Originally Posted by
David Eisenhauer
Sounds like these may be your first or at least "firster" mortises and , if so, yes it will get better as you gain experience. In my opinion, the Paul Sellers demo is one very definite way to chop them with good results. Work bench frame mortises are usually large and deep, so the joint will be solid if some small area of the entire mortise is slightly out of plumb due to minor undercutting. I run a small square along the side and end walls of the mortise to check for any "bulges" that will prevent the tennon from sliding in and tend to skip using a square guide to hold my chisel against because I don't have too much trouble ending up plumb. Certainly a wider chisel helps create a more consistent sidewall, but the 1/2" - 12mm size chisel is probably my most used paring chisel. If the wood is hard, a 35* micro bevel may be better, but that is for you to decide. If the $ is available, maybe order a wider chisel for use here and to add to the collection. Also, I don't tend to pound the chisel for maximum penetration when chopping, but just bop it a couple of whacks to take what the chisel gives me. That tends to keep my chisel better in square than when I try to go for deeper penetration by pounding harder.