I marked out the angles on the mortise chisel by “feel,” just by sort of looking at all of the pictures I’ve seen and guessing. With two sides cut away, it looked like this:
I cut out these sections with my larger rip saw. It would have taken forever with anything else. Then I used a block plane to smooth around the oval. I nicked the blade of the plane against the chisel bolster doing that. Boo. Grinding that stuff out is always such a pain.
Following the plane, I used a spokeshave to further smooth the oval shape, then, finally, progressive grits of sandpaper on a block to do the final smoothing. This sequence was quick.
A couple of oil/varnish blend applications later, along with the requisite sharpening, it was ready to use. Here it is with its first test mortise-and-tenon joint (upper left, not that stuff to the right):
It’s a lot of fun to use. Best of all, it’s fast.