If you use a tenon cutter on the sticks (or spindles) of a chair, it can be a challenge to cut the tenon so it is perfectly centered on the stick and inline with the axis of the stick. This can be a problem no matter how you drive the tenon cutter – with a brace or with a drill.
This short video shows how I teach students to cut tenons. If you take these steps, your tenons will start to improve immediately. Practice will get you the rest of the way.
Note that there is a way to get perfect tenons every time with a tenon cutter. It involves a lathe and a jig. It’s ideal for making 200 tenons at a time. I’ll show that process some other day.
— Christopher Schwarz
P.S. Shameless plug: This tip is straight from the pages of “The Stick Chair Book.” There are lots of little tricks like this in the book.