(08-14-2013, 01:33 PM)oldgoaly Wrote: it's the spinning that has me stumped!You may well be 'stumped' but the umpire has given you not out.
The tool bit is spinning and the work piece is spinning both at the same speed, therefore the tool bit is stationary with respect to the work piece. The spinning causes the wobble, it's the wobble (of the tool bit with respect to the work piece) that produces the cutting action.
This video shows how it works - This is on a milling machine the cutter and the work piece are not rotating, but the milling machine spindle is and that cause's the wobble.
DaveH