All the legs featured in “The Anarchist’s Design Book” are octagonal or square in section – this makes them easy to make without a lathe. For this chair design, I decided to turn the legs but make the shape simple enough that you could shave them if, again, you are lathe-less in Louisiana.
This shape of leg is a modernized bamboo turning. The top section of the leg tapers and flows into the leg’s tapered tenon. The taper begins 6-1/2″ from the top of the leg and tapers from 1-1/2″ to 5/8″ at the top of the tenon. The bottom section of the leg tapers to 1″ at the floor.
This profile looks nice with the 12.8° taper I use on my tenons. However, if you use a different angle, I’m going to show you how I laid out the leg so you can design it to suit your tools.
First I made the leg blanks into 1-1/2″ x 1-1/2″ x 19″ octagons. I chucked them in the lathe and turned the leg to a straight cylinder (note that after you get the leg dimensions figured out you can skip this step to save time).
Then I marked the length of my tenon (3″) on the leg and turned the tenon very slightly oversized. The tenon starts as 1-1/16″ in diameter and tapers to 5/8″ at the top.
With the taper roughed in I took a straightedge and held it up to the taper and eyeballed where this taper would end at the full diameter of the leg. This guess is about 6-1/2″ from the top. I could have drawn it out in CAD, but I like wood better than pixels.
I marked the cylinder at 6-1/2″ from the top of the leg and then turned the remainder of the top taper to that point. Note that I turned a small groove where the tenon began. This is an important mark when you shave the tenon to its final size.
The rest is easy. I turned the bottom taper from the 6-1/2″ line down to the bottom of the leg. The bottom of the leg is 1″ in diameter. In the photo above I’m looking for humps with a straightedge.
Then I removed the leg from the lathe and used my tapered tenon cutter to shave the tenon to the perfect shape and size. It took only a few turns to do. When I shaved the legs in the tenon cutter I stopped cutting right at the groove I turned in the leg.
Then I sanded the legs (avoiding the tenons) with #180-grit sandpaper and got ready to leg up the chair. That’s tomorrow’s entry.
— Christopher Schwarz