[jamill]

I faced the same dilemma when purchasing my Sherline mill. I grew up using the metric system in school but the imperial system elsewhere. Combine that with the fact that U.S. building products and tape measures are typically imperial somewhat forced the matter to imperial "wins", a decision that always left me a bit uncomfortable.

When it came time to actually order the mill I considered the situation more and came to the conclusion that I didn't really "know" the imperial system and more than the metric system; it was simply more familiar. Further, if necessary I could translate any measurements from one system to the other. That last fact didn't seem like much of an issue: it seemed more like a method to make "doubly" certain of a measurement.

Based on those considerations I ordered the metric mill and have not regretted the decision. Because I didn't have any measuring devices more sophisticated than a tape measure there wasn't a big worry about having already made a big investment in one measuring system.

Instead, to help myself make the transition, I just made sure that I snapped up as many metric or combination metric/imperial measuring tools as necessary from eBay.

Did that mean *not* purchasing nice imperial tools too? Not a bit. I've acquired quite a nice set of "tenths" gages, micrometers, calipers, and the like. It's just that as a novice mill hobbyist I am more interested in perfecting my setup and milling techniques to ensure meeting >repeatable< tolerances than I am in using a particular system. As I develop these skills I start reducing the tolerances to a level appropriate for the task at hand. Whether those tolerances are metric or imperial has become immaterial as long as I can meet them.