And here's a callus and there's a callus..
General mountain dulcimer or music discussions
One way to hasten the development of calluses is to soak your fingertips in vinegar or olive brine or something like that. Old school baseball players used to urinate on their hands to toughen up the skin. If you do that, though, please don't play my dulcimers.
Some people's personalities have similarly marinated in vinegar, which hastens the development of callousness. Certainly no one here at FOTMD, though.
