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Radial Brushing Attempt Without A Lapping Machine


thor447

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I’ve got a case that I’d like to do some radial brushing on.   A lapping machine is far out of my budget, so I tried to improvise this evening. 

I secured the case between a nylon washer and one of my plastic crystal dies.  I chucked it into a drill, and then used that to align it at the proper angle against a brushing wheel.   

It’s clearly not perfect, but I think the concept is sound.   I’ll probably need something different other than a thick brushing wheel to get the desired effect, so I’ll play around with it a bit more. I am encouraged that this may be a workaround to a very expensive tool.  

Obviously a lapping machine can do many other things, but I’m just trying to accomplish this radial brushing for now.  

About two weeks ago I came up with a very crude way of holding a case back centered and allowing it to spin, so I can apply radial brushing to that part. It seemed to work pretty well.

The first two pictures are before my brushing attempt on the case. 

IMG_3675.thumb.jpeg.a350fe0629a376d4ceebc312914c3836.jpegIMG_3676.thumb.jpeg.735dc18901699cde6418535fe5d53118.jpegIMG_3678.thumb.jpeg.964828508cf8ddfdb28599ad3eeb1b39.jpeg

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17 hours ago, mikepilk said:

What kind of wheel did you use for the brushing?

As it turns out, not a correct wheel to accomplish what I was wanting, but it worked moderately.  It was a Bergeon 6085-E2 wheel.  I aligned the case to the corner edge of that wheel in an attempt to minimize the amount of contact (width wise) with the case at any given time. 

Just messing around with an idea, but it got me thinking immediately about ways to improve it.

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  • 1 month later...

Well I happen to score a Horotec polishing vice for a song on eBay.  I was able to call up a friend with a lathe and got an adapter machined so I could mount it to my motor arbor. Horotec sells a reduction die, but the size wasn't compatible with the arbor on my motor. I got this little part made, then drilled and tapped a few set screw holes for the arbor side. I can't wait to destroy a few junk case backs & bezels while I learn how to use it properly!

IMG_3906.thumb.jpg.ab43fe79a670cbacf203bc7cf1d7278a.jpg

 

 

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I usually use 400 grit wet and dry (used dry). 

For straight grain, this is my cheapo set up. It works really well. I stick the case back to the bracket with some Rodico. Running along the wood means I can run it up and down and keep the grain straight. 
If the case back is not absolutely flat, I put a very thin layer of something spongy under the paper (I use some thin packing foam).

For circular grain, I use 400 grit on a stick, and pull it from the centre out.

I don't have space for a bench polisher so have to use a Dremel type tool. With practice I can get a good finish.

20231117_173527.thumb.jpg.c602b85e30184995799526798358e17e.jpg

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5 minutes ago, mikepilk said:

For straight grain, this is my cheapo set up. It works really well. I stick the case back to the bracket with some Rodico. Running along the wood means I can run it up and down and keep the grain straight. 

Sometimes the simplest solutions are the best - consider this copied 🙂

 

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