Cole Jaws Dent work?

[Raul McCai]

I'm thinking of losing my doughnut system and building some cole style jaws I have a choice:
(1) Get a 17" diameter Aluminum Jig Plate Disc ( cheap at $15.00) and make it from that or
(2) make it from ply

The base will be the 144 mm Jaws I got for my VicMark
The question is: Do metal cole jaws commonly dent the workpiece? The finish turned rim of the piece would be against the jaws and the forces of turning the base may be an issue hammering the rim into the jaws.

The question alone almost causes me to just default to plywood

 

[Dave Delo]

I've marked or dented a piece with too much compression of the rubber bumpers before but not marked the edge that sits on the aluminum face. I use vacuum and jamb chucks more that anything else so the cole jaws are last resort for me, probably because I'm too lazy to change out the jaws all the time.

 

[hockenbery]

Cole jaws are meant for bowls with flat sturdy rims capable of supporting the whole bowl.
I used cole jaws in the early 90s and did not have any rims damaged from resting on the flat aluminum jaws.
I much prefer using a jamb chuck over cole jaws. The jamb chuck is much more versatile ans is useful for cut rim bowls, natural edge bowls, and hollow forms.

You can also mount and turn wooden jaws on the cole jaws that grip the rim like chuck jaws grip a tenon. See the Dale Larson article in the Woodturning Fundamentals september 2915 page 6

 

[Raul McCai]

Woodturning Fundamentals september 2915 page 6

Thanks . I had something like that in mind. I figured not everything would lend itself to the simple rubber stoppers one sees all over the internet, and a variety of wood, shop built, ad hoc structures might do a right fine job for individual pieces.

did not have any rims damaged from resting on the flat aluminum jaws

Thanks. That pretty much answers the question.