Jack Guzman from Maine
I'm not an expert but have done plenty of these. There are no set rules. The dimensions I gave are what I would use in the mentioned instance,based on past experience. Smaller pins will work,so will double pins. Drill the hole in the mortised piece,mark it's location on the tenon and then driil the tenon hole slightly closer to the shoulder. This offset is what causes the "draw" part of the drawbore.