Boggs Chairmaking Class in Portland OR

[Deirdre Saoirse Moen]

I'm starting this at T minus two days (Saturday) and will follow through until the last day. I arrived in Portland at 8:30 on Sunday night.

For weeks, I've been working on my shaving horse, abandoning a body in hickory for one in hard maple.

I learned some things about building a Boggs-style shaving horse, some of them during the process of making the horse and some as I pondered some construction details while driving north to Portland OR.

Here are a few of them, in approximate order of discovery:

1) The rear legs are constructed the way they are to make it easy to drill through. However, me being me, I didn't do it that way.

2) If you put a threaded rod through the front leg mount (instead of a dowel) and same with the rear legs, you have a horse that breaks down a lot better, especially if you also put bolts through the bottom treadle bar (instead of gluing). I changed my plans mid-stream on this and think I have a better horse.

3) A sharp hacksaw is a Good Thing. Discovering your hacksaw isn't sharp after all the hardware stores Is Not A Good Thing, especially if you have to leave the next day.

4) If you're using pretty graphics software to lay out your ratchet riser's triangles, make sure you get RIGHT triangles. Especially critical if you've put this off until 2 a.m. of the night before you leave. I didn't figure this out until I gathered the little triangle scraps and saw the perfect hexagon they made in my hand.

5) Despite one's love of hand tools, a band saw, even a little Delta BS100, can be a very useful thing, especially on 8/4 stock.

6) Off by one errors may make your piece the wrong size, but that may still be enough -- in my case, probably THE one piece that wasn't size critical was the one that was 1" too narrow -- the lower jaw. Since this attaches to the aforementioned ratchet riser, well, I'll do them both over when I get home.

7) The purpose of gluing one of the treadle dowels in the center and the other on the ends is to allow the upper jaw to be slightly wider than the body so that the treadle doesn't rub on the body. Fortunately, I figured this out before gluing up, though it did puzzle me for a while (which is why I didn't glue it before).

8) Braces rock. I bought a Stanley 923 10" auger brace at an estate sale a few months back (for the gloatable price of $.50), but hadn't really had a need for the beast. When my hand drill balked at a particular task, the brace took over.

9) Corrollary: auger bits stuck 5" deep on a 6" cut are Very Annoying, especially when the brace is smoking....

10) Spouses can be helpful for unsticking auger bits.

Saturday, I was racing to finish everything, double-checking my list of things. I got everything cut, though not everything is ready -- I still have to tweak the ratchet key a little bit (I believe one hole is slightly off-center, so I have to figure out why the dowel's not going all the way through, though, honestly, it doesn't seem to pose a problem. Yet.) and affix the lower jaw to the riser.

Anyhow, I finally got everything done enough to pack the car, then did a whirlwind of packing. I think I managed to forget my framing square, darn it.

So, last night I left about 10 p.m., arriving in Yreka (a little over halfway) at just before 5 a.m. Naturally, I woke up at 10:30 (when I didn't have to be out of the room until noon, darn it), ate breakfast at Grandma's House (also in Yreka, highly recommended except for the decor), then crossed the border into Oregon. Two nasty crashes meant that the Oregon leg took longer than necessary (and meant I missed the open times of Woodcraft in Eugene, darn it).

Okay, now I'm going down to the car to get the rest of my stuff, and finish up the last couple of details on my shaving horse. It's not finished, but it should be finished enough. Pics later.

[Deirdre Saoirse Moen]

Day 1: And then tragedy struck

Since I was so exhausted I couldn't think Sunday night, I deferred the few remaining tasks until Monday morning. I got up at 6 a.m. and went out to my car for a couple items I'd need.

I had several choices of glue I'd brought with me, but the late hour pretty much doomed me to 5-minute epoxy. While one can use coffee cup lids as a mixing platform for said epoxy, coffee stirrers proved to be a inadequate for thorough application.

I did take pictures of the fully assembled horse, then set off for the class. I finished. Go, me!

I was worried about how the horse would fit in the car with the new assembly, but didn't think about stresses.

Unfortunately, this was fatal: the dowels I'd just epoxied less than an hour before failed. Fortunately, as I said, a coffee stirrer doesn't make the best epoxy applicator.

So I arrive to class on time, but am harried, and unload then repark my car, arriving in at exactly 9 a.m. I notice everyone else has a Boggs-style horse except for one semi-styled based on his and half-styled on a more traditional horse.

Everyone introduces themselves. A bunch of us are from California, though I'm the furthest north, several from Oregon and Washington, one from Nevada, and one guy (Phil) came all the way from South Africa for this class and the Windsor class the following week.

I sit down, fiddle with a piece of my horse, relieved that my glue joints did give with a reasonable amount of force. In one case, the joint was too tight to get significant epoxy in the joint and thus was glue-starved; in the other, there was too much gap and too little glue to fill it. Regardless, I was lucky, because that meant the fix was easy.

Initially, I thought about dowels, then realized I should just use threaded rods as a temporary fix, then re-drill the holes out when I had access to a drill press. Everyone else used either 5/8" or 3/4" dowels, which would have been my first choice (I even have a lot of 3/4" dowels), however, my drill wouldn't drive the 3/4" bit I happened to have, and I didn't want to do all of them with a brace (especially being such a newbie with one), so I stepped the dowels down to the next size I had an appropriate bit for: 3/8".

Needless to say, I was a bit distracted by the morning's failure, but I tried not to let it get to me.

Brian talked about the goals for each day of the class, which I dutifully took down in my notebook, but I left that in the classroom, so this is without notes.

One of the things he did emphasize, though, was that he recommended that we do every step, and not do everything perfectly. As he said, if we were working on it on our own, we'd take more time, but as class time was limited, we should adjust our workmanship downward. Don't make everything perfect. Learn what you can.

Monday's goal in the class was to steam bend all parts, so Brian talked a lot about how wood worked and how steambending works.

We selected our rear leg pieces, then bandsawed off the taper on the front (which starts not far above the rear rungs and goes to the top). We then made the back half "octagonal" (half-octagonal?) with the bandsaw and a vee jig.

Because the piece needed to be fairly smooth to bend well, we then planed down the taper surface to remove the band saw marks. I started out behind (fretting over the shaving horse), so Brian pitched in and planed my other leg flat. Day-um, he's fast with a plane.

Then lunch was delivered and all work stopped. I discovered that I really really needed to be drinking more water, so I tried to make up for my earlier dehydration by drinking nearly a quart.

About this time, the steamer was ready, gurgling away (but not yet fully hot, because it's safer to put the wood in when it's not), and we stacked our legs in (having first put our initials on the bottom of our legs).

After that, Brian talked about the theory of bending and bending forms more, and a lot of people asked questions, some of which I wrote down in my notebook. One I recall was about Shaker oval boxes and why the steam time is so short (typically 15 minutes soaked in hot water rather than steamed). Brian said he wasn't certain, but suspected that the wood for Shaker boxes didn't become fully plasticized the way a steam bend would, rather they got just flexible enough to bend around the form. They didn't need to retain the shape; the drying form and the tacks helped them.

Okay, I'm a heavy person, so one of the things I feared was breaking the wood when using the bending form. Boy was I wrong! Not only didn't I break it, I actually needed a little bit of extra help to get it fully bent. I suspect this problem is more due to my overall lack of arm strength; I simply couldn't bear enough of my weight onto the wood to fully engage it onto the form. Fortunately, there were other people around, but it is something I will have to handle differently and plan for if I'm doing this by myself.

Apparently, people who do a lot of steam bending, Brian included, have a commercial sauna for same. The mfr also sells a lot of them to people who make hockey sticks. Not something I would have expected, eh?

While we were waiting for the slats to heat up, and during a lull when other people were doing other tasks, I asked Gary Rogowski where the nearest hardware store was and decided to take a side trip there so I could pick up the parts for the horse repair and be done with it.

So, side trip to Wink's, which is an awesome, awesome hardware store. It's kind of like an auto parts store -- you ask for the hardware and they find it for you. When I wanted to double-check how large the nuts were (outside diameter), the guy whips out his little gauge to check. I was going to need a hacksaw. I didn't realize the guy had gotten one, so I saw they had a Starrett one hanging up and I selected it.

"Oh, you want the Cadillac," he says.

"I have a fondness for Starrett," I say. That's when he mentions that the gauges they use are also Starretts. I immediately heart them. The other guy up at the counter is being helped with a more complex problem. The woman helping him is suggesting intelligent possibilities for his design problem. Not just a bolt pushed out the door, a whole freakin' service to solve customer's problems. Imagine that.

I go to pay, and the clerk asked if I owned the PT in the lot. I said that I did, and he said that my front passenger tire was low (and it was). So, not just great hardware service, but great human service too.

I get back to class and Brian's just gathering everyone back to talk about drawknives and drawknife safety. Basically, he said, drawknives caused more blood loss, more stitches, and more people going home early than all other tools combined. Keep your drawknife covered. Don't put it down near ANYTHING else -- frequently, the injuries occurred while reaching for something near the drawknife. Obviously, I need a better cover for mine....

Speaking of which, my biggest disappointment today, which will sound silly to some of you. I was secretly hoping that Brian would be bringing some unreleased LN kit, specifically in the form of drawknives and the like. Nope. In fact, he had none at all. Some of us brought stupid little carver's drawknives. One guy had the Barr medium, which Brian thought was way too big. I believe someone else had a Curry, same problem. Boggs pointed out that most drawknives weren't made for chairmaking and were balanced for different applications. Never knew that.

So, by this time, the chair slats were ready, so another round-robin of bending started. Because it's easier, Boggs suggested we bend one side first, then the other, then bend in the middle, as it's much easier to get a complete curve. One poor soul had the misfortune to break three chair slats in a row. In one case, he was bending it only in the middle, but other than that, there wasn't any obvious reason (that I saw) in his technique that would cause failure. Once we'd held the slat to the bending form for 20 seconds, we then put it into a form for drying. Basically, this consisted of a plywood board with two boards battened to it, each cut with a 45 degree edge (bevel to the inside, of course). The battens were 1" closer together than the slats were long. Interestingly, on a previous occasion, I'd calculated the back bending distance at 1.07", so it's good to know that my calculations were pretty close.

Once we finished with the bending, we were done. I was exhausted (too little sleep three days in a row, tired from the agony of defeat.

I went to find a gas station, but got turned around and wound up going south rather than north. Found a little tire store that was happy to put air in my tires. Gratis. I wish I remembered where I was so I could tell you more about how cool they were.

When I got to my hotel, I needed a nap, so I picked up some of the complimentary orange chamomile tea and snuck up to my room.

Now it's dinner time. Tomorrow, I'll go in an hour early and put the rod and bolts on so I can use my shaving horse. Wish me good healing thoughts, please.

Oh, wait, I forgot one thing. I'd been dreading one aspect of this class: the fact that we were also going to use hickory. As it turns out, the hickory rungs were already prepped for us. Boggs used to have students do the rungs themselves, but he said they looked dead by the end of the week, and he figured they weren't learning anything additional by doing the rungs themselves. Go, Brian! We're also using maple instead of the cherry I'd hoped for, but that's cool. This stock is air dried from a tree Brian felled and sawed for best chairmaking yield, which isn't the same as best clear lumber yield.

[Alan DuBoff]

Good read, good luck with the class!

[James Mittlefehldt]

Yes Deidre a very interesting read and we all get to live vicariously in your class with you. Keep up the good work

[Deirdre Saoirse Moen]

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.

[Steve Evans]

Deirdre

Great write up. I got a chance to hear Brian talk at a conference earlier in the year. I got quite the kick from how laid back he was. It sounds like a great class and a lot of fun.

Steve

[James Mittlefehldt]

Can hardly wait for tomorrow but I will be in New Hampshire so will have to catch up when I return Sunday.

One question didn't Boggs have a spokeshave made by Lee Valley for a time, or is this the Lie Nielson the new and improved model?

[Deirdre Saoirse Moen]

He did have a spokeshave made by LV for a time, but wanted to make some changes again, and was also interested in making more kinds of things for chairmakers. (Which they are now doing)

The LN is his next model of design.

[Mike Henderson]

Deirdre, Thanks for the report on the class. It's really enjoyable.

One question - in the picture of the back legs on the forms, how are the leg pieces held in place? It looks like there might be wedges holding the legs in place but if wedges are used, how is the piece put into the form? Seems like the piece the wedge would press on would get in the way of putting the leg into the form.

Or is it like a wooden plane with two pieces on the side for the wedge to ride against?

Mike

[Deirdre Saoirse Moen]

Good question. This was the holding form, which is different than the bending form (which was a bit more extreme). For this form, the top of the leg went into a notch in the plywood (sized so you couldn't put the leg in toe-first due to the top taper). We'd have to drive it home into that notch with a hammer, then bend the leg down onto the form, put a dowel through the form (dowel was 1-1/4" or 1-1/2"), then put an appropriately-sized wedge in to hold it as flush to the form as possible.

There were pieces on both sides of the form.

[Pam Niedermayer]

...
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.
...

Here are the tools I use to clean up and/or out mortises:

http://www.hidatool.com/woodpage/chisel/special.html

Also occasionally I use a strike through chisel for through mortises and for closed mortises to tamp down wood fibers.

Pam

[Deirdre Saoirse Moen]

Thanks Pam, I think I'm going to get at least one of those Very Soon Now. Had I realized we'd be chopping these by hand, I might have thought about that problem more.

[Deirdre Saoirse Moen]

(not all of today's pics are up yet and those up aren't yet sorted)

Day 3: More on bending; mortising; slat theory

For bending, you're looking for straight grain, it doesn't matter if it's flat-sawn, rift-sawn, or quarter-sawn. The face (front) of the bent leg should be flat sawn.

For cherry and walnut, rung precision is critical if you're also using them for rungs. For rungs, Boggs said soft maple is too soft, but hard maple's okay. For one-species chairs, he recommends: oak, hickory, ash, cherry, hard maple. He's never tried exotics for rungs.

Boggs uses Titebond 2 as an end grain sealer on wet wood after cutting off any visible checks. He used to use anchorseal, but it can be VERY slippery on (and is difficult to remove from) concrete floors, and was just too hazardous (because of the slipperiness).

About the sample one of his chairs brought in, in curly hickory: "This chair is a gnarly, difficult wood and I thought it was just perfect for its owner."

Tenons at the end of each seat slat are 22-30 degrees off the chord line between the mortises. Both tenons need to be the same angle. If your seat slat is unevenly bent, try moving the center of the slat to the left or right to adjust the curve (this is one reason why he cuts these oversize -- to givee som play room).

If the curve of the slats are too deep, it pinches the shoulder. If you have to err, err on the side of making the curve too shallow. For a post-and-rung chair, 25 degrees works well. Oh, and to straighten out a slat: push down. That's all, really. Be careful NOT to push down before the chair's assembled.

Cut the slats to different curves so all four tenon angles are the same; otherwise each slat would have different angles.

Boggs trims the back rungs after assembly to get a drop in the rear seat as that is more comfortable than a seat that's straight across.

For the chair back above the seat, 95 - 100 degrees from the seat is typical.

18-19" above the seat is as tall as you can support with slats. Thus, the useful height of a dining chair is 36", but this height is perceived as "not majestic enough" for dining room chairs. When he added a third rung (and 2" overall), Boggs started selling more chairs at a time, because they weren't just settin' chairs (as he calls them), but being used as dining room chairs.

As Phil from South Africa put it: a shorter chair is less formal.

After that, we all got busy chopping our leg mortises. Boggs did (in about 10 minutes, and giving explanations at that) what it took me two hours to accomplish.

2 p.m. "Time for Chapter 14. Put all your weapons away and allow me to be the center of attention." We all put our mortising chisels down.

And then a long lecture that I won't do justice to commenced. I'll do my best, and I'm writing this down as much as for me as for you, because I need to know how to reproduce it when making additional chairs later.

Note before proceeding through numbered steps: Cut and fit your top slat before starting on your bottom slat. If you don't do it that way and make an error in your top slat, you can't easily make it into a bottom slat unless you're making multiple chairs.

So how do you know what angle your seat slats are?

1) Draw a line that's the spacing of the chair rungs. Put the slat on there until it bisects the line at the same length as the rear tenon. Draw the first bit of the inside curve, then measure the angle of that curve at the point at which it meets the line (on each side; they may be different). Note that it's got to be the beginning of the curve, because the angle gets more acute as you get further from the line defining the chord.

1a) Now, measure that angle. For our purposes, it was 25 degrees, so when you see that number in the following instructions, you can substitute your own result. Draw it onto the paper, then also draw a right angle outward. This should be where your legs fit.

2) Next, make a jig. It should hold the legs so that they're splayed at the correct angle (in our case, 25 degrees) so that the leg mortises will come in square to the leg. (If you look at the paper diagram in my flickr photostream, you'll find it easier than if I explain it) Clamp the rear legs in the jig, and then you're ready for the following half-billion steps.

3) Measure inside depth between legs at the bottom front of each mortise. Easiest using a folding extension rule. Don't measure the depth of the mortises at this point, just how far it is between them.

4) Transfer the lengths onto paper.

5) Draw 25 degree angle (facing the starting one) for each slat length.

6) Find a good location on each slat for the curve and mark the slat ends from that line. This is just a starting point for layout.

7) Draw a line through each mark and perpendicular to slat bottom. These aren't final lines, but the bottom corners of the slat will be somewhere along these lines.

8) Mark each mortise with a letter and carefully measure its height and depth. For depth, make sure you get the minimum depth. Since the leg is 1-5/8" wide, in an ideal world, the mortise would be between 1 and 1-1/4", however most of us didn't get that far in the stated time (especially me, I was the slow mortiser).

9) Determine where on the slat you want the top and/or bottom. In part, this will depend on how much "belly" curve you want (Boggs uses 3/8"), and how much curve you want on the top (Silly me, I used 3/8" there, too. Bad me. Tired me.)

10) Mark the starting point on the line where the slat bottom begins or ends. The slat top will depend on the mortise height; there is no shoulder on this mortise (so you've got to be very, very good).

11) With the legs in the jig and a slat centered on marks made in step six, and holding the slat lined up with the bottom of the mortise, have a partner mark each side's bevel angle on the back. Set your bevel gauge to one and check the other. If they're the same, you're golden. If not, re-set your bevel gauge to split the difference between the two angles.

12) Take that bevel gauge and mark from the bottom of each slat upwards the mortise height on each side (I didn't ask what to do about uneven mortises, btw. Chop better.)

13) Then mark the mortise depth on the outside of those lines to form the tenon.

14) Take two spring clamps and a flexible stick (like a dowel) and lay out the top and bottom of the slat profile. The profile for the top should extend to the end of the mortise. For the jig that occurred at the tenon's bottom, it should be removed because it can break off and possibly cause a worse split.

15) Cut the slat using the method of your choice (bow saw, coping saw, band saw, drawknife, alien space ship...). For Boggs, the drawknife is faster than the band saw....

16) Shave off about .002" off the tenon face on each side. Remember that curve? The tenon isn't flat, but the mortise is. Shaving the face will help correct for that. When I say "shave," I mean using a block plane, not a spokeshave. If you're really good with a spokeshave, you certainly could do it this way.

17) Shave down the back until the slat fits into the mortise (and trim the tenon tops and bottoms if required, too.). You fit slats from the back for the simple reason that convex surfaces are easier to plane. Repeat with other tenon.

18) Repeat with other slat.

19) Now they should fit into the rear legs and when the tenons are seated to the depth of the lines drawn in step 12, your rear legs should be as far apart as the rungs want them to be. However, chairs being chairs, they may no longer be at the 25 degree angle you started with. This is fine. From this point on, we're dealing with reality, not theory. As Boggs said when another classmate faced this problem: "According to the chair, the jig is wrong. But you can't trust those chairs," he added with a grin.

[Mike Leigh]

Sounds interesting, where was this class in Portland? East or West of the river?
I get into Pioneer Square and LLoyd Center couple times a week.

[Mike Wenzloff]

Hi Mike--welcome.

Gary Rogowski's school is the Northwest Woodworking Studio
http://www.northwestwoodworking.com/

Just on the East side, not far from Steve Knight's shop.

Take care, Mike