Friday, February 27, 2015

How I Got Green Woodworking


Green woodworking. It's a term that's batted around quite a bit nowadays. Trouble is, what does it really mean?

Yes, in general the term refers to working wood while its still "green" or wet. But what I never had a clear idea on was the exact reason to work it wet. Maybe I'm thick. Or maybe the literature out there didn't give a clear reason why.

Back when I was cutting my teeth on serious woodworking, I'd read up on every aspect of the craft. Langsner, Alexander, Dunbar, among others. But none of it stuck with me, so I ventured down the road paved with kiln-dried planks and started building stuff. But what about chairs? They were a sort of mystery in my early days. Sure, I could use my skills to build them with kiln dried woods and furniture joints, but as I got more interested in making them, I discovered Galbert and couldn't get images of his work out of my head. Can't make those with planks of wood from the lumberyard. Or could I? When I bought two stick chairs from Chris Schwarz and asked how he got the stock, his answer sort of shocked me. "It's just regular lumber." I knew he'd studied with professional chair makers, so his answer carried some weight.

I decided it was time to take decisive action, decidedly. A week-long, intensive class with Galbert cemented the principles in my mind, and it's affected my woodworking much like the first instrument I built. My woodwork will never be the same.

Here's why you work green wood. It's easy. That's it. There's nothing more to it than that. There's no magic in the moisture. There's no mojo in the medullary. If there's a single reason to build stuff out of green wood is that you can, with a tiny, cheap tool kit, get furniture parts from a tree. And not rustic furniture parts either, but the best furniture parts. You are your own sawmill.

And if you think you have to split green wood because it gets you strong parts, well, that's mostly true, but it's also not entirely accurate. One thing I learned from luthiery is how soundboards are produced. Chair parts need to be strong. But you know what else needs to be incredibly strong? The soundboard on an oud or lute. See, on a typical oud (or again, most any lute) the soundboard is made of spruce that is only about 1/16"-3/32" thick. This isn't oak mind you, its a soft wood. To the soundboard is glued the bridge, to which is tied 11 strings, which when brought to pitch exert over 100 pounds of constant, unrelenting, levering tension through the bridge and the glue-only joint (no pins, tenons, or joinery of any sort) to the soundboard. And if that soundboard has any grain runout, if the grain lines don't flow virtually uninterrupted from the bottom of the sound box to the neck, it will fail. The bridge will find the exiting tubes of lignin and rip a hole in the face in a violent, explosive instant. Bam! And the crowd goes wild. So how are soundboards produced? By sawing. The spruce logs are first split, then each soundboard is sawn from the split face to keep runout to an absolute minimum. The same principle can apply to harvesting chair parts from straight, sawn boards.

Here's the other thing I learned about chair joints from Galbert that took away all of my past frustration. There is no such thing as a dry piece going into a wet piece. This always threw me for a loop. How do you stage parts? How do you keep them "wet?" Do you have to make a chair in a certain amount of time? Do you have to build a whole dining room full of chairs in a week before the legs dry out? The answer is no, because no matter what you do in your shop, a nearly finished chair part can sit in storage for years and still become part of a perfect chair joint. And that's because you're joining a dry part to a super-dry part. And the beauty of all this is, you control when the super-dry part becomes super-dry. It's all in your control. I think of my drying kiln as a shrinking machine. It makes stuff smaller, then it gets bigger when I remove it from the kiln (but not immediately.) That lets me make tenons that can't, under any circumstances, shrink and become loose, unless I put the entire finished chair back in the kiln. I shape the tenon when its in its shrunken state. After it hits glue and lives in the non-kiln environment, it gets bigger. Forever. For me, this was the key that unlocked the understanding of how green woodworking relates to how chairs are joined. Theoretically, you could process enough chair parts for the rest of your life while they are green (again for ease of work) then store them in your shop and build chairs with them at your leisure. When I figured this out, I realized that one could use dry wood, even well-sawn straight-grain lumber and extract chair parts successfully from the planks. Remember Schwarz: "it's just regular lumber." Of course there is a bit more to it than that, but at its core, this is it.

This info was transmitted to me by Pete during our class. But you don't have to take a class with Pete (although I highly recommend it) to get access to his savant-like knowledge of this craft. His new work, Chairmaker's Notebook published by Lost Art Press is now available. I've been reading the PDF for a couple weeks now, and have come to a conclusion. This book isn't about chair making. It's woodworking Kung Fu.

Even if you don't plan to make a chair, this is the #1 book on how a tree is put together, and how best to take it apart.









1 comment:

  1. You nailed it. For some reason green woodworking is perceived as this elusive and nebulous side of woodworking, but it's not. It can all be done with sawn and/or dry wood, albeit straight grained. Riven is simply easier, and produces less waste. Living in the northern Rockies leaves me no alternative to sawn lumber except cottonwood and pine, yet I produce 'green' chairs, etc.

    ReplyDelete