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Mike Wilkins
12-21-2020, 12:27 AM
Finished turning a vase from some Pear wood. Did not go below 3/16" thick walls due to some cracks that needed a generous application of epoxy. Attached the Jumbo Jaws to turn the bottom tenon and heard some cracking when tightening the jaws.
Any tips on using these jaws or do I need to find some better wood to turn.
This was a log that was being turned into end grain.

Eugene Dixon
12-21-2020, 9:16 AM
Ahh, the joy of a vacuum chuck!

Mike, Tighten light, turn slow, tape bowl to jaws/chuck, light tool pressure. Or, just mount, don't turn, and start sanding the tenon away with a coarser grit. I've done it both ways.

YMMV

Best,

Thomas Canfield
12-21-2020, 9:43 AM
Using expansion or contraction? Using painters tape and contration less likely to leave marks or crack over expansion. Also you can use a jam piece with pad to bottom inside and live center in tailstock to turn down to small nub. For deeper piece, pack the inside around jam piece with crumpled newspaper to help stiffen the piece and still take light cuts. I have metal shaft from Don Pencil that allows using a 1/4" sanding pad or similar on end and has a face plate with set screw for homemade disks to serve as filler to hold the open end of hollow piece. The crumpled paper works for odd shape pieces. Vacuum chuck will also work but you need a long section. I do have a 2"L extension with through hole for my 1-1/2" drive on Powermatic 3520B and have used it several times to get a longer vacuum chuck. Lots of different ways. Have fun trying different ways SAFELY.

allen thunem
12-28-2020, 7:16 PM
here is my tip sell them
use the procedes set yourself up with a vacuum chuck