If you don't do head work often, use a Foredom grinder. Speed control built and uses 1/8 and 1/4 shank bits. It gives you cushion from screwing up a job with better control.Faster learning curve with fewer problems. Dental labs have been using them for years.
I do 100% of my head and intake porting with the higher HP Foredom grinders and the biggest (heavy duty) hand piece. Kinda expensive even used for the guy who isn't going to do this very often. I love mine and will never use anything else again
