preventing rub bearing from rotating on shaper.

[jim mills]

Looking for ideas, Sure, Aigner has something, but I was hoping to fabricate something in a pinch and with stuff from the local hardware store.

[Peter Quinn]

I have to ask....why wood you want to do this? I usually keep them from spinning by putting a lot of pressure on my template. If they stop rotating then they turn at spindle speed and burn their way across the wood. Am I missing something ?

[jim mills]

What I want does just the opposite. I want something like a small brake shoe to rest up against the rub bearing to keep it from spinning, while the cutter spins freely. Then when I ease up to the template, the bearing doesn't burn up my template.

Something like this: But I want to run the bearing on the bottom.

http://www.wynmatic.com/stopavator.html

[Joe Calhoon]

We used to have a piece of wood with leather on it that was positioned behind the bearing. I tapped a hole in the cast top to attach. You can tighten it down to put enough pressure on the bearing to keep it from freewheeling when not against the template. The other way around this is to have a ramp on the template to start where the burning is not on the finish part of template. This is not possible on all templates though.
i think this is still around the shop. I will take a picture if I can locate.

[Mel Fulks]

They seem to all break in after a while and stop easily without digging in to the template. Seems to me there would be less wear on bearings while they are spinning.

[jim mills]

As Joe suggests, I was thinking of some sort of "stick" with a piece of rubber or something on the end of it to jamb up against the wheel. problem I am having now is I have a tight inside radius I am shaping. I am a bit squeemish and am creeping up on it delicately. I have 16 pieces to do, and after the second one, my pattern is showing signs of wear. Arg...

[Joe Calhoon]

We used bearings a lot in the past and my experience was that as they got older the spinning was hard to stop and would burn the template. Spraying the top of the bearing with WD 40 seemed to help. Probably not good for the bearing long term but it seemed to work. We had about 5 different bearing sizes that were used frequently and that would keep them going.
I will say that if you do much curve work a adjustable bearing dead collar guide will pay off.
Joe

[Peter Quinn]

How thick is the template, or how high above the table is the cutter? They make those "board buddies" for table saws, which I find useless for the intended application, but the wheels have a one way bearing like the winmatic jig, they are much narrower, you might be able to rig a stick with a slot to hold the board buddy wheel in position and use that to stop the bearing.

[Peter Quinn]

Thinking this over, I don't know if the hardware store will help, but you could get one of these clutch bearings (or one way bearings). http://www.bocabearings.com/bearing-inventory/one-way-bearings/19255/8x22x9-csk8

I'm thinking you wrap it in urethane of some kind, fashion a holder out of two pieces of thin stock with a spacer between just thicker than the bearing, perhaps some kind of aluminum flat stock, you could mimic the Wynmatic system in a low profile version for bottom template work.

[jim mills]

OK, so a trip to the scrap bin, and I am up and running again. Just ripped a piece of scrap to the right width, and used the fence bolts to hold it in place. Makes a huge difference with the bearing not spinning!

I like the suggestions, and will fabricate something so I don't have to remove the hood. Now that I have tried it, I'm not sure the clutch bearing idea is necessary. I can't feel any noticable "drag" against the fixed rub bearing.

Lots of pucker factor involved with hand fed pattern cutting. I have 4 of 16 cuts made, and I am mentally exhausted!
315910

[Larry Edgerton]

I made one for my last shaper that had a foot pedal. I used 1/2 of a brake caliper off of a bicycle, Campy of course, as the shaper was Italian. It would not work on the new shaper so I let it go with the old one. When I get a pattern job I will make a new one. It was mounted to the dedicated hood for pattern work so when using the standard hood it was not in the way.

[jim mills]

As a former cyclist, I love your idea and story Larry.

[Mike Cutler]

I made one for my last shaper that had a foot pedal. I used 1/2 of a brake caliper off of a bicycle, Campy of course, as the shaper was Italian. It would not work on the new shaper so I let it go with the old one. When I get a pattern job I will make a new one. It was mounted to the dedicated hood for pattern work so when using the standard hood it was not in the way.

Hopefully it was an old Record caliper. Chorus just wouldn't do. :D

[Peter Quinn]

I made one for my last shaper that had a foot pedal. I used 1/2 of a brake caliper off of a bicycle, Campy of course, as the shaper was Italian. It would not work on the new shaper so I let it go with the old one. When I get a pattern job I will make a new one. It was mounted to the dedicated hood for pattern work so when using the standard hood it was not in the way.


That is a beautiful solution, turing wheels on in my foggy mind. Thanks.

[Danny Buie]

Another method to solve this is to eliminate the bearing and use a metal ring the same OD as the bearing mounted to the table insert. This will also make for a smoother and more precise cut since any eccentricity of the bearing is eliminated.


Danny Buie

Auburn, AL