Working with the guidance of the excellent Woodworking Basics: Mastering the Essentials of Craftsmanshipby Peter Korn, I set about to learn how to do mortise and tenon joints by hand. I picked up a traditional style mortise chisel a few months ago and this weekend got to use it for the first time.
This traditional style of chisel really earns its keep with this joint. If you try to use a lighter weight chisel, it twists when trying to lever out the waste. Not so with the “pigsticker” style chisels.
I spent Saturday night learning by trial and error. I tried Korn’s advice on drilling out the waste and then cleaning it up with a chisel. But I just kept splitting out the end of the mortise or rounding over the sides when levering out the waste. My tenons were off too. I needed more practice obviously, but I also felt like I was missing something.
I looked up advice on cutting mortises in Robert Wearing’s book, The Essential Woodworker. He didn’t recommend using a drill at all. Instead he worked the mortise in stages. First you pare it shallow to the knife line. Then you start driving the chisel down on one side. Pull the chisel out, flip the chisel around and drive it down and then lever out the waste. This worked beautifully. You then work yourself down to the other side, but you leave some room at the end. For this 1 1/2″ mortise, I left about 1/4″, which was a little short. This space is solely to keep the chisel from rounding down the corner of the mortise when levering out the waste. To finish up that last 1/4″, you simply take smaller bites, and work back the the wall.
I’ll definitely need some more practice, but it was a successful start.