Soz if i'm butting in, just wondering if you are asking because you are thinking of getting a chuck.



In my experience of both independent and scroll chucks would be that its not a wise move to turn air with an independent chuck, is you do a safety helmet an body armor would be advised as a couple of pounds of timber fair shifts when it zings out of the lathe if the tool catches, it almost impossible to get a good solid hold on the piece on independent wood chucks especially if its irregular, they seriously need the work piece supported by the tail stock.



I have a scroll chuck now that is ultra safe and they jaws are dovetailed so they get superb grip of the work pieces, I almost lost a finger to my evil independent chuck when polishing a work piece the jaws are so evil its unreal, I now have a Record Nova chuck and the worst it has done has been slightly scuffed knuckle.



The accident happened when i was polishing and the pad snagged on some tacky wax due to the pressure i was putting on it and the friction jerked the pad in and my finger into the chuck, it happens fast, i reckon the jaws hit me about 50 times before I go my hand away.



When I got the scroll chuck I purposely brushed my thumb lightly on the chuck at 2000 rpm which I highly recommend that no one tries but i can say that it was just a tickle and didn't mark the skin at all.