Wood Alchemy, or How To Piss Off The Neighbors

Sulfur inlay is a sort of obscure historical process that was only ever heavily used by a generation of two of Amish, a substitute for fancier traditional materials like ivory that weren’t really available to an 18th-century luddite in rural Pennsylvania, but still has some distinct advantages over modern epoxy fillers if you’re a smalltime craftsperson shooting for a more traditional/natural effect and don’t mind everything being some shade of yellow-white. It’s also extremely cheap and simple to get started with, so I’ve been experimenting with it as an option for more elaborate designs I really don’t want to cut marquetry for.

Sulfur powder is commonly available as a fertilizer and chemical reactant, you just melt it to a watery consistency at a hair over 200°F and pour over whatever you want filled, where it’ll rapidly recrystallize and (crucially) expand as it cools, locking it firmly in place. Once cast it’ll last as long as the underlying material does, and if you ventilate well it’s downright eco-friendly compared to most plastics – I wouldn’t sprinkle it on a salad, but you could apparently ingest it all day and not get much more than an upset stomach, and the salad greens would love it. It cleans up much quicker and cleaner than epoxy does – and if you don’t get sawdust and crap in it, which will stain it a blotchy dark color fairly quickly, whatever you scrape off or don’t use can be melted down and reused indefinitely.

Now the downsides: it’s sulfur, the medieval shorthand for what hell smells like. Standards for industrial odors have declined considerably since those days, and I don’t have much of a sense of smell anymore anyway so I don’t much care, but it’s decidedly antisocial, and you’ll be smelling like it for a while afterward. If you manage to light it on fire (which doesn’t take a whole lot) it burns with an invisible flame and gives off some very nasty toxic fumes, which react with water (like the kind your eyes and lungs are covered with) to produce sulfuric acid. To head this off the Amish would apparently bake it slowly outdoors in a sealed clay vessel – we have the advantage of induction burners with no exposed combustion, but you still want to keep an eye on temperature and keep it right around its melting point. And make sure the stuff you’re getting is actually pure sulfur, not some weird fertilizer mix; my first try I used some ebay mystery powder with some kind of absurdly low-combustion-point additive and teargassed the lot of us.

Unfortunately it tends to form bubbles as you pour it out, which I’ve combatted with some success by remelting the surface with a heat gun, but as you can see below it’s still not suitable for large expanses of perfectly even inlay. Will see eventually if a vibration table can fix this, but so far it’s got a strong potential provided you’ve got an outdoor space and local cops don’t care if it looks and smells like you’re cooking meth in your yard.

Paring Knife

A necklace knife made after my wife started getting really into Forged in Fire. Blade came from ebay, as we don’t have a proper smithy around (yet); handle is all roofing nails and sycamore scraps; the sheath is built with a wooden ‘spring’ that latches around the heel of the blade to lock it in place when it’s just hanging there but yank loose when you need it. That part only works on pretty short, lightweight knives but was pretty fun to work out, I’ll probably try some more if I need to stock a fair or anything next year.

Realizing now I forgot to get any pictures between finishing the sheath with a woodburned pattern and selling the thing

Camera

Every now and then I’ll bump into a box of an old project I don’t have the time or energy to finish and get real mad at it, like this disposable 4×5 camera for wet plates I was gonna package up with a portable darkroom. Had mostly beat the light leak problem when it got pushed onto the finish-maybe-someday pile, but not the problem of how to develop in the field without spilling $50 in silver nitrate everywhere, which was kinda counterproductive to the whole cheapo DIY thing.

Prototype

this prototype’s been sitting around my shop for about a year now, intended to eventually be a companion showpiece to some of those inlaid coffee tables posted earlier but I just couldn’t get the back to work right. It didn’t seem like a weak design compared to the doweled backs on the chairs that have been sitting around our, and before us my wife’s grandparents’, kitchen for decades just fine, but when you leaned back something was definitely moving too much for comfort. Examined it while I and others were sitting in it and couldn’t see where the joints were giving, the wood wasn’t bowing, but something was wrong. Shoved a fistful of screws in and near doubled the weight of the thing putting those big chunky reinforcement ribs over every possible weak point, one by one, no dice.

Couple days ago pulled it out of the junk pile and sat in it one more time for good measure – the only part I’d never thought to check was the plank with that big sliding dovetail in the seat, which was flexing so slightly you couldn’t see or feel it except where the movement translated to the top back. Slap a stretcher on the bottom and it’s rock solid. Now to work out a more artful version of that central joint and get rid of those stupid back ribs and we’re in business.

Inlay Design

As designs get more ornate and less strictly mechanical/functional I’m very slowly weaning off just drawing the whole thing layout and engravings and all in QCad. Should help make things less stiff and geometric. And do you have any idea how long it takes to do knotwork or, like, a tree in CAD, with a mouse?

Mouse, Hummingbird, and Apple

First attempt at repousse, a medallion for a garden gate featuring the garden’s most notable inhabitants. Hardware store-grade copper is, as it turns out, much too thin for this kind of work, and as much time was spent on reinforcing and protecting it as making the thing itself, but it’s a neat process I’ll have to develop further.

Tiger Rugboard

Based this design off an antique tibetan tiger rug as an experiment in laser-cut marquetry (didn’t work, made for extremely short cross-grain strips that disintegrated too easily to be worth the hassle) and then for a set of ornate cutting boards after a shop requested them. As I’m not particularly likely to run off more and it’s not really my design to begin with, if you can find a use for it it’s all yours

Going to the log store

Behind a power substation on the edge of town there’s a giant pile where Baltimore dumps every tree that’s been felled in city limits for the last hundred years or so. Show up at the right time and you can strike a deal with the Log Man, who will carve up an entire cherry tree and sell it to you for a couple bucks a board foot.

Wood Dynamics: Moisture

To support the tree that made it wood excels at two things: an extreme strength-to-weight ratio, and absorbing and retaining a truly obnoxious quantity of water. Processing a log fresh off a live (or recently alive) tree can feel a lot more like carving a giant watermelon rind than cutting up the dry lumber you get from the store, the wood fibers rubbery and sodden with up to double their mass in sheer water weight.


You can go right ahead and use it this way, what’s called green wood carving, the simplest and oldest-fashioned way to get from a dead tree to something useful. It’s cheap (free if you live anywhere there’s still forests, the stuff grows on trees and people always wanna get rid of those); much softer and easier to hand-carve; and you don’t have to wait around all year to get your thing. The tradeoff is the wood will deform on you later, and deep cuts using power tools can be a bit fraught, as there are still great stresses in the timber that will relieve themselves as you go. It’s impossible to mass-produce anything this way, and you shouldn’t count on anything terribly complex lasting long, but you can grab a kiridashi or a hatchet or a particularly sharp spoon and get yourself a tool handle that fits your hand more perfectly than any factory-produced item in an afternoon, or find yourself a lathe and start turning out bowls if you have more patience for radial symmetry than I.

I’m not terribly sophisticated with green wood, but if you want to read up more about it, there’s a pretty good book on traditional green woodworking (or just converting a weirdly shaped stick you found into a useful tool) called Woodworking in Estonia that covers everything from carving tools to wagons.

Alternately, given a few months away from soil and rain cut lumber will gradually equalize its moisture content with the surrounding air, shrinking slightly (and unless you take measures to make sure it shrinks evenly, splitting) until sustained humidity or contact with liquid gives it the opportunity to swell up with water again. It’ll slowly breathe over the seasons, expanding and contracting about 1% of its width in a year around the former heart of the tree; but at this point it’s stable enough to do fancy furniture shit to, and kept indoors with allowances made for that movement whatever your make out of it can ride out hundreds of those cycles, many lifetimes.

Either way before or after you’ve finished working on it the wood is going to contract around the former center (pith) of the log, which will probably be torn apart in the process, as shown in the board above. Depending on where it was relative to that and what was going on in that part of the tree the rest is going to try to cup, or twist, or narrow, and will continue to flex back and forth in that direction to a much lesser extent forever. It doesn’t change very much after that initial drying, typically something on the order of 1/8″ per 2′ of width (you can calculate more exactly for your specifics here), but if not allowed to move somehow it will eventually build up a ton of internal stress that’ll relieve itself in some terrible way you did not plan for. Glue joints will fail, unsupported sections will warp, or failing that the wood may just give up and split wherever it’s weakest.

Things that last are generally designed with some wiggle room built in, with grain facing in complementary directions a much as possible and built-in ways to channel the expansion in some non-destructive way. One of my early tables (above) was just butt-joint glued to an apron that ran across the grain and didn’t give the top anywhere to go, and now years later is in the process of pulling itself up and away; these days I use much more stable breadboard ends with a dovetailed slide pinned at the center, to allow the top to get a bit wider or narrower, but not bend vertically or get pulled away from the apron.