In between working on the shop frame, I’ve been slowly working on 2 wainscot chairs. It’s been a while since I have made any of these, (the one above is now in the Hingham Massachusetts public library, so I’m told) – a long hiatus means they are again worth a look. The aspect to cover today is the shape of the front stiles, and the resulting configuration of the side rail’s tenon shoulders.
Wainscot chair’s seats are wider at the front than at the rear, so the side rails are angled. So – do you cut angled mortises? Tenons? Or what?
Some have front stiles with a square cross-section. In cutting the front rails’ tenons, it means nothing. 90-degree shoulders, and away you go. On the side rails – what to do? The ones I’ve studied closely have angled tenon shoulders, but the tenon itself is in line with the rail. This keeps the long fibers intact, making a strong tenon. Requires some geometry to get the angles right on those shoulders, I just scribe the whole chair seat full-scale on either the bench top, some clear wide piece of wood, or any other handy surface. Then take the angles from there with an adjustable bevel.
The real challenge is cutting the mortise at an angle. I’m spoiled by cutting most of my joinery in perfect straight grained wood, in which case mortising is easy. In this case, I have to chop the mortise at an angle, so across the fibers. Like those with ordinary wood. Aggghhh.
Back when I made the DVD with Lie-Nielsen on making these chairs, I made two sample joints. Here’s the square stile version, closed and opened.
One hazard with the square stiles and angled mortises is the chance to bust your mortise out the side face of the stile. I’ve done it, and seen it on old chairs. Another way to do it is to plane the front stile to a weird cr0ss-section, and then your rails have 90-degree shoulders no matter whether they are front rails or side rails. And your mortises are parallel to the face they are struck from. Like this:
Sorry that side rail is not quite in focus, but it’s not worth setting it up again! You get the gist of it, the shoulders on that rail are cut at 90-degrees. It’s a weird piece to plane, two corners are 90-degrees, and the others are not. The chairs I’m making now use this kind of front stile. I promptly forgot that & cut one side rail with angled shoulders! Out of practice, but now I’m getting more…
Here’s a somewhat poor shot from the chair I’m now copying, showing the side rail on our right, and the front rail across the top of the photo. You get an idea of the front stile’s cross-section, and the applied molding shows the general angle too.
At the side-rail-to-rear-stile joint, it’s immaterial. You have to use an angled shoulder there, because the flat front face of the rear stiles is parallel to the flat front face of the front stiles. too confusing? When I make the rear stiles I’ll show some of that geometry .
The DVD on making wainscot chairs is available from Lie-Nielsen, and I have some copies for sale as well. It’s long, but in it I make parts for 2 chairs, showing both these arrangements. https://www.lie-nielsen.com/product/home-education-videos/17th-century-wainscot-chair-with-peter-follansbee?node=4243