Shimming a router guide bearing.

[Roger Feeley]

I’m going to route some cherry using a hand held router and a flush cutting bit. The whiteside ultimate bit is 7/8” dia on a 1/2” shaft. My usual procedure is to leave just a bit of wood for one finish pass to avoid burning. That’s pretty easy on straight cuts and a router table. But this will be hand held using a mdf template.

—I was thinking about running a couple of layers of masking tape around the template to build it up.
—I could somehow build up the guide bearing.
—maybe I could start with a much smaller pattern bit with an over size bearing. Once I establish a ‘track’ I can revert to the big dog.

The first two ideas kind of scare me a bit.

[Richard Verwoest]

A bigger guide bearing?

[Richard Coers]

You used to be able to get a ring made of delrin or some kind of white plastic, that pressed over the od of the bearing. No idea if those are still available.

[Alan Schwabacher]

You can get sets of bearings for this purpose or to adjust rabbet size, as suggested by Richard above. Infinity Tools RB-156 is one option of many.

[Warren Lake]

I used to get sleeves made my for my bearings. .020 over the last one

[Jamie Buxton]

I’ve used a couple of layers of duct tape to make a guide bearing bigger. It works. IIRC I started the router with the taped bearing in contact with the template, so it is only spinning at a few revolutions per second.

[johnny means]

I'll just tip the router outward ever so slightly. Sometimes I'll tape a shim to the router base to help hold the angle.

[Lee Schierer]

Maybe I'm missing the obvious, but why not put layers of tape on the pattern? Even if there are wrinkles in the tape, the final clean up pass should smooth things out.

[Roger Feeley]

For those suggesting a bigger guide bearing:
I need a bearing that goes over the shaft of the bit.
id: 1/2”
od: 1”. (The flush bearing is 7/8”)

[Dan Hahr]

Just put a couple strips of painter tape along the template edge. A quick final pass will remove a few thousandths and any burning.

Dan

[Prashun Patel]

I would do as Dan suggests. Tape on the template edge. Johnny, you are a brave man!

[glenn bradley]

I use one layer of blue tape on the template. This is a little thicker than a sheet of printer paper and allows me to use the upper and lower bearing without a lot of fuss. Two layers would be fine as well but, sometimes the added thickness can make things mushy. The final pass cleans it up either way.

[roger wiegand]

I make a pencil line on the workpiece from the template, saw to the outside of the pencil line and then take off the width of the line with the router. Seems to work better for me than trying to hog a lot of wood off with the router.

[Roger Feeley]

I thought about that. The pattern is ultra light mdf which isn’t much more than compressed sawdust.

I manned up this morning and just took it slow. I’ll get through this. If I could have found a bearing that’s 1/2x1x1/4, I would have bought it. Honestly, I thought it would be easy to find. Silly me.

anyway, I’ll have the job done this afternoon. It’ll take longer because I have to be more careful but that’s ok.