It was time to make another thirty or so favors for Lori's Waves & Navy Nurses monthly luncheon. I chose to make small ring bowls and turned them from mahogany offcuts and burned a crude fouled anchor in the bottoms. To speed things up I thought to chuck and turn short cylinders without bothering with making tenons. Hollowing the end grain with any pressure at all made them fly out of the chuck even when it was over tightened. I relearned what I had unlearned, so I'll caution a few beginners and remind two lazy oletimers.
George explains it better, but in compression mode although scroll chucks need to close on a tenon radially, just as or more importantly the front of the jaws need to firmly abut the radial foot of a tenon. Clamping, no matter how tightly, a cylinder without a tenon in the the jaws with its end contacting the chuck body is no good, but if you insist on doing it, be sure to wear a catcher's mitt and mask. :)
Turn to Safety, Arch Fortiter