Here and there I take some time to work on the “board chair” I’m making. I struggle with what to call it. This version has a 3-board back. But for now, I’ll stick with the German “brettstuhl” but recognize that it’s not a very good term for it.
Once I got the uprights fitting into the mortises, I then trimmed the extra length at the back end of the battens/cleats. Maybe you can see in that photo above that the upper tenons have already been drawbored – turns out this is not ideal. Small discrepancies in how those two uprights relate to each other means I need to adjust their shoulders for the crest to come down tight on both at once. So I made a note for next time – leave that drawboring til after fitting the upright’s lower wedges. (for now, I plugged the holes in the tenons and will re-bore them after adjusting the fit. Another learning-experience-chair.)
Once I had those uprights fitting in their seat mortises the way I liked them, I marked the baseline of the wedge-mortises. This wedged-tenon is one place where I do things differently from other brettstuhls I know about.
I first heard of these chairs from a Drew Langsner article in Fine Woodworking in the early 1980s. That chair, made by Drew’s mentor Ruedi Kohler in Switzerland, used wedges driven across the through tenons.
Most of the antique chairs I’ve seen pictures of use tapered pins instead of wedges. And they run from the back toward the front. I decided I like the wedges vs the pins but I like the fore-and-aft direction better. It does have a drawback – you have to miss the legs. (the picture below is from Chris Schwarz – he’s been to places where these chairs come from. I haven’t.)
I bore a couple of holes, then clean out between them to make these mortises. They’re too short to chop in the usual way. Laying them out looks weird because of the angle where the uprights meet the seat. And you have to be sure the mortise extends above the baseline so the wedge will bear on the cleat.
Now I’ll trim the length of these wedges, adjust the way the crest sits. Then bore for the legs.
I made the tapered legs from riven ash. Turned the tenons oversized, then air-dried them for a while. Last week, I moved them to my 4-wheeled kiln to dry the tenons further before turning them to final dimensions. These days I try not to go anywhere, but at least I get some use out of this car.