If we assume you are using HSS cutting tools, the maximum speed at which work can be cut depends on:

1. The material being cut - engineers data tables give figures in metres/minute.  (see fig 1 below).

2. The diameter of the workpiece (on the Lathe) or the diameter of the tool (on the Drilling and Milling machines)

3. The number of cutter teeth eg. a drill has two teeth, a plain Lathe tool has one tooth

Put these figures into the calculator below to get an approximate MAXIMUM speed. 

Choose the next speed setting below this on your machine. This figure is no substitute for experience and observation!

If the workpiece squeals or the tool tip gets too hot, STOP, investigate and adapt. 

If you need to use soluble oil coolant, beware of its harmful effects on skin!

​