative breakdown of the stages of a product or material life that should be considered when understanding the carbon footprint.

Illustrative breakdown of the stages of a product or material life that should be considered when understanding the carbon footprint.

That's one reason why I'm happy to say that my workshop (and my vehicle) is powered by solar energy; while that's just a small piece of the overall ecosystem, that also reduces the environmental footprint of what I sell.

For a much more scientific and detailed analysis of hundreds of materials commonly used in construction and elsewhere, check out this paper. For example, the average sawn hardwood has about 7-10% the energy per kilo that the typical plastic contains, and about a quarter of the embedded carbon.

In fact, wood has a far lower embodied energy and carbon content than almost every other material that might be commonly used for home decor. So while it’d be better to not purchase anything at all, if you do, use wood!

Is burning wood "bad"?

I periodically host a bonfire to get rid of scraps I accumulate - primarily construction-grade framing wood, but also occasionally scrap hardwood that I just can't find a home for in either my own projects or via with my fellow artists.

This produces soot & ash which isn’t great for the local air quality but - on a small scale from limited camp fires and bonfires - has fairly modest impact. In larger scales, however, there are clearly bad effects: Northern California briefly took the crown of having the world’s worst air quality in mid-November due to the tragic Camp Fire; breathing the unfiltered San Francisco air for a day then was equivalent to smoking a half pack of cigarettes.

Battling the Camp Fire, Nov 2018

Battling the Camp Fire, Nov 2018

Or - not quite as tragic but just as bad for our health - lower-income regions that rely on wood for cooking and heat have very bad air quality, as I personally witnessed in parts of the Himalayas in mid-October. For this reason, it seems parts of China - including Tibet - have outlawed wood stoves, and the U.S. EPA has similarly banned inefficient wood burning stoves a few years back.

But beyond that, does this contribute to global warming, or other types of air pollution?

Goodbye, failed early attempt at a round coffee table, c. Nov 2017.

Goodbye, failed early attempt at a round coffee table, c. Nov 2017.

Wood treated with anything (paint, insect protection, stains), or composite wood products (plywood, particle board, etc.) is a definite no-no, for the very bad toxins that this releases into the air.

But how about "raw" untreated wood? Logs you've cut down from your property, that old pallet sitting in your backyard, or some wood scraps? You may have heard wood referred to as a "renewable" or "carbon neutral" resource - how is this so, if burning it releases CO2 into the air?

That's because that carbon in the tree came from the atmosphere in the first place, as the tree grew from a seed. Trees breathe in CO2, and breathe out O2, in the process called photosynthesis - those “C” carbon atoms, over time, become the "wood" that is the tree. So while the bonfire alone isn't carbon neutral, in the relatively short lifespan of the tree, the growth-to-bonfire process is carbon neutral. And if you didn't burn it, as the tree decomposed over time in your backyard or in a landfill or as mulch, it would release the same CO2 back into the atmosphere.

Compare that to burning fossil fuels, which prior to combustion were sequestered deep underground, and would have stayed there if not for their extraction. One could say that over the time horizon of millions of years it took the oil to form to when it was ultimately burned, that too is carbon neutral! But over the few hundred years that we have existed as an industrial society, however, this is not carbon neutral. That additional carbon sits contributes to global warming (or gets absorbed by the ocean, acidifying the water, or having other deleterious effects on our global environment).

Is this the Final Word?

Wood is better than many alternative materials. And at least from a carbon neutrality perspective - though not from a localized air pollution or a deforestation perspective in certain regions - wood is an acceptable fuel. But that’s not to say we can cut down all the trees: cutting down one tree from a forest is different from harvesting the entire forest!

Indeed, there’s a lot more to responsible harvesting for forest management. Entire organizations exist to help manage, educate, police, and certify producers. And - spoiler alert! - it has nothing to do with “raking the forests” of leaves, as Trump ignorantly claimed in a recent conversation. Trees - like animals, and ecosystems in general - can also become endangered or at risk. All of these will be topics I cover in future posts.

Is there a particular environmental concern you have with forestry management, or consuming wood products? Email me or leave a comment - I’d love to hear your thoughts.

Woodcarving with a Nepalese Master

David Wertheimer2 Comments

I was in Nepal in most of October, hiking through the Himalayas, munching on momos, and enjoying the local culture. One thing that is quite visible as I wandered around the Kathmandu valley was that there’s a long tradition of amazing wood carving in the architecture.

Each window and door jamb and lintel has amazingly detailed Newari carving.

Each window and door jamb and lintel has amazingly detailed Newari carving.

A typical Newari window; photo credit to Osman Khawaja

A typical Newari window; photo credit to Osman Khawaja

First, a brief ethnic background. Nepal is a country of many ethnic groups - the two biggest groups compose less than 30% of the population and there are 18 groups that comprise more than 1% of the population each! The Newari are one such group, just under 5% of the population as of 2011.

The Newari are the historical inhabitants of the Kathmandu Valley and its surrounding areas in Nepal, and are major contributors to the artistic and cultural community in the densely populated Kathmandu Valley. Among their many artistic contributions are the elaborately carved wooden windows, a distinguishing feature of traditional Nepalese architecture. The artistry reached its peak in the mid-18th century, visible on palaces, private residences, and sacred houses.

Though many historical sites - and the Kathmandu Valley region in general - suffered immensely in the 2015 earthquake as the traditional local architecture is primarily made of brick, many of the homes and buildings with these amazing carvings are still standing today. A few very talented master carvers are helping to recreate those pieces, restoring those devastated older homes, as the stretched-thin budget of Nepal allows.

This ain’t “redtagged” - its still used as a home

This ain’t “redtagged” - its still used as a home

A much more obvious collapse, waiting for reconstruction

A much more obvious collapse, waiting for reconstruction

The leaning walls of many homes - and quite a few temples - are temporarily (since 2015!) reinforced

The leaning walls of many homes - and quite a few temples - are temporarily (since 2015!) reinforced

Via Backstreet Academy - a website that connects travelers directly with artisians and local tour guides working for themselves in Nepal, Cambodia, Laos, and elsewhere in Southeast & South Asia - I connected with one of those skilled craftsmen, Heera Ratna Bramhacharya, for a four-hour one-on-one class in his home & workshop.

Practicing carving straight lines, more difficult than I expected to keep it at the same depth!

Practicing carving straight lines, more difficult than I expected to keep it at the same depth!

Heera is an amazingly patient instructor - after taking me through a few basics and an introduction to the handtools, I practiced on one side of a small plaque before doing the “final” carving of a Nepal “sign” on the other. In addition to selling pieces in his small shop - about half to tourists and half to locals - he supplements his income with these small and one-on-one classes, as well as aiding in some of the rebuilding efforts.

My finished piece. Though I’m happy how it turned out… I think I’ll stick to my current area of expertise!

My finished piece. Though I’m happy how it turned out… I think I’ll stick to my current area of expertise!

Originally from Bungamati - a village about 7 miles from the center of Kathmandu - Heera learned woodcarving from both his grandfather and father. And in addition to teaching tourists like myself for interest, he also teaches local women who supplement their family income by carving small ornamental strips for him that he then incorporates into his larger pieces.

Small Embedded Window.jpg

What took me four hours to carve, he probably would have whipped out in 15 minutes - he mentioned he could carve the majority of (the central portion of) one of these smaller windows in a day, and he typically does a 10 hour day carving, sitting cross-legged on the floor. (After 30 minutes, both my legs had fallen asleep and I couldn’t stand anymore!)

While smaller pieces were fairly inexpensive, don’t get planning too much ahead: for those looking to incorporate one of these amazing windows into a coming remodel, something like this might cost about USD$20,000!

This bay window set on the upper floor might cost $20,000! Extra for the “peaceful” dog.

This bay window set on the upper floor might cost $20,000! Extra for the “peaceful” dog.

"Do you miss the office job?"

David WertheimerComment

In sharing my story with both fellow artists and customers at the weekend art shows, I am often asked if I miss my former “day job” at Google - while my story isn’t unique, it definitely isn’t commonplace either. And never is this more top of mind than when I’m in Mountain View, as I was earlier this month for their fall Art & Wine Festival, as I run into many former colleagues and current “Googlers”.

Given that it’s now been a full two years since I regularly went into the office, this is as good a time as any to share some reflections on whether the fears I had at the time I made the leap became real, what I miss (and what I don’t), and other musings for those considering pursuing a similar leap.

But in a word: NO! I definitely do not miss the office job - hopefully all the posts of the past two years have made clear how much I’m enjoying my new gig, though it does have its challenges. Nonetheless, there are certainly some elements of the tech world that I do miss.

My (Unfounded) Fear When I Left: Laziness

I was worried that, with my newfound freedom, I might sit on my ass and watch TV all day, pursue a few interests for a few weeks or two months, read a few books, and then have nothing to do, nothing that fulfills me or makes me happy.

Laziensss.jpg

Those who know me well will probably tell me this was never a real risk, but taking such a major leap - when Branching Out Wood wasn’t yet set up - was a little scary.

Turns out that, even without a 9-5 (or more realistically, 7:30-6:30p) day job, there still ain’t enough time in the day to do everything I want to, between this business and attempting (and failing) to get another business off the ground, volunteering, and yes, of course, reading a bit more. And indeed, travel has become more easy: I have taken a few family and personal trips I probably wouldn’t have done before, and am about to embark on a trek through the Himalayas.

So, nope, laziness was not a problem - I still don’t “relax” or “lounge” very well!

An Unexpected Challenge: Social Interaction

However, there is one challenge I did not anticipate: lack of social interaction. Sure, I probably have roughly the same social life in the evening and weekends now that I did when I had the day job.

But the day job was also very social. There are continuous water cooler interactions and lunchtime conversations that one friend described it as a “slow running soap opera”, where you feel connected to a wide network of colleagues’ kids and family drama, pets and remodels, commute woes and exciting travels well beyond your core group of close officemates.

Contrast that with my day job now: most days I’m working in my workshop, a solitary affair. Weekend festivals and social interaction during commissions make up for that a bit - a special thanks to everyone who has stopped to have a friendly conversation at a show, or engaged online or with a project. And the artists I’ve met both at shows and online have been without fail incredibly warm and friendly. But that’s a bit different than the daily din and repeated interactions that comes from an office job. Or at least I need to learn to be more proactive in building that into more of a personal community.

To fill the gap, I’ve cultivated (and, yes, had the time to cultivate) a few friendships with some fellow entrepreneurs, as well as built a few relationships with folks that I’ve done volunteer work alongside of or with - thank you to George, Tina, Dawn, … and many more.

This is something I’m still working on, and something that I miss more than I expected, or even considered.

Important disclaimer: do not refer to this drawing for proper or safe table saw technique. And you see why I do woodworking and not, say, painting!

Important disclaimer: do not refer to this drawing for proper or safe table saw technique. And you see why I do woodworking and not, say, painting!

Necessary Lip Service: Food & Healthcare

Yes, of course, I miss the free food from Google. But I’ve lost five pounds, and am cooking a bit more.

I miss the gold-standard healthcare, though I’m now a proud card-carrying Affordable Care Act member. However, the “bronze” level just doesn’t hold a candle to Google’s plan - even the “gold” doesn’t compare. Fortunately, I’m in good health and this isn’t a major pain point. It has, however, changed my behavior a little: I’m perhaps not as willing to go skydiving now, whereas I went three times in the last five while covered by my employer health insurance.

Being a Part of Something Bigger

On less-materialistic considerations, I do miss both the deep insight to technology trends and the connection to much larger scale projects than anything I am undertaking now. My role at Google gave me previews of specific technology and trends one to two years before they were announced by us or partners with any detail, and my team had influence over multi-billion dollar investments; I heard of the responses to major security threats and attacks that, on the outside, get a paragraph of vague description in an industry rag - or perhaps no mention at all.

I’ll confess I have no particular passion for, say, hard drive caching technologies. But I was fascinated by how evolving mass storage technologies can affect, say, how racks of servers, and thus cooling infrastructure, needs to be laid out. Or more generally, how one small piece of a physical system interacts with a much larger system in non-obvious ways.

Being a part - even if just a small part - of building and running a much larger (cutting edge) system was rewarding in a way different from the satisfaction I feel in building and delivering a beautiful product.

This, like the social interaction piece, I’ve attempted to replace: by volunteering with Habitat for Humanity on an ongoing basis for some of their larger projects; by trying to fill a niche in the solar industry space to grow clean energy adoption; by getting involved, albeit briefly, in some local political issues.

But I feel that, unlike everything else I’ve spoken about so far, this point was uniquely met by the group in Google that I was a part of - this is an aspect that may not be easily replicated in any job.

So Why Not Go Back?

That’s a lot of things to miss, some of which can’t be replicated at a sole proprietorship. So why not go back, to Google, or to another company with similar large scope and complexity (i.e.: a solar company)? I won’t say never, but … I don’t miss the horrible commute; the freedom to deeply explore my creativity and create beautiful things; the time to read a good book or book a trip whenever. And I definitely don’t miss the politics and challenging personalities inherent in any job.

Though it’s still work, now, each day I get to set my own goals and explore my own projects. And I’m able to enjoy beginning each day - and perhaps this also helps with the creativity? though probably not with the table saw! - in a relaxing way with my very own home-made Irish coffee.

Keep It Simple Stupid!

David WertheimerComment

Most of us have heard that saying at some point in our lives: Keep It Simple Stupid (KISS). First coined by the US Navy as a design principle in the 1960s, it's something that I need to periodically remind myself.

Sometimes, however, the engineer gets the better of me. You can see that in the incredibly elaborate mechanical and electrical system I built for my version of the sand plotter in comparison to the simple mechanism designed by Bruce Shapiro for his Sisyphus. Though I got some great learnings from attempting to tackle that project, my version has ended up in the scrap heap.

Well, a more recent project has reminded me of this principle yet again, at the cost of a $400 burned-out circuit board, not to mention the development of the over-engineered solution, costing much more in coin and sweat over the weeks I attempted to get it working.

The Problem: Balancing the Garage Lift

I set up my CNC late last year in my workshop; to move it out of the way when not in use, I put it on the Garage Gator lift, which was the only affordable motorized lift I could find. It comes with a 4' x 6' platform, more than enough for my 1000mm X Carve, but unfortunately, it has one major limitation: the platform has only two cable attachment points to the lift mechanism. That means that if the platform isn't perfectly weight balanced from front to back, it will tilt and dump everything on the floor! (AuxxLift and PowerMax have four cable systems, but at the time, I wasn't ready to drop $1000+ on a lift, several times the cost of the GarageGator. In retrospect, that would've been a much better solution!)

I didn't want the CNC platform to list like this as I raised it into the ceiling...

I didn't want the CNC platform to list like this as I raised it into the ceiling...

... given the single point suspension of the lift at the ceiling!

... given the single point suspension of the lift at the ceiling!

So as I lift the CNC into the ceiling, I have to be very careful to make sure the platform is balanced front to back. Sure, I could do this manually... but this could get super tedious if I'm using it every day, so this led me down a tortuous path to automate the process.

Solution # I: Sliding Counterweight

Fortunately, the platform had extra space to the side of the X Carve, so I decided on a simple solution using a heavy counterweight that would be shifted back and forth based on the tilt detected by a pair of mercury switches. This was simple only in idea:

  • Finding the counterweight. Steel or brass would be ideal, but an 6" metal cube, weighing in at about 60 pounds, was surprisingly expensive. So I decided to pour a concrete cube. At about 30% of the density of steel, I poured a 9" cube to get the same weight. But a cube of concrete isn't as smooth as metal, even with the wood form kept on and a plastic slider underneath, so you run into problems...
  • Moving the counterweight. The mechanics were simple: I used a threaded rod that ran through the concrete block, attached to a geared down low speed low voltage motor. But the first motor wasn't nearly strong enough. The second motor, a "Maker Motor", had just enough torque, but drew between three and five amps, which means I had to be careful in ...
  • Powering the movement. 3A at 12V is fairly modest in power supplies, but no mercury switch I could find could handle that, so I had to add a pair of relays. Actually, I would have needed at least one relay anyways to make sure that a delayed opening of a mercury switch (or bad positioning of them) wouldn't lead to a short circuit in reversing the motor direction and current.

Wow that simple idea took a lot of parts and time. But it largely worked... with one major (and critical) flaw that I hadn't considered prior to putting all the pieces together: weight. The Garage Gator has a 200 pound capacity. The X Carve I have is about 110 pounds. The torsion box adds another 40 pounds. With the 60 pound counterweight, another 30 pounds of other stuff attached to the platform, and random projects left on, I'm well over the weight limit. Though I have safety chains to hold the platform in place should a Garage Gator gear fail while the platform is in the air, I don't want to run any risk of the lift dropping everything on the floor as it attempts to pull the platform to the ceiling, or of getting pancaked underneath the platform! Better safe than sorry here...

So, back to the drawing board.

Solution #2: Double-Duty Gantry

Wait! I don't need a separate 60 pound counterweight - the gantry on the X Carve itself can slide back and forth, and since it carries the hefty router as well, this would serve as a perfect counterweight without adding more pounds!

The gantry is that bar outlined in white, that slides back and forth with the router (the yellow thing - it does the actual carving) attached. Circled in red is one motor that moves the gantry; there's an identical one on the opposite end. The "X Controller" is outlined in turquoise - not much of a picture - but we'll return to the electrical insides of this later.

The gantry is that bar outlined in white, that slides back and forth with the router (the yellow thing - it does the actual carving) attached. Circled in red is one motor that moves the gantry; there's an identical one on the opposite end. The "X Controller" is outlined in turquoise - not much of a picture - but we'll return to the electrical insides of this later.

But it does add a lot of electrical complexity (which is why I did not pursue this idea first). That is, the gantry is moved by a pair of stepper motors, which are ordinarily controlled by the circuitry that comes with the X Carve (called the "X Controller"). And I definitely want to make sure I don't damage that circuitry by, perhaps, sending current back into the device when its not expecting it.

So that means there's two problems I have to tackle: first, making sure my counterbalancing system only turns on when the X Controller is off, and second, having those mercury switches activate stepper motors rather than a simple DC motor.

For the first part, I found this nifty little device and routed the X Controller power through it. When attached to a relay, that ensures that the counterbalancing controls are only powered up when the X Controller is turned off.

The second part allowed me to reuse some of the learnings (and parts) I had gained earlier with my abandoned sand plotter project, using an Arduino microcontroller and a pair of stepper motor shields, I could control the two motors.

It worked with a basic test! Or so I thought... but I'll come back to that.

Since I had a fairly large project box (and a multi-voltage power supply), I took advantage of the extra space for some other electrical enhancements I made: extra LED lighting; the power for the laser module; the foundation for a future closed loop speed controller for the router via the Super PID. So that spacious box became quite crowded afterall.

Can you figure out what's going on in here? Yeah. Neither can I. But I'll try to explain...

Can you figure out what's going on in here? Yeah. Neither can I. But I'll try to explain...

Red: two power supplies, one for the 24v of the laser, and one for the 5v &amp; 12v of the steppers, LEDs, and digital circuitry. Blue: the Arduino and stepper motor controller. Green: mercury tilt switches. Yellow: three relays, two to separate the two stepper motors from the X Controller, and one for the laser module. Orange: Dwyer current switch to detect when the X Controller is on. Turquoise: the power input / output, for two independent circuits so that the high power router of the CNC can be separated from the more delicate circuitry, and allowing for future router speed control. Purple: Wow there's a lot going on in here, we should probably have some fans to keep it all cool!

Red: two power supplies, one for the 24v of the laser, and one for the 5v & 12v of the steppers, LEDs, and digital circuitry. Blue: the Arduino and stepper motor controller. Green: mercury tilt switches. Yellow: three relays, two to separate the two stepper motors from the X Controller, and one for the laser module. Orange: Dwyer current switch to detect when the X Controller is on. Turquoise: the power input / output, for two independent circuits so that the high power router of the CNC can be separated from the more delicate circuitry, and allowing for future router speed control. Purple: Wow there's a lot going on in here, we should probably have some fans to keep it all cool!

Looks so much cleaner and actually organized from the outside!

Looks so much cleaner and actually organized from the outside!

The inputs &amp; outputs for the steppers, the main power, and various low voltage supplies.

The inputs & outputs for the steppers, the main power, and various low voltage supplies.

But everything "unit tests", or works when individually tested, so I plug it all in and start using it. And there's two problems.

Those four big chips at the back are the stepper motor drivers for the X Controller, much heftier than those used with my Arduino.

Those four big chips at the back are the stepper motor drivers for the X Controller, much heftier than those used with my Arduino.

First, it actually doesn't work. The stepper motors require a lot of power, especially given the weight of the gantry and the router. The X Controller has a very powerful chip, the Toshiba TB6600, to drive those motors.  You can see the four big vertical chips at the back of this board.

The driver I'm using attached to the Arduino is puny in comparison. So while it does attempt to move the gantry in the correct direction, because that movement is against gravity - that is, if the platform is tilted forward, the circuitry will attempt to move the gantry uphill in the opposite direction until the platform starts leveling out - there just ain't enough power. I try increasing the motor voltage from 12V up to the driver limit of about 15V, but still no go. In fact, the driver starts shutting down due to overheating. Drats.

But it doesn't cause any problems, so I just leave it in place. And a few months go by, until I finally get to a project where I start using the 24V laser engraver that is also powered by wiring in the same project box. I don my goggles, get the fire extinguisher handy, turn on the laser, and start smelling something smoking. Not the smoking of a laser that is burning through the wood - I smell that too - but the smoking of burning electronics.

Still, as I'm unsure, I turn everything off, and then repeat the experiment. And this time, I start seeing smoke coming from the X Controller. Double drats!

After opening up the X Controller, I can see that one of the four high power stepper motor chips has been fried! I don't try to troubleshoot my rats nest of wiring; rather I just disconnect the whole darn thing, and cry. Or more specifically, I reach out to Inventables, the manufacturer of the X Carve, and I explain the fried chip.

Check out the vertical black chip, second from right. See that brownish-black stain on it? That's a burn mark, presumably somehow caused by my separate controller sending power back to this board at the wrong time. Exactly what was the root cause, I never figured out. But I did figure out that this board is now fried.

Check out the vertical black chip, second from right. See that brownish-black stain on it? That's a burn mark, presumably somehow caused by my separate controller sending power back to this board at the wrong time. Exactly what was the root cause, I never figured out. But I did figure out that this board is now fried.

Kudos to them, amazing customer service, they ship out a new circuit board with priority shipping. So a few days later, I'm back up and running, but with a much reduced and simplified wiring setup: an independent regulated power supply for the laser, and nothing else.

But I still have the problem of balancing the gantry...

Solution #3: Biomechanical Feedback System (KISS)

Finally, I've found a solution that works: turn the power to the CNC off. Then manually move - with my hand! - the gantry to the position where the platform is balanced. Voila! It works!

Final solution : If the table tips forward, push the gantry to the back (in the direction of the red arrow). If the table tips backward, push the gantry to the front (in the direction of the blue arrow).

Final solution: If the table tips forward, push the gantry to the back (in the direction of the red arrow). If the table tips backward, push the gantry to the front (in the direction of the blue arrow).

Granted, when I started trying to solve this problem, I thought I'd be raising and lowering the CNC daily, perhaps several times a day, whereas after a few months of use I find I lower the CNC for a project - which may last one day or three weeks - and then only when done with that project, raise it back up. So rather than balancing the platform 300-600 times a year, it'll probably be 20-30.

If I could start over, though, I'd get that more expensive garage lift... or maybe its just time for a larger workshop!

Furniture Rendering Software

David WertheimerComment

I've used a few software modeling and design packages over the years to help with architectural drawing and furniture design, starting first with Claris CAD on a much-earlier Mac in the mid 90s in high school!

Though I considered myself an expert on that, having taken a few semester-long classes on it, and continuing to use it for personal projects in the years just after college, a few computer upgrades, and operating system changes, combined with a multi-year hiatus from woodworking (and the related drawing), meant that I had to start over whenever I needed to draw since then.

I've never spent enough time with any other packages in the intervening years to consider myself even just "proficient", dabbling in AutoCAD, LibreCAD, QCAD, and SketchUp when a need to produce something more precise or complex arose. But when I added the CNC machine to my shop - see more about that here - I knew I needed to learn something that could send commands to that tool.

The XCarve CNC comes with a free subscription to the web software Easel for exactly that purpose, but while Easel is incredibly easy to learn, it's also incredibly limited in it's capabilities. After reading a lot of reviews - and focusing on three key criteria of free, Mac-compatible, and XCarve compatible - I came across Autodesk's Fusion360 software.

I'm still no expert in this software. Indeed, its so powerful it seems like folks might spend years working with it, and still only know one small area in depth. But it's become my go-to tool now not only to drive the CNC, but for rendering commissions.

This isn't a tutorial - I'm far from knowledgeable enough to even consider that, and there seem to be hundreds of great sources for that already. But rather, this is just an opportunity for me to share a few of the different renderings I've done for clients.

Entryway Shelf & Mirror

Though the design wasn't complex enough to require a rendering, as the client considered different woods for the surface, this really helped them finalize the walnut and maple combination.

For far more details on this piece, check out this post.

Oval Mirrors

A commercial client refurbishing a carousel in Irvine needed 24 oval mirror frames, each of which was comprised of 4 pieces end-joined with tenons. While this may have traditionally be cut with a template, I found it much easier to do with the CNC. So here, the drawings were only necessary as a way to control the CNC.

Sun Catcher

Sun Catcher.png

An in-progress addition to my catalog, a pair of these wooden pieces will sandwich nine stained glass tiles. This also gave me opportunity to learn and take advantage of constraint-based modeling, wherein instead of defining a model by the length of each line, the model is defined by relationships between the lines such as "perpendicular" or "equally spaced", so if I want to change the size of one side, or the size of the glass inserts, rather than redrawing the entire piece, I can just update one number and see the entire model update.

Nixie Clock

The body of the long-in-progress Nixie clock I just recently completed was first attempted via manual milling with my drill press; this was the initial impetus for the CNC. This used the CNC in th places: milling out the wooden block; drilling out the control panel; and then engraving the logo and the control panel labels.

Cable Box

A request came in for a decorative box to hide a cable box and media devices and cables, with a built-in shelf and ventilation holes that I designed to double as handles. This was never built.

Cable Box.png

Boathouse Shelf

This oddly-shaped shelf is for a kitchen counter of a boathouse in Emeryville; the rendering helped her understand the final product. I also took advantage of the capability to produce projected dimensioned drawings very quickly from a model; as I updated the model, the projected drawing also automatically updated, making it much easier for me to build the final product.

Screen Shot 2018-04-09 at 5.33.53 PM (2).png

Entryway Tray

The original request to feature a purpleheart stripe led to the rendering at left, which helped refine the design to what I ultimately created at right.

Kitchen Bench & Built-in Storage

This client had a firm idea of what they wanted for the kitchen, but was a bit more nebulous on the wall of bookshelves & desk for the study. Regardless, as both pieces were fairly substantial, a detailed line drawing, and a rendering in white paint helped advance the conversation.

Fusion360 Plug

OK so I'm obviously quite new to the modeling (as opposed to drawing) world: wow, it automatically produces projection drawings for you? This was probably news fifteen years ago! And I'm just barely scratching the surface of the software's capabilities - for instance, I could do a structural analysis of anything I model as well!

Not bad for free, eh? So long as you have under $100k in revenue - or use this for academic purposes - it's free. So check it out, or share your thoughts on what software you know and love!

And... if anyone has software to open those 1990s-era Claris CAD drawings I did way back when, let me know! I'd love to see what crazy (or probably quite mundane) designs I was coming up with back in my teens.

2018 Show Schedule

David WertheimerComment

2017 was a year of learning what shows might work, and which ones I needn't repeat. So I'm super excited for my 2018 show schedule, with the new ones in bold:

  • May 5 & 6: Mountain View a la Carte
  • Jul 14 & 15: Los Altos Arts & Wine Fest
  • Jul 21 & 22: Menlo Park Summerfest
  • Aug 18 & 19: Burlingame on the Avenue
  • Sept 8 & 9: Mountain View Art & Wine
  • Sept 15 & 16: Mill Valley
  • Sep 22 & 23: Oakland-Montclair Village
  • Oct 6 & 7: San Carlos Art & Wine Fest
sfmap-2018.jpg

Dropped from this year are Lafayette, Novato, and Alameda. Also, I'll probably end up at at least one of the monthly Treasure Island, Oakland Jack of All Trades, or Oakland Museum of California events, though none are yet booked.

Come visit!

CNC & Torsion Boxes

David WertheimerComment

I've really enjoyed working with my CNC so far, though I'll confess, I've been doing mostly prototyping - and one giant commission of twenty four oval mirror frames - with no finished products in my catalog yet to show off. But a lot of the time I've been spending with the CNC has been setting it up just right.

As mentioned in an earlier post, many of the next posts will be about the nuances of getting this thing set up, and with the first in the series, I'll talk about "torsion boxes". A torsion box is just a fancy word for a common construction technique where two thin layers of material are applied to either side of a lightweight core.

Flat, Light, & Strong

torsion_box_door.jpg

The most common example that we interact with every day is a "hollow core" door, that is, probably the type of door inside your house. They're super flat, fairly light, and yet very strong. If you were to peel back the thin wooden skin on one side of that door, you'd see a grid of material perpendicular to that skin made of something light and cheap- thin wood, or perhaps even cardboard, depending on the door quality. But they're also used in ships, furniture, some bridges, and many other places as well.

A few months ago, I bid on a kitchen cabinet project that included some 2" thick 15" deep shelves edge mounted on the wall. A 2" thick shelf, if made of solid wood of any variety, would be really heavy and expensive. For instance, a walnut shelf that large would be 0.7 pounds per inch of length, or 25 pounds for a 3 foot section. Mounting three of these on the wall with hidden hardware would be challenging to say the least. Solid wood also expands and contracts with moisture and temperature, making it more challenging to use for large solid wood furniture - see this blog for some more details about that. However, if made with 1/4" veneered MDF (medium density fiberboard) - a very smooth engineered product used as the core within a lot of furniture - the weight would be cut by more than half, to about 12 pounds for that same shelf.

Gaining Extra Height

Now let's return to the world of the X-Carve CNC. I added some extension brackets that allow me to work with much thicker blocks of wood with the machine, up to about 4.5" thick. But the X-Carve z-axis only goes up & down about 3", so that means that for the more common thinner stuff that I'll be cutting and carving, such as a cribbage board or a customized cutting board, the cutting head wouldn't be able to reach the material.

You can see one of the silver brackets giving my machine an extra 2" of height in the lower left

You can see one of the silver brackets giving my machine an extra 2" of height in the lower left

Here's where the torsion box comes in. By adding another 2" layer to the bottom - kind of like a high chair for my CNC - that negates the effect of those brackets, so that I can work with standard-height materials again. But it's critical that the surface be perfectly flat, so that it doesn't introduce any errors into the CNC.

Bonus: Vacuum Clamps

Instant 60 pounds of clamping force

Instant 60 pounds of clamping force

One other great bonus of this setup is that I can now easily use my vacuum clamps. The vacuum pump I purchased is great for veneering, but with a vacuum, you can also easily clamp flat items - like that cribbage board, cutting board, or a sign - if the underlying surface is also flat.

In fact, every square foot of clamping surface exposed to these vacuum clamps produces about 1300 pounds of clamping pressure. The vacuum clamps aren't a square foot - they're closer to 2.5" x 2.5", which produces only about 60 pounds of clamping force, but that's still huge - especially given that they do not mar the surface of what you're clamping, provide complete access to the top of the item, and are nearly instant to insert and remove, with the aid of a foot pedal.

The X-Carve "waste board" - the gridded board you see in some of the pictures - is perfectly flat. But it also has about one hundred holes drilled into it, so that you can use screw clamps. You can see those in that picture above as the green and blue plastic inserts sticking out of the board. They're very useful in their own right, but they limit the use of the vacuum clamps since, unless they are very carefully placed, the vacuum just goes right out the other side of the board, through those holes.

Wrapping It Up

So there ya have it - now you know what a torsion box is, and you could even make your own door if you so desired! But if you'd rather have me make the doors - or anything else for your home or business - look me up! I'd be delighted to explore your project with you.

How to Build a Cabinet in Ten Easy Steps

David Wertheimer1 Comment

I’ve been fortunate to get a number of commissions, both large and small, in the past few months, which has kept me from making a more recent post up, but it has also given me a bit more to write about.

Today, I’ll drill into one of those commissions in detail, share the construction considerations, and show some of the steps along the way.

Interested in discussing a piece? Send me an email or give me a call!

Entryway Shelf & Mirror

The request from the client was for hanging entryway shelf for their recently completed remodel, to fit between the angled walls. After a little more discussion about what woods might look nice together and complement their decor, they decided on walnut and birdseye maple, and for a wall-mounted mirror frame above.

The client provided a template for the top and the desired width. We had to go the template route - rather than me personally taking detailed measurements - as the piece would be installed in a condominium in Florida. After going through a few more detailed questions about design - top surface overhang, depth, etc. - I was able to produce this rendering that the client signed off on.

Rendering.png

Veneer or Solids?

There are two main construction techniques that were possible here: solid wood, or veneer. As touched on in an earlier post, though solid wood has some advantages, for something of this size - especially as it will be installed in a home in Florida - would deteriorate over time if made of solid wood with glued joints. Not to mention finding or joining together boards of that size would be either a lot of money, or time, or both. So that steered me towards a predominantly veneered MDF (medium density fiberboard, an incredibly smooth and stable engineered wood product made of wood fibers glued together under considerable heat and pressure) construction technique for the large top and bottom.

However, the front edges would not be great as veneered: as they would get a bit more abuse from bumps, I decided to use a thin strip, approximately ⅛” thick, of solid walnut as the “edge band”, and for the veneer to cover the top and bottom of that as well so that it would be indistinguishable as an edge band. Much thinner than ⅛” , and it might as well be veneer; much thicker, and you run the risk of “telegraphing”, where that edge band of solid walnut “moves” (expands and shrinks) with the changing temperature and humidity, but with the more stable veneer and MDF glued on the top and bottom, gets stretched.

I also decided to make the three vertical uprights of solid wood, for a few reasons. As they were much smaller, I had neither the challenges of cost of availability, or weather stability, of the top and bottom. And I decided to remove about half of the material on the outer edges of the two sides to make fitting to drywall that might be bowed slightly, much easier. This removal of material would pose problems for veneered MDF, such as significantly reduced strength in comparison to solid walnut, and the fact that you typically need to veneer both sides of a board to prevent stresses from the veneer from warping the board over time but yet veneering such a shaped piece would be a lot more challenging.

The drawer fronts and drawer boxes would also be of solid wood, walnut and poplar, for appearance and durability, and similarly, because as much smaller pieces, they would not have the same cost or stability problems as the top.

Drawer Boxes

Finally, the drawer boxes and slides posed a little bit of a challenge: given the shape of the drawer fronts and overall cabinet, I could do either rectangle drawer boxes with conventional drawer slides and overhanging drawer fronts that would significantly reduce the size of the drawers, or trapezoid drawer boxes that would have to use simpler undermount slides. The conventional side-mounted slides would allow for very high quality soft-close slides, and “push to open” slides, that a lot of clients like, but the client here opted for the trapezoidal larger drawer boxes with these wooden drawer slides.

So there we have the logic and thought process in the construction and material choices. Now let’s get to work!

Construction Steps

The rough step-by-step is below, with a few steps where I learned a bit more via trial and error, or to explain more nuance, covered below. But first, some pictures along the way!

  • Cut the the ⅛” walnut strips, and glue them to the long edges of an MDF panel; sand to make sure the top and bottom of the MDF-and-walnut piece is still perfectly flat
  • Measure & cut the trapezoidal MDF panels for the top and bottom
  • Cut the veneer pieces for the top and bottom

Three of the four pieces were simple trapezoids of walnut veneer, cut about 1/4" larger than the MDF surface, and so very quick to prep. However, the top had the five pieces of veneer joined together to form the principal element of the design, so I spent a lot more time cutting this out precisely. As I cut each piece, I verified that it would fit seamlessly with the previous pieces cut so far, and then used painters tape to temporarily hold the pieces in place.

However, the painters tape would not work in the vacuum press: though it peels off quite easily under ordinary usage, when clamped under 1000# of pressure for a few hours, some of that adhesive transfers to the wood and is very tedious to remove. So once the cutting was complete, I then used veneer tape - very similar to brown kraft paper tape - to keep the set together.

  • Veneer the solid walnut field of the bottom of the top piece and the top of the bottom piece
  • Trim - via a router with a flush-cut trim bit - the edge of that oversized veneer
  • Route out the back edges of the top & bottom pieces so that the back - attached as the last piece - can fit flush inside to give the piece additional stability and strength
  • Cut the three uprights (left, center, and right), and route out the outside edges of the left and right uprights
d Uprights Routed.jpg

This detail - which you can see at right here - came about in discussion with the client after following up with the template in detail. In particular, the angles and some of the lengths written on the template did not perfectly align with the angles and lengths of the template. Which were correct? We decided to follow the template, but in case there were minor deviations - or the drywall bowed out - I would a) route out the sides so that if the cabinet needed to be sanded down to fit, there was much less material to sand, and b) provide 1/4" radius quarter round solid walnut trim pieces for the top to allow for the opposite possible error, that the shelf was too small. Fortunately, the concern ended up being moot: the shelf fit perfectly requiring neither further sanding nor the quarter round.

  • Install the drawer slides on the bottom of the shelf - much easier to do precisely now before the top gets permanently attached
  • Assemble - via glue and screws - the uprights to the top and bottom, making sure the screw heads are below the surface of the MDF
  • Cut and install the drawer slides

  • Use wood filler and sand paper to make those countersunk screw holes disappear; now the “interior” of the shelf looks like solid walnut
  • Veneer the top of the top, and the bottom of the bottom

This was my "oh shit" moment in the assembly. The veneer glue I use has roughly a 20 minute "open time" - that is, I need to be applying the clamping pressure within twenty minutes of mixing the glue or I run the risk of the glue not holding. This is more than enough time for a small piece, still easily manageable for the unassembled top and bottom, but a bit more rushed for the outer surfaces of the assembled piece, both because the piece was heavier and thus harder to maneuver in the vacuum bag, and also because the top had to be placed precisely so the "joints" of the four walnut borders intersected with the corners of the top.

So, I was scrambling a bit, but breathed a sign of relief when I closed the bag and flipped the pump switch at about minute 15. The bag started contracting as expected, I started to clean up the mixing bowl, ... and then...

download-1.jpg

The vacuum bag burst! And while you can think of this as just a giant ziplock bag, they're a bit more expensive: this one cost $300!

The sharp corners of the trapezoid, combined with the thickness of the assembled shelf, popped the bag, as the vacuum press stretched the material across the edge. This isn't a problem for simple panels - like the unassembled trapezoids - because that stretching is only over about 3/4", and the polyurethane bags have more than enough give for that. But they don't have enough give for a 7" thick shelf!

In retrospect I should have put some spacers in the bag, or skipped the bag altogether, but I didn't have time to think through it now or even find the hole: I had about four minutes left of glue open time! Fortunately, I had plywood laying around already cut to about the size of the surface, heavy woodworking cauls handy, and enough bar clamps to clamp down on something that size. Not quite as ideal as a vacuum press, which provides far more even pressure over the entire surface, but - unless I wanted to potentially start over with cutting the outer veneers and lose a day or two sanding down the glue that would dry on the surface, I made do with the equipment I had on-hand.

Fortunately, it indeed worked out pretty well. Now we have a delicate piece of furniture with veneer / finished surfaces on the exterior, which means work has to proceed much more carefully as I can no longer sand out or as easily repair any blemishes that I might introduce as I move the piece around.

  • Trim - via a router with a flush-cut trim bit - the edge of that oversized veneer
  • Make the drawer boxes with poplar & walnut-veneered lauan bottoms
  • Cut and install the drawer slides to the drawer boxes, notching out the bottom rear rail of the drawers
  • Cut and attach the drawer faces to the drawer boxes
  • Cut and install the back
  • Finish with three coats of spar polyurethane
  • Pack, ship, and wait!

The crate alone was about 20 pounds; fortunately, the size and weight of the crated furniture fit just within FedEx's limits, so I was able to drop it off at my local carrier without too much hassle!

OK the title of this post was a little misleading - there were more than ten steps, and while a few of them were easy, most were a bit more involved. Nonetheless, I hope this gives you a better sense of what's involved in designing and delivering a custom piece of furniture, and so when you talk with a craftsman about their trade, there's a lot more that happens behind the scenes in delivering a beautiful finished piece than just a little sawing and gluing!

Other Commissions

Since the beginning of the year, I've done a handful of other commissions, including:

  • A pair of modern replacement drawers for an antique heirloom cabinet
  • A solid walnut shelf for a boat house in Emeryville
  • A set of 24 oval oak mirrors for a carousel refurbishment at the Spectrum Center in southern California
  • An entryway tray featuring purpleheart, walnut, and maple

Is yours next? I'd love to hear about a project you're considering!

Shop Tour: Part IV - Cutting & Carving

David WertheimerComment

Probably the last for a while in new workshop highlights, as - while there's always more or larger equipment to add - my shop is essentially out of space! Every wall has either tools hanging or a large machine pushed up against up; even all the ceiling space is claimed, between wood storage, a platform for my CNC, and air handling equipment!

Finding space to build those large commissions or occasional kitchen cabinet jobs that come in is a battle, so unless, or until, I move to a larger shop, pretty much any major tool that comes in will be only to replace something going out!

CNC Milling and Laser Carver

One of the things I've been eyeing for a while is a CNC carver. However, very few of my current designs would benefit from it, and part of me feels like it's "cheating" to use a machine to do the cutting and carving for you.

However, I was finally won over by the realization that it actually opens up a lot more capabilities, rather than replacing what I currently do "by hand". And even more specifically and immediately, by my need to make a clock "body" from the solid block of wood that I hope to start with for the Nixie clocks I've been working on.

Let me back up first: what is a CNC Mill, often just CNC for short? CNC stands for "computer numerical control" - imagine a wood cutting head that can move left and right, forward and backward, and up & down with incredible precision. That would be a three-axis (x, y, and z) milling CNC. That wood cutting head is typically a router, into which you can place different size and style carving tools. Or if you replace that router with a laser, you have a CNC laser, great for cutting more delicate materials or doing light engraving.

3-axis vs. more axes machines? For the technogeeks among us, the more axes, the more degrees of freedom over which the machine can move to carve your item. 3-axis machines let you cut and carve two dimension objects, as well as what are called "2.5d" - basically, by using a cutting head that always points straight down, you can cut really complex shapes, so long as all the pockets can be reached from straight above. As soon as you want to cut pockets that can only be accessed from the side, or another angle, you need more axes.

A 3-axis machine can also typically be modified so that one of those axis becomes rotational, making it essentially a computer controlled lathe, opening up even more possibilities such as carving 3d faces or columns, but still not quite true 4d or 5d geometries. This is a great article describing all the different axes, or these pictures may help you visualize.

3-axis CNC mill can do the design on left, but cannot reach the "undercuts" in the geometry on the right.

3-axis CNC mill can do the design on left, but cannot reach the "undercuts" in the geometry on the right.

A CNC lathe, converted from a traditional 3-axis XYZ CNC.

A CNC lathe, converted from a traditional 3-axis XYZ CNC.

This wood Transformer can only be done with a true 5-axis CNC; note the angle of the carving tool, which is a 4th axis.

This wood Transformer can only be done with a true 5-axis CNC; note the angle of the carving tool, which is a 4th axis.

A three axis machine typically has X, Y &amp; Z movement, but one of X, Y, or Z can often - with extra hardware - be converted to A, B, or C, giving you a - say - A, X &amp; Z machine to do CNC lathe-like carvings.

A three axis machine typically has X, Y & Z movement, but one of X, Y, or Z can often - with extra hardware - be converted to A, B, or C, giving you a - say - A, X & Z machine to do CNC lathe-like carvings.

A 3-axis CNC can easily cost thousands (or tens or hundreds of thousands) for large commercial or industrial machines. But with the maker movement, consumer grade machines - especially for those willing to do some assembly and configuration themselves - have recently become affordable. So I added an X-Carve 1000mm (about 3 feet square), with a removable Opt Lasers 6w laser, to my shop.

I'm still in the process of setting it up; though the machine itself has been built for nearly a month, I need to finish the torsion box, the automatic ballast for the ceiling lift, and the laser power supply, which I'll detail in future blog entries.

But here it is, in all it's glory! This is mounted on a retractable ceiling lift so it can easily get out of the way. But that lift has only two cables - one in the middle of the left and the right sides, rather than one in each corner - so I also need to build in a balancing mechanism so that the platform doesn't tip too far to the front or back. Also, check out the silver brackets on either side that allow for a higher-than-normal gantry to carve extra-thick surfaces (2-6" deep); this also means I need to insert a perfectly flat and smooth spacer - or torsion box - for when I'm milling normal-depth surfaces (0-4" deep). In future entries, I'll talk about each of these, as well as the laser - see the laser mount on the left of the yellow DeWalt spindle in the middle.

20180204_154251_HDR.jpg

In a future entry, I'll also provide some more detail about my first few milling projects, but here's a little preview of what I plan to carve out first.

Body for Nixie clock, to mill out of a solid walnut and maple

Body for Nixie clock, to mill out of a solid walnut and maple

Miter-Fold Blade

This "miter fold" blade is really nifty, cutting a slotted V-groove in a board but not going all the way through, leaving just a tiny bit of wood remaining so that you can essentially just fold the wood to create a solid joint with a little glue.

While it allows me to make boxes really quickly from just a large flat single piece of wood that both allows for quicker construction and really cool and guaranteed continuity of grain over the joint, my more immediate use of it is to make an even better version of my simple shelves. I'll be trying out a few new designs here that now, which this blade, become much easier to make.

Miter fold blade profile...

Miter fold blade profile...

... and blade output

... and blade output

One of the shelves  that will benefit from the blade for the right angles

One of the shelves that will benefit from the blade for the right angles

The other shelf  that will benefit, ... but I also will be trying a few variations on this shelf which now become much easier with this blade

The other shelf that will benefit, ... but I also will be trying a few variations on this shelf which now become much easier with this blade

Compound Bevel Sliding Saw

Since I have such a nice table saw, I've never considered getting a radial arm saw for my woodworking. But I recently helped a friend with a small remodel that included cutting and installing crown molding, and suffice to say, that is a PITA to cut correctly by hand with nothing but a plastic miter box. Given that I'll be starting in on another remodel for myself soon, I figured I'd give in and get something to help with these construction projects, a compound bevel sliding saw.

While it's been great for those projects, I didn't expect it to be quite as handy in the shop for my wood working. But having had it for a few months now, I can't imagine how I got by without it! My table saw isn't that great for cutting a few feet off a long plank in that it requires me to push a 8 or 12 foot long board, weighing 30 - 80 pounds, through the blade, and it requires me to make sure there's enough clearance around the saw.

But with this new saw, it's always set up to cut across boards, and also much easier as the blade slides, rather than the wood. Plus, with a 12" blade - vs. the 10" I have on my table saw - I can tackle thicker boards and blocks, for instance, easily slicing down the 4" thick glue-up I made for a custom project.

20180204_154237.jpg

Shop Tour: Part III - Furniture

David WertheimerComment

I had thought the shop was full before, what with wood stacked on the floor and all the wall space covered with machines. But creative reuse of space has allowed me to invest in a few new tools to expand my capabilities, which I'll cover in the next two issues.

Since I had the key woodworking tools already (see Part I and Part II), these are more specialized tools used less frequently, but that allow me to create even more unique pieces and furniture. Some of these will get one (or several) posts in the future, delving into both the nitty-gritty of the tool, and some of the pieces I've made with it, but until then, I'll get into some of the motivation for each bit of equipment, and of course, what it is.

Veneering Equipment

While all my small pieces are made with solid hardwoods, occasional larger furniture grade pieces I build are veneered. I'll confess I started as a veneer luddite: "Sure, veneered furniture can be cheaper because you can use crappy interior wood and cover it with a nice sticker, but all real furniture is made with solid wood".

But first: Why Veneer?

My naïveté here was dead wrong on several counts. First, veneer has a long history, dating as far back as the ancient Egyptians, over 5000 years ago (source).

A prototype coffee table base made of multiple pieces of hardware, joined only with glue, cracked by moisture and temperature variation - see more details  here .

A prototype coffee table base made of multiple pieces of hardware, joined only with glue, cracked by moisture and temperature variation - see more details here.

Second, veneered pieces are necessary for many designs. Typically, veneered furniture is built with a more temperature-and-humidity stable underlying base - such as with medium density fiberboard (MDF) - so that it will have a much longer life than similarly constructed hardwood furniture. You can see an entertaining story and pictures of an example of this from someone who started from a similar place of naïveté as myself here.

Or, if you want a thick shelf - some recent kitchen cabinetry I bid on called for a 2" thick shelves - even though solid piece of lumber might be available and may be within the your budget, it may be too heavy to easily wall-mount. A veneered torsion box (i.e.: hollow-core construction; more on these in a future edition) may be a much better way to go.

Sure, well-made tenon-and-mortise construction or dovetail joints will last forever. But if you're not going to the trouble of those, or don't want the style of those, you're left using glue, biscuits and screws. Yet you still need to consider wood movement with a larger piece, so the easiest way is indeed with unattractive but stable MDF, and then by making it look nice (or amazing) with a veneered surface.

Third reason to consider veneers: you can use a far wider range of woods, far more affordably, and get the appearance of far wider boards than are commercially available.

If there's no waste and the boards are perfectly sized, this table would cost about $70 of solid wood in oak (as pictured here), $200 if walnut, $400 if zebrawood or wenge, or $800 if teak. Keep in mind 1) there is waste from board sizes not being perfect matches to the furniture you're building, 2) there's hardware costs, and - most importantly - 3) there's labor and shop costs. Veneers make those more expensive wood finishes possible more affordably, as well as opening up all sorts of unique designs, as well as making the finished piece more stable to environmental changes, which is critical if the joints and construction doesn't allow for wood movement.

If there's no waste and the boards are perfectly sized, this table would cost about $70 of solid wood in oak (as pictured here), $200 if walnut, $400 if zebrawood or wenge, or $800 if teak. Keep in mind 1) there is waste from board sizes not being perfect matches to the furniture you're building, 2) there's hardware costs, and - most importantly - 3) there's labor and shop costs. Veneers make those more expensive wood finishes possible more affordably, as well as opening up all sorts of unique designs, as well as making the finished piece more stable to environmental changes, which is critical if the joints and construction doesn't allow for wood movement.

For some price comparisons, a square foot of 2" thick rough walnut is approximately $19 at my local distributor (or $8 for one square foot of 1"), but wenge or zebrawood is twice as expensive as walnut, and teak is twice again. So a 1" desk similar to what I just made of solid oak for a client would cost - for the wood alone - at least $200 per desk if walnut, at least $800 if teak, albeit only about $70 with oak. But with veneers, almost any wood would be achievable with about $100 or so of raw material (albeit with a lot more labor with veneers).

So if you want to feature more exotic wood grains, the only way to do it affordably is with veneers. This is also where the cheaper (and sometimes not so cheap) manufactured furniture comes in - sometimes that "veneer" may not actually be wood, but rather, its a simulated wood plastic laminate, or even just a cheap sticker. But if it's a real wood veneer, it will still give you warmth and range of color and grain.

Finally, you can do beautiful things with veneer that you can't do with hardwoods, such as this amazing cabinet done by Scott Grove, an award-winning woodworker; this piece was also written about in detail in his book, Advanced Veneering & Alternative Techniques.

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Finally, the Veneer Toys!

With the motivation for veneering clear, let's get into the necessary - or at least very useful - for it I recently added to the shop.

Vacuum pump: As the name implies, this produces a vacuum, but not for cleaning. Rather, it's a stronger (but typically lower volume of air flow) than a vacuum cleaner. A veneer is just a big thin sheet of wood; to attach it to the MDF, you use a thin evenly applied layer of glue. But you need to evenly clamp that veneer to the substrate while it dries.

The vacuum pump enables you to apply even clamping pressure across a large piece. Basically, you put the glued-up veneered panel in a big plastic bag, attach the vacuum pump to the bag, and turn it on. With a vacuum inside the bag, the weight of the entire atmosphere above pushes down on the veneer - you can typically get the equivalent clamping pressure of up to 1800 pounds per square foot. And unlike a giant mechanical press - it works just as well for curved shapes as flat surfaces, so long as you have a big enough big!

The Excel 5 vacuum pump I picked up.

The Excel 5 vacuum pump I picked up.

Wendell Castle's  massive mechanical clamping press. There are hydraulic and other types of automated presses as well, but vacuum is the most common in a small shop.

Wendell Castle's massive mechanical clamping press. There are hydraulic and other types of automated presses as well, but vacuum is the most common in a small shop.

Of course, in addition to the pump, you also need some giant plastic bags that can attach to the pump, open at one side to insert the thing you're clamping. But these are not particularly interesting to look at when not in use, as they're just giant sturdy ziplock bags.

Edge bander: While the vacuum press will allow you to veneer a table top, it isn't that great for the side of a panel; a more specialized tool comes in handy here that allows you to apply an "edge band" of veneer. Basically, you use a heat-activated adhesive on a roll of veneer, and then some tool to apply even heat and enough pressure to bond the veneer.

A larger shop that does a lot of this might have a full-sized floor mounted tool; at the other extreme, many a piece have been finished with your common household iron and lots of care. I added something in a middle, a dedicated handheld tool from Grizzly. It'll still take some practice, adjustment, and care, but I look forward to using it on my first piece early this year.

The handheld edge bander I now have, with a roll of banding. This can apply rolls as wide as 2", which come in just about any wood species (as well as a variety of melamime colors).

The handheld edge bander I now have, with a roll of banding. This can apply rolls as wide as 2", which come in just about any wood species (as well as a variety of melamime colors).

A floor-mounted edge bander far beyond the reach (and needs) of my current shop!

A floor-mounted edge bander far beyond the reach (and needs) of my current shop!

Giant Clamps

The six foot clamps are taller than my dust collector!

The six foot clamps are taller than my dust collector!

I earlier spoke about bar clamps and how critical these are for any shop. But my shop previously maxed out with 24" clamps, with just a pair of 4' clamps. Well, this ain't really any new and exciting technology - sometimes you just need a bigger version of the same thing!

I picked up four 6' clamps to allow me to complete the pair of commissioned solid oak desks. At about 15 pounds each, they're tough to maneuver, but when you need them there's no way around them! The joint on the top is a standard dovetail, but the shelf immediately below the top of the table is joined to the legs via biscuits, and thus needed a lot of force clamping the legs to the shelf while the glue dried.

 

Dovetail Jig

A dovetail is a very common and traditional woodworking joint that gives a wide range of appearances and is incredibly strong. It's best explained with some pictures.

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While these can all be cut by hand - and traditionally, have been! - I'll confess I do not have the patience (nor anywhere close to the skill) to do that. Fortunately, they can be cut quite easily with a router, a specialized jig, and specialized cutting bits for the router. Though there's many dovetail jigs on the market, I opted for a very flexible Leigh jig that allows you to create not only the more traditional dovetail joint, but also some really unique more curvy joints Leigh calls "isoloc" joints.  Look for these isoloc joints to be featured in some coming hardwood clipboards I have in process.

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Examples of the unique "isoloc" joints that accomplish the same joinery effect as a dovetail, but with a more organic form.

Examples of the unique "isoloc" joints that accomplish the same joinery effect as a dovetail, but with a more organic form.

While I've already used the dovetail jig on the table I built above, I neglected to get good photos of the finished product, but you can see the joint on this practice box I built.

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Perfect Valentine's Gift

David Wertheimer2 Comments

Looking for the perfect gift? Check out these novel bulbs in a silky-smooth polished walnut lamp. In early November, I came across these bulbs that folks seemed to love so much that I could hardly keep the lamps in stock!

Roses, birds, sunflowers, love, and peony metal sculpture bulbs with walnut base

Roses, birds, sunflowers, love, and peony metal sculpture bulbs with walnut base

I just finished a batch of the lamp fixtures, and hope you find them just as cool as I did! You can get the lamps - with any of these five bulbs - here.

More Info

These are fluorescent bulbs, filled with argon or neon gas.  The metal sculpture "filament" inside is coated with different phosphors to produce the different colors. When off, that sculpture is just black, or black and white.

They use 3w of power, run at 120v - standard US power - and are rated at 1000 hours. And they're easily replaceable - I'll provide a link to the distributor with the order. Though these bulbs work best on full power, all the fixtures have full range dimmers so that you can later replace with any dimmable bulb as well.

Amazing Installation Technological Art

David Wertheimer2 Comments

My regular readers have probably observed that I am a huge fan of things that combine technology and art in novel ways. This issue will be dedicated to a event my boyfriend and I attended mid-December at Pier 70 in San Francisco, co-hosted by The Midway, Pier 70 Partners, and Marpi, where that sort of thing was on display.

It felt a little like what some of the artistic installations I imagine Burning Man must have, but without the sand, hours-long drive, or the thousands of dollars of investment it would take to attend the event.

I'll confess: between the beverages we imbibed and the music we enjoyed, we didn't have too many (or really, any!) in depth conversations with the artists or creators, but I'll share a few photos and videos, and brief descriptions of what I understand these creations to be, and I welcome anyone's further thoughts on the exhibitions.

Laser and Fog

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This was quite simple in idea, but very well done in execution: a laser illuminating a single "layer" of fog (provided by a nearby fog machine), so that the complex shapes and air currents can be visualized.

Lit-Up VW Bug

There ain't too much more to say about this one. It's a vintage VW Bug. With lots of lights on it. In some sense, not particularly sophisticated, but certainly attention grabbing!

Dancing Avatars

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Have you ever wanted to be rendered as a dancing dinosaur, or as the Rock Monster from Galaxy Quest? Or dance against a psychedelic background that changes every time you swat at an imaginary globe hanging just about your head? A pair of installations enabled exactly this, by combining the Microsoft Kinect sensor with some clever software (and taking advantage of the great DJs in the background, and plenty of alcohol-fueled participants).

Rotating "Screen"

Though the physical implementation was quite clever and far beyond my skill set, in some sense these rotating arms with full color LEDs was not in itself particularly original. Though much larger in size and color palette, I had a toy version of this from RadioShack in the early 90s. However, the artist paired his far more sophisticated version with some pretty amazing software which he custom built, allowing him to start with an image or an abstract geometric pattern, and then morph it gradually in a variety of ways creating a mesmerizing display that looked like a circular TV screen - a screen that might lop off your arm should you run into it!

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Building as Art

The pier itself was an impressive but dilapidated WWII-era corrugated steel building - more history here - worthy itself of being photographed. But one installation took advantage of a projector and custom-built software to highlight the steel trusses and beams supporting the structure, integrating the art and it's location in a novel way. I've added a few exterior shots from the evening as well so you have a sense of the environment.

And One Parting Thought...

Holiday Gift Edition

David Wertheimer2 Comments

OK this is probably a little late to come in with some of these holiday gifts, but I've always thought the best gifts are those that are both really cool and yet at the same time, things you would never get for yourself, these three items deserve a special mention. OK - maybe I might get myself a gift this season, and pick up one of these!

Levitating Lamp: Flyte

Well, I guess it is a desk lamp, so it isn't totally useless. This piqued my interest as a combination of a using electromagnet force to levitate (and spin), and electromagnetic induction to power the lamp without wires, packaged beautifully in something that looks nice enough to go on a coffee table or in a nice office.

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Admittedly, this is by no means a completely unique product - you may have seen cheap versions with the levitating piece for years on Amazon or in the in-flight Sharper Image catalog. However, in my humble opinion, upgrading it from cheap plastic to a wood (veneer) definitely ups its classiness.

Of course, there are similar beautiful designs available for a levitating planter, bonsai tree, "crystal" lamp, and all sorts of similar products. The prices range from $40 for the globe in the picture below, to $350 for the lamp on top. This is definitely something to consider for the person who already "has it all".

Floating Shelf: RockPaperRobot

If your budget is in the $350 range, and you know the recipient is in the market for a small shelf (and the more affordable shelves like this and this that I build aren't in the running!), check out RockPaperRobot, a Brooklyn firm with a floating shelf, and some other really amazing furniture as well.

RockPaperRobot is an engineering and design company specializing in shape-shifting and connected furniture. ... Celebrating the wonder of physics, our invention ethos draws inspiration from nature to create pieces that are as much experiences as they are objects. Our work redefines traditionally static stuff into dynamic platforms that reflect our appreciation for increased functionality, applied technology, and individual style.

Though just about all their pieces are really novel and worth checking out - such as a full-size kitchen table that stores like a piece of art on the wall, for those who suffer compact living in San Francisco or elsewhere - the one that really caught my attention is their floating shelf.

It is enabled by carefully-positioned rare earth magnets that provide the force to repel the cubes, counterbalanced by the steel rope to keep the cubes in place. (Yes, all these pieces I really admire feature embedded rare earth magnets as a core component of their functionality, including the Sisyphus sand plotter of Bruce Shapiro featured earlier).

And while the engineering alone is pretty cool, of course you want to be able to display it in your home. The one that really caught my eye has a beautifully-done continuous grain walnut veneer - but it's also available in black, chrome, and other finishes.

Time in Words: QlockTwo

This one doesn't feature wood or even wood veneer, but is nonetheless a beautiful watch (or wall or nightstand clock) that looks like a mysterious piece of art when not lit up. It tells the time in words ... but rather than try to explain it in words:

If you look closely, you'll see that the text only get it to the nearest five minute interval, but it has some very intuitive ways to narrow that to the minute, and also to represent seconds, as well as the date.

Credit to my brother for introducing (and gifting me with) one, and to a fellow mentor at the iMentor organization where I volunteer who works at Frog Design and introduced me to the other two.

Nixie Clocks, Wall Sculptures, & More!

David Wertheimer2 Comments

As the summer festivals have slowed down and I've gotten some breaks between commissions, I've had time to work on a few new unique designs.

Wall Art

I enjoyed making - and showing off! - the textured wall hanging, but I wanted to do something even bigger that could be a perfect mantlepiece, or perhaps go above a headboard.

Thanks, George, for the photo!

Thanks, George, for the photo!

I had just started sketching a few simple geometric patterns when I visited a remodel-in-progress of a friend in San Francisco's Laurel Heights; though they had yet to refinish the floors, I was blown away by the workmanship in the solid-oak original hexagon-patterned hardwood floor.

Thus, we have this first triptych, highlighting the rich contrast between maple, wenge, and walnut. Cutting and fashioning this into each hexagon gave me newfound respect for the workmen installing that floor, as I presume it was done with far fewer power tools when that house was built over 80 years ago!

And on a similar theme, I built this square triptych, with the same woods.

Check both of them - and the "Lenticular" textured piece as well - in the store here

Table Lamp

I had started the woodworking for a table-top lamp back in early March, but it sat half-finished since due to a lack of knowledge of the compact lighting parts with which to complete it. This is the second time I need to give credit to Konrad Jarausch of Sunlight Inside, who pointed me in the right direction both for the form factor and a few suppliers of high-power low-voltage compact LED lights. (Check out that earlier post about LED lighting here).

I paired that with a large heatsink and satin-finished acrylic tubing to create this light, which can be configured from two to five layers for a desktop lamp 6" to 15" tall. You can see this in the online store here.

Twisty Lamp 5 - b.JPG
Twisty Lamp 5 - d.JPG

Nixie Tube Clock

Several customers have expressed interest in a "Nixie" clock. The first time I was asked, I didn't know what I was, so I started reading up.

Excerpted from Bad Nixie:

The name Nixie is expanded from Numeric Indicator Experimental (NIX); it is a product of the mid 50's to early 90's and is no longer manufactured. Nixie tubes are the predecessor to the light emitting diode (LED). They look like vacuum tubes, but are in fact a form of neon lamp filled with a mixture of Neon gas and a small amount of Mercury or Argon. Inside the tube are ten successive formed wire digits as cathodes, and a wire mesh anode. Each cathode digit and the common anode has a pin at the bottom of the tube. To light a digit you simply apply voltage between the common anode and the digit pin; when energized the digit illuminates with the warm glow of neon.

Though these tubes are no longer made new, there are probably hundreds of thousands of "new old stock" - which despite the apparent contradiction, is not a typo. These are decades-old spare of warehoused inventory that was never used, and in many cases, in the original packaging. The old stock is primarily located in Eastern Europe, though there are a few American supplies as well.

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I've been unable to find a lot of pictures of original hardware using these, though I did come across this calculator - which apparently had a fairly short sales life due to the small time window before the introduction of the much cheaper LED-based display. However, now they show up primarily in artistic and steampunk clocks, or occasionally in a unique one-off pieces like this impressive Sudoku game!

Though I hope this doesn't linger unfinished nearly as long as the lamp I just completed, it may take a while to finish: the circuit boards are from UK; the Nixie tubes just arrived from Ukraine. I just completed the assembly of the first circuit board, though it still needs some troubleshooting. And I'll need to design and machine a (wood, of course) enclosure that has tight tolerances for all the switches and tubes.

Perhaps this is the final motivation to get a CNC, which will also allow me to carve some of those mazes and geometric patterns? Regardless, as I make progress here, I'll share a few updates & photos.

My partially-assembled circuit board with IN-8 tubes

My partially-assembled circuit board with IN-8 tubes