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Nova Cole Jaws

L

LoneStarKayaker

Joined
Jan 25, 2006
Messages
7
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Location
Iowa
Is there some tip to do when your turned item ( mine was a bowl) will not fit tightly in the Cole Jaws. I moved the screws and buttons into different holes but could not achieve a tight fit. Has anyone ever replaced the original buttons with smaller diameter ones?
Barbara
 
Try grinding/sanding a flat spot on each button. Use a hole that was too tight and maybe they will then fit
 
cole jaws

Have you tried holding the bowl with the stops inside the bowl rim rather than outside?

I have often found that when a bowl won't hold on the outer rim moving to the inner rim does the job. You can also bring up the tailstock just to lightly hold it...although I suppose this defeats the purpose of having cole jaws to some degree.

I have also know turners to make shaped wooden stops to screw onto the plates. I think it would need to be a very special piece for me to go to this trouble though. The beauty of cole jaws, for me, has always been the "quick fix" aspect of using them.

Andy
 
Make your buttons bigger by pressing small rings of automotive heater hose over them. I've never had a lot of luck holding from the inside of things. If forced into that option by the design of the rim, I find myself returning to the tapered plywood circles with some help from hot glue. Of course, the real answer is to plan ahead and design for holding, but how many of us would actually do that?

Fess up, how many of us actually know where those go/no-go pieces of plywood we cut in a flurry of efficiency to keep our tenons or mortises in the range of our jaws really are?
 
One thing I have done in the past is to get longer screws and then put small washers under the buttons to raise them off the surface of the cole jaw. Just an extra 1/4 " can help.

More recently I've become more proficient turning off the final tenon and nub by turning between centers. But there are pieces where that is not possible.
 
One quick fix is to mount the flat right angle corner brackets on the cole jaws and cover them with plastic tubing. I stopped using cole jaws for bowls a long long time ago but these angle braces where part of my standard set up for a while.

I much prefer chucking bowls against a rounded block of wood (sort of bowl shaped) with a pad and the tail stock. This method prevents damage to the rim, is so quick to set up, and it is so much more positive in holding the bowl for turning the bottom than cole jaws.

you will have a small nub left between the tailstock center and the bowl. this needs to be taken off with chisel. With practice you can take this nub down to less than 1/4 inch on the lathe. witha standard face grain bowl this nub is very weak and too much bevel pressure make break it.

When you reach the advanced status you can cut the nub off on the lathe.
I learned this from David Ellsworth. turn the nub as thin as your "comfort zone" allows. hhold a carving gouge on the tool rest against the nub. Then in rapid sequence turn off the lathe and give a little puch on the gouge. this will cut the nub free and the bowl stops turning and the bevel of the gouge hold the bowl in place.

happy turning,
Al
 
Holding a piece on the cole jaws

When I use the cole jaws I tighten the rubber nubs and the chuck only hand tight. I have found that tighter puts too much stress on the workpiece and it can spring free very easily. I treat the rubber nubs more as a stop to make sure the workpiece stays in the center while working the bottoms.

To make sure that the piece doesn't eject itself out of the jaws I use "flat twine". This is the stuff made from a plastic wrap type material that you can buy in an office supply store or packing store. I take the flat twine and wrap the bowl around its circumference alternating in and out of the cole jaw metal plates.

Since I have started using this technique I haven't had a bowl come catastrophically free. They can flex and wiggle off the cole jaw plates, but the flat twine keeps it from dancing across the floor.

I have also found that putting a cloth between the workpiece and the metal plate helps keep the piece from coming free. It also has the effect of preventing the workpiece from getting scratched by the metal plates, or acquiring black marks from the rubber nubs.

Jeff
 
I use the Vicmarc bowl jaw rubbers on my cole jaws as the give a far superior grip on the bowl.
They are tapered from top to bottom and had 4 different radia. They have 2 concave sides and 2 convex sides for holding internally and externally.
because of the extra grip you are able to run at a bit higher speed and get a cleaner cut.
 
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