If you could post some specs of the machine, it would help a TON.
HP of the motor,
maybe even sizes of the steppers, or even a link to the machine.
do you mean a 2mm end mill?
for one, make sure you get CARBIDE for machining in that horrible material on a little mill, I have done it, and its a pain in the butt. I took off .03" per pass, and I forgot what feeds I gave it, maybe 1ipm(this was with a 3/16" end mill too)
yeah, the machine was really small that I did the above on, my mill will be completed soon
About RPMs, youll burn up your bits fast if your not careful. a 2mm HSS end mill should run at the maximum of maybe 3000rpm, carbide end mill could be run up to 12000 or so.
Jon