# Small dia. circle jig



## dwall174 (Feb 15, 2010)

Doing a search here on the forum I came across this old post showing a DIY small dia. circle jig that may work for me! Router Forums - View Single Post - Small diameter circles. 

I have a Bosch 1617/1618 EVS combo with a RA-1054 edge/circle guide, Just wondering if anyone has made an adapter (like pictured in the linked post) for the RA-1054 to make smaller than 4" dia circles?

Doug


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## JOAT (Apr 9, 2010)

If you are talking about making the hole all the way thru, I just use a hole saw.


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## cjhilinski (Apr 25, 2017)

On the few occasions where I needed to route circles smaller than 4 inches, I would do this. Set the router circle jig to make (for example) a six inch circle and cut that out of a piece of stock. Throw the circle away and use the remaining/resulting "donut hole" as an edge guide. Put the router inside the donut hole and follow the inside edge. You can get as small a circle as you can do the math for by making your own circular edge guide. Did I explain that okay?


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## dwall174 (Feb 15, 2010)

JOAT said:


> If you are talking about making the hole all the way thru, I just use a hole saw.


Yeah to bad it wasn't that easy!

I'm looking to make some trunnions & matching radius grooves for a tilting table on a disk sander.

Doug


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## dwall174 (Feb 15, 2010)

cjhilinski said:


> Put the router inside the donut hole and follow the inside edge. You can get as small a circle as you can do the math for by making your own circular edge guide.


Yeah that could work, As long as I could figure out the math needed correctly.

I would need to figure out three different size patterns, One for the inside radius, One for the outside radius, Then one for the matching radius groove.

Doug


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## Cherryville Chuck (Sep 28, 2010)

Maybe this thread will be helpful: http://www.routerforums.com/general-routing/31313-circle-trimming.html The world's simplest circle jig is described in post #2.


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## dwall174 (Feb 15, 2010)

Cherryville Chuck said:


> Maybe this thread will be helpful:


Chuck,

Thanks for the link & moving my post!

Doug


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## CharleyL (Feb 28, 2009)

Are you one of us who bought a CRB7 jig? These are similar to the one in your link, but can do many other things as well. Since I have a CRB7 I would use it instead of making one. The Jasper circle jigs are also very handy for cutting circles of many sizes with a router.

Charley


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## dwall174 (Feb 15, 2010)

CharleyL said:


> Are you one of us who bought a CRB7 jig?


No not me, However I have thought about getting one?
Just trying to justify the cost since my Bosch RA105 will do a lot of the same functions as the CR87. 

Doug


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## chessnut2 (Sep 15, 2011)

dwall174 said:


> No not me, However I have thought about getting one?
> Just trying to justify the cost since my Bosch RA105 will do a lot of the same functions as the CR87.
> 
> Doug


I've been wanting the CRB7 also. It costs a lot, but when you need it, you need something that's fairly safe.


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