Shaper rub collar bearing....

[Dave Winters]

So, I'm using a bottom rub collar bearing with my shaper. The bearing rubs on a jig made of Baltic Birch ply and the cutterhead is above it. But it keeps spinning a while after contacting the jig. It finally stops after a few seconds, but I'd rather it stop spinning just as soon as it touches the jig.
Any ideas? Thanks in advance..
Dave

[Mel Fulks]

Some of them are like that,but many just stop the spinning on the extra pattern length lead in. Even though the bearings are sealed the spray lubes seem to help, too.

[Mel Fulks]

Try putting a thin shim between bearing and cutter head,too.

[Mark Bolton]

We build our templates as Mel mentions with a good bit of lead in. You use this area to stop the rub collar before your at the work. All rub collar will spin and they will actually put a dent in your template which is why you want the lead in portion away from the work. It can be a real nightmare with plastic templates.

The larger the rub collar the worse.

[Jeff Duncan]

It doesn't bother me all that much, but I know of some guys who will set up a feather board to keep the bearing from spying at all. Although I believe their reasoning is more to do with trying to maintain as smooth a cut as possible.

good luck,
JeffD

[Peter Quinn]

Push harder. And as Mel astutely pointed out make sure you have proper shim/clearance between bearing and cutter. Perhaps you are getting a little contact and the cutter is dragging the bearing around. It should stop with moderate pressure from the template lead in.

[Dave Winters]

Thanks, all. Yeah, it is a fairly large bearing, 3 3/4". I do have t-bushings top and bottom to reduce as the bearing is 1 1/4" and my spindle is 3/4". It spins freely so I don't think the cutter is dragging the bearing any; when I power off, the bearing spins a little longer after the spindle stops spinning. I do think it's a sealed bearing. Wonder if some bearings spin a little more freely/easily than others....

[Mark Bolton]

Any bearing is going to spin period. There is no way the outer race could even be barely spinning and once you add the mass of the bushing the bearing is pressed into you've got a lot of inertia spinning.

If you can't deal with the spinning the feather board against the collar Jeff mentioned is your only option. There is simply too much friction, lube, and so on, for the collar not to spin or be stopped with very little effort.

What exactly is the problem? Is it causing problems in your work? Or you just don't like it?

[Dave Winters]

Well, it takes a long time to stop spinning after the template contacts it, and so it kinda burnishes a recess in the template.
I made a featherboard for the collar and I think that's gonna work. I'll try to post a pic.
Thanks, all.

[Carroll Courtney]

Since your up in the cold country I say the grease in the rub collar is cold so it will keep spinning some.But once it warms up from work it will stop on contact----Carroll