"mac davis" wrote in message
...
http://groups.msn.com/NovaOwners/geo...nw?albumlist=2

George.. I looked at your album, and don't quite get how the pin chuck
works...

It LOOKS like a chuck screw kind of thing, (Oneway), but a lot easier???


It's from metalworking, really. You can see the roll pin, and there's
decreasing depth opposite the rotation direction. The pin wedges into the
smaller space, trapping the piece and carrying it. This one's from Best
Wood, and it's a humdinger. Had one from my old "Masterchuck" which was
merely a roll pin in a flat area. Bidirectional wedging possible, but as I
don't reverse, this one's the best for me.

As I said in answer, it's a lot of stability, safety and hold for the sake
of a 1" hole. I leave the pillar in and drop a bit into the dried hole,
mounting within fractions of center without half trying.