Cole Jaw Grippers?

[Bill Alston]

Have any of you made your own grippers for your Cole Jaws? I have a project in mind and the best way I can think of doing it is with my Cole Jaws. This requires a lot more turning though than just removing a foot, and standard rubber grippers won’t, I’m sure, provide enough grip. I’m thinking of making some square aluminium grippers on my mill, possibly with teeth cut into them for better grip. Anyone done or seen anything similar? TIA.

 

[Mike Selser]

Could you mount some wooden blocks to the Cole jaws then turn them to the diameter you want to grip. Can get almost 360° contact that way. Maybe use sandpaper or shelf liner to increase the grip. Have never done this but it seems like it could work. Of course this only works if you are gripping a round object.

 

[Bill Alston]

Thanks for the reply. All good ideas, but I should have mentioned the material will be square/rectangular!
I’ve realised that unless the piece is perfectly square I’ll need some adjustment or packing for two of the sides.

 

[John K Jordan]

For one project the rubber buttons that came with the jaws just barely didn’t fit, so we removed them and short pieces of flexible plastic tubing on the screws. Worked fine.

For an odd shape I might remove the buttons and fasten a plywood disk (cut into quadrants( to the jaws with screws, and make custom buttons to fit.

Another time I mounted plywood disk to a faceplate and made special fasteners to grip the work. Another time I held the work onto a plywood disk with double-sided woodturner’s tape. A disk might be easier than messing with the Cole Jaws.

The tape is quite strong - I know a guy who would turn large bowls with the base held on a faceplate with only the tape. There was no problem holding the heavy blank - took a trick to get it off the faceplate!

JKJ

 

[Bill Alston]

Thanks John. I’ve thought of a few ways for single setups. I’m just wondering if it’s worth making some adjustable Jaws of some type to handle a variety of jobs.

 

[Mike Selser]

Thanks John. I’ve thought of a few ways for single setups. I’m just wondering if it’s worth making some adjustable Jaws of some type to handle a variety of jobs.

How about making the posts as cams that could be rotated to close down on the sides? Make the cams so that the clamping range is equal to the hole spacing on the Cole jaws. Or mount push-pull toggle clamps on the Cole jaws.

 

[John K Jordan]

How about making the posts as cams that could be rotated to close down on the sides?

That sounds like a Longworth Chuck. A google search may be enlightening.

For work holding I have a couple of books with good ideas:

Fred Holder's "A Guide to Work-Holding on the Lathe" (imagine that)
and
Doc Green's "Fixtures and Chucks for Woodturning"
His Chapter 7 is on Cole Jaws, Doughnut Chucks, and Longworth Chuck.

Doc Green's website is also worth a look, IMO:

Articles Index

Doc Green's woodturning tips.

www.docgreenwoodturner.com

Anyone who hasn't browsed Doc's book or website may be missing out on some great practical ideas!

JKJ

 

[john lucas]

I've made wooden grippers with cork on the face to help hold work. I used to have them in several sizes but must have tossed them in one of my moves. I now only have one set.

 

[Mike Selser]

That sounds like a Longworth Chuck. A google search may be enlightening.

I wasn’t thinking about a Longworth chuck at all. I was thinking of attaching cams like these at different spacing in the x and y direction so that a rectangular piece could be clamped.

 

[John K Jordan]

I wasn’t thinking about a Longworth chuck at all. I was thinking of attaching cams like these at different spacing in the x and y direction so that a rectangular piece could be clamped.

Interesting idea. Perhaps make one and try it and report your findings.
Unlike the Cole jaws, seems to me such pivots might need to be well tightened to withstand the rotational forces.
The clamp idea is interesting.
A good vacuum chuck might work well depending on the specific piece.

JKJ

 

[Mike Selser]

Interesting idea. Perhaps make one and try it and report your findings.
Unlike the Cole jaws, seems to me such pivots might need to be well tightened to withstand the rotational forces.
The clamp idea is interesting.
A good vacuum chuck might work well depending on the specific piece.

JKJ

Too many things on my plate right now to try it out. Besides, I doubt I would ever have any use for it. If I did have one I would tighten the cams down well after setting them and probably add a dab of hot melt glue to keep them from loosening.

 

[Tom Gall]

@Bill Alston What size pieces are we talking about? Are "clamping/holding" marks/dents a problem?
For smaller pieces maybe you could just remove two jaws on a scroll chuck to clamp the piece. If the dents (corners of the jaws) are a problem just add some thin strips of wood.
For larger pieces you could bolt 2 (or 4) straight edge pieces of wood (ie. 1x2" or any size) into the holes of the Cole jaws. Other options available if you want to get fancy. This also gives you the possibility for doing some multi-center work or designs.

 

[Bill Alston]

I’m guessing about 6” x 4”, a couple of inches thick. I can remove shallow dents, just nothing too deep.

 

[hockenbery]

This is a photo of what @Tom Gall was suggesting. This is a 2” wide piece held off center.
150mm jaws should hold a 4” wide piece- check this

 

[Bill Alston]

I decided to make some “grippers” and on the first test they worked well. Obviously Cole Jaws are only designed for light cuts at a maximum speed of 600 RPM so I took it easy. They seemed to work well though. The original buttons supplied with the Jaws are at the bottom.

 

[Bob Vaughan]

Wood jaws work just fine even if the pieces aren't exactly square. I had to do a bunch of rosettes (275) for a job and the squares were supplied by others. I realized they weren't exactly square, some worse than others, but I forged ahead with no problems.

 

[Bill Alston]

Yes, I’ve used wood Jaws as well. I wanted something more adjustable hence the use of the Cole Jaws and grippers.

I made a drilling jig so that I can easily make and fit wood jaws directly to my chuck if needed.

 

[John K Jordan]

For those who haven’t seen them, Nova sells a set of four “soft” jaws. These fasten to the chuck with the same screws but can be easily cut, turned or otherwise shaped to hold a variety of things. I have some but haven’t had the need to use them yet.

https://www.rockler.com/nova-soft-jaw-set

JKJ

 

[Bill Alston]

Record Power and Robert Sorby sell those as well.