Originally Posted by Geof  Not only unskilled, sometimes very skilled; the key hasn't been present in my original manual mill for about twenty years and it works fine. As both littlerob and DC say it is only there to stop the collet turning while you tighten the drawbolt. |
Spinning a Collet isn't as risky. With or without a key, I've seen the results of fly cutters and shell mills spin and neither ends pretty when conflicting with a solid object. When it does occur, the only difference between skilled and unskilled operators is; one knows how to cover it up and the other can just play dumb not knowing what all happened or why!
DC