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here is the circle cutter I made based upon the LMI jig they had designed by Richard Schneider - his was made to use a blade to score the inner/outer edges, then remove the trough with a chisel. This one uses a PC 7310 lam trimmer instead, using downcut bits.

the orange piece is made to fit your trimmer or dremel if you wish. Simple enough it needs holes to mount the router. Then it needs two holes which are threaded, I used all 1/4 20 on this, easy to get knobs and such. In these holes mount the 2 rods. The two red pieces are your adjustment pieces. Each has two 1/4 holes for the rods to slide on, then drill holes into those holes, tap 1/4 20 for the lock knobs. Thru the centre of the 2 red pieces is another set of holes. The outer red piece gets tapped for the adjustment rod to turn. The inner piece gets a 1/4 inch hole, and two lock nuts secure the rod against either side of the hole. put in a 1/4 20 threaded rod and an adjustment knob, mines off a gretsch !!! I added the black piece in order to gethte pivot pin to slide under the lam trimmer, and enable smaller diameter circles. The pin is again 1/4 inch. I used all stainless rod here. You should be able to make this up in a couple hours max, and your rosettes and soundholes will love you for it !!

The only advice I can give, is drill all aligned holes together at once, and once one hole is drilled, put a rod into it to hold hte pieces together while you drill the next - helps keep it all aligned. Oh yeah, almost forgot, all pieces are UHMW plastic, Lee Valley, cheap.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Hey Tony, Thanks for the pictures

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Tickle your guitar daily, and it'll tickle you back.

That's a great-looking tool! Thanks for taking the time to post this.

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John Cavanaugh
Saint Paul, MN
"What could possibly go wrong?"

For those who still may be confused as to how it works, you lock the black knob closest to the adjusting Gretsch knob - now the adjuster knob, Gretsch, moves the bit of the router in or out depending on rotation - every full turn is 50 thou, 1/4 turn is 12 thou etc .. you can then lock the other blk knob to secure everything, although most times I dont bother, the threads are pretty snug and dont move at all.

Get the stew mac action gauge to set the bit height - its great, reads in thous, so easily set for 50 thou shell or whatever.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Nice Tony...thanks for posting. I have lots of UHMW and now have a project to use it.

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JJ
Napa, CA
http://www.DonohueGuitars.com

[QUOTE=JJ Donohue] Nice Tony...thanks for posting. I have lots of UHMW and now have a project to use it.[/QUOTE]

Same here! I already have my circle cutter from hell but I like the micro-adjustment on this design...

Thanks Tony!

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

Tony, that's a manly tool! Thanks!

Tony, thank you for the pictures and explanation. This one is going to be built in my shop. Thanks again.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

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Thanks for the pics and explanations Tony!

Thanks for posting this, Tony. I'm going to make one just like it.

Now, if someone were totally nether-end-of-the-alimentary-canal retentive, he could draw up a scale for that micrometer adjustment. Here's the one I plan to use, showing increments of .003:

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D..

Not a bad idea Dennis ... I think I might take a Sharpie and color every fifth groove on the knob. Good stuff. Get a finely knurled knob and the work is half done for you !!!!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"