A 3mm dia endmill at 50k, would not be a problem at all for a ball in some cases. For a light finishing cut, taking say .003 for a finish pass, that would give you a working diameter of about .037, 50k rpm's would be less than 500 sfpm. Not an issue for carbide. I have run finishing passes on hardened cores and cavities at over 1000 sfpm without issues. Of course this is an example with a ball endmill, if your on the full diameter of the tool then your up to over 1500sfpm. That might be pushing it on hard material, mild steel you could get away with it. This would be with a premium endmill of course, no cheap generic tool. |