? what is to define, the 2cd and 3rd cannot Thread (like on a lathe) only spindle 1 in mach is hooked into the threading algorithm
The 2cd and 3rd, where for:
on lathes: if you want to run a "Live Tool" in your ATC, and if you want to run a Drop spindle to machine the other end of the piece (that does not need threading), OR, if you want to run a Router or other machine that you would like independant analog spindle speed control on.
scott