Deirdre Saoirse Moen

Sounds Like Weird

Brian Boggs Chairmaking Class, Day 2

14 August 2006

Day 1 recap additions:

Brian said that he started his first shop for $50. Soon after that, he was laid off, and he never did bother getting another job, because he was soon making money doing woodworking.

He also gave a rule of thumb (though he noted it worked mostly for domestic hardwood) that below 20-25% moisture content, for each 2% loss in moisture content, you lose about 1% of dimension.

When making a chair, ideally, the growth rings of the legs should be aimed around the chair pretty much like they are on a tree. For rungs, the medullary rays should be vertical and growth rings horizontal because of how seasonal expansion occurs.

One guy asked about why the form went on the outside of the curve on a steam bend. Honestly, it never occurred to me to ask, but lest it save someone else from the same issue, here’s the reason: because if you’re starting a bend on a concave curve, you’re only able to bend at the very ends of the piece, which is not actually where you need the bend. If you start on a convex piece, you’ll bend from the part that needs bending.

I also never quite got why sometimes straps are used for steambending, except for large or complex bends where they are required. Basically, wood compresses better than it expands; if you put blocks on the end and a strap around the bend, you’re compressing the front rather than expanding it, so this would lead to fewer bending failures.

Long, thin pieces may need side support for a bend, or a wraparound support like tape.

Day 2: Recovery from Tragedy

I got in early to fix my horse and hey, it worked! I think I learned more from fixing my mistake.

We started with our lecture about sharpening, and Brian got into the various similarities and differences between how drawknives, spokeshaves, and planes cut. He was trying to describe a bench plane without having one, so I offered up the LN 5-1/2. He then started talking about the camber on some blades, and so I showed the Knight scrub plane I also brought. Several people looked at it. Brian asked who made it and I told him, then he said, “Oh, he made those too,” pointing to a shelf with several Knight planes at the front of the class. Guess I’ll try those out before I go home. 🙂

Part of the lecture about sharpness and cutting angle: You can prevent tearing (with a drawknife) by taking a light enough cut. The thinner the chip, the less pressure it’ll take. The lighter the cut, the smoother the surface (of course, this is pretty much true for any tool, powered or not). You want the lowest angle that’s comfortable for your work and stays sharp as long as possible. For finish work, you want a higher angle. The harder the wood, the higher angle required. The higher the angle, the more it’ll wear you out (like a york pitch plane, just harder to push).

Skewing a drawknife lowers the effective angle of cut and also increases the length of sole supporting the work.

In discussing sharpening, there was a funny moment. Brian said, “Some people use glass glued down to sandpaper,” then chuckled because he’d said it backwards.

One of my classmates quipped, “Which side up?”

Boggs quipped back, “Depends on how long you want to take.” I love quick wit.

Later, as he was having issues with a drawing on the blackboard, someone asked if a whiteboard would be better. Brian said, “No matter what you give me to work with, I’m going to gripe about it.”

Another classmate this time, “You need a better back bevel on your marker.” (Everyone busted up at this one, because we’d had a long talk about microbevels and back bevels)

One of Brian’s rules about skewing drawknives and spokeshaves: “Every time I can skew a tool, I will.” He also pointed out that beginners tended to use just one part of a drawknife or spokeshave, and that led to uneven wear.

We got some practice then shaping the front legs in, and I found my hand cramping a lot with the drawknife. The handles were uncomfortable, but I think it was just my unfamiliarity with the tool that caused most of the problems.

Spokeshaves get darn hot during use, which surprised me. Boggs says that his sometimes get too hot to hold, which is one reason he’s got so many. How many? His shaving horse is within reach of a wall where he’s got two rows of a bunch of spokeshaves, including four of the LN flat ones (one set up as a scraper, plus three different setups for depth-of-cut), two round-bottom ones (one set up as a scraper). They each have different handles so he can tell them apart. In addition to these, he’s got a number of vintage shaves.

Boggs then went to demonstrate some point, and managed to knock over the shaving horse while trying to get on it. “You’d think I’d do better than that, coming from horse country and all.” He gave a good demo, and after he’d flipped his spokeshave in the air a few times, someone asked him if he did that with drawknives too. This got a good chuckle out of the class. Seriously, though, one of the things he worked on with the LN Boggs shave was to get good balance for being able to flip it, as well as ability to use it one-handed. He also talked about his frustration with traditional adjusters and why his isn’t set up the same way.

After lunch, we went on to practicing mortises for the next day. I’ve only ever chopped a few, actually, because my hand tools class teacher prepped them for us using a router. Someone asked why we weren’t using a machine (e.g. a hollow-chisel mortiser), and Boggs pointed out that they really weren’t terribly suitable for round work.

When sharpening, hold the mortise chisel’s handle weight with your pinky so the weight of the handle doesn’t skew the chisel.

For a mortise chisel, if the edge isn’t square to the sides, the chisel may lean to one side or the other in a cut, causing the mortise to be out of square.

One of the primary rules of mortise chopping: don’t pry your chips loose, only pry your loose chips. It’s probably easier to clear out chips with a smaller chisel.

Even though Boggs has done many mortises, before he does a real one in a chair, he always does a practice one. At one point, he was the one chopping mortises and was doing as many as 90 in a single day.

After our Fun With Mortises, we got all our back legs out of the solar kilns and pulled them out of the forms. I found that mine were well and truly lodged in, so I used a smaller dowel and a dead blow hammer to get them out.

Some of the guys got a lot of springback, but my legs had nearly none. The poor guy who’d bent his leg the wrong way the first time, well, that leg failed. He was really depressed about the split, and Brian said, “It’s only wood deep.” Heh.

In that case, since it was the back that was split, Brian’s solution was to taper not only the front of the rear chair legs, but also the back, removing the split. He got on the shaving horse and fixed the leg.

For the rest of us, we had to check to make sure that our legs weren’t still overbent. For correcting the curve, we just put a couple of blocks on the end of a bench and unbent it manually. Took most of my weight to do that (and a few tries, too). Boggs wanted to make sure that our legs were evenly bent, which is more important than how bent they were. I didn’t get to see what the legs looked like for the guys who’d had a lot of springback.

I finally got comfortable with my drawknife, at least somewhat. The hands started cramping less frequently. I worried about the way I held it, because it seemed to want thumb pressure behind the cutting edge. Sure enough, when I went over a bump, the work caught on the right side and my left thumb got a small cut. I patched it with cyanoacrylate glue and went on, though I realized I was probably not awake enough to continue working with a drawknife. 🙂

Oh, almost forgot. Pictures can be found here.


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