"Initially I was going to use a old fashion boring machine. Tried on at the Heartwood school...my arthitus will have no part of climbing up on the timber to sit on the machine...much less a shoulder with an old injury that really didn't take well to cranking the machine."

With this in mind, using a standard drill may not work for you either. The torque delivered by an 1 1/2 drill bit can be significant.

From memory, I remember seeing a lot a single flute, double spur bits in England. It is my experience that Forstner bits clog and bind at mortise depths.

Bob