Flush-cutting dowels, corner keys or screw-hole plugs used to frustrate me because my saw’s teeth always left scratches on the project’s surface. Rather than buy a special flush-cutting saw, I made one from a hacksaw blade.
I used my disc sander to grind off the wavy set of the teeth from both sides of the blade. No set, no scratches. Removing the set from both sides of the blade enables me to pull it from right or left. –Bill Wells