Quote Originally Posted by 2e0poz View Post
In most cases just use the maths as a guide and learn how to machine (take it slowly and build up). Experience will come out better than the maths any time
I agree entirely. I did a lot of manual machining on the lathes and Bridgeport milling machines at school before any CNC and I'm sure it's helped a lot as I know what sounds/feels/looks right when cutting metals, and what does not.

A bit of common sense applies here - start a bit below the calculated speed and work up. If the calculation comes up with something unexpected that looks like it wont work then research it further to find out why. The problem is you *can* be too careful as going too slow can break the cutter just as fast as going too fast. The formula's are guidelines, no more.