# How to Cut Small Circles?



## silentblackhat (Nov 29, 2009)

Hey Guys, I'm hoping you all can help me out with this...

I am wanting to cut some small circles that are about 3.75-4 inches in diameter. I have a full size Craftsmen router and the base is bigger than this size so it wont work with the Jasper circle jig. I also have a Dremel tool that has an attachment to go down to this size but the bits will tear up fast and wont do so well with 5/8-3/4 thick MDF.

Are there any other alternative ways out there?


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## bobj3 (Jan 17, 2006)

Hi Kevin

The Jasper you have will do the job just fine you just need to rework the Jssper just a little bit, that's to say drill out the 1/4" hole to a 3/4" or 1" hole in the Jasper and use a brass guide in your router base..no need to bolt the Jasper to your router base..

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silentblackhat said:


> Hey Guys, I'm hoping you all can help me out with this...
> 
> I am wanting to cut some small circles that are about 3.75-4 inches in diameter. I have a full size Craftsmen router and the base is bigger than this size so it wont work with the Jasper circle jig. I also have a Dremel tool that has an attachment to go down to this size but the bits will tear up fast and wont do so well with 5/8-3/4 thick MDF.
> 
> Are there any other alternative ways out there?


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## silentblackhat (Nov 29, 2009)

bobj3 said:


> Hi Kevin
> 
> The Jasper you have will do the job just fine you just need to rework the Jssper just a little bit, that's to say drill out the 1/4" hole to a 3/4" or 1" hole in the Jasper and use a brass guide in your router base..no need to bolt the Jasper to your router base..
> 
> ========


Thank you for the reply. so what you're saying is to drill out the calibration disc to a bigger size(3/4") and use a brass guide? is there anywhere that can show me how to use guides? Im pretty new at routing so im having a hard time picturing how this is all set up


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## bobj3 (Jan 17, 2006)

Hi Kevin

It's very easy. once you have the hole drilled out pop in a 3/4" guide in your router drop the router guide in the hole, drill your stock for the 1/8" center pin, put you pin in place and put your Jasper jig in place and move your router to the right spot and cut your hole out you can also just move the stock and hold the router in one place,.....

To drill the hole to 3/4", pop in a 1/4" drill bit in your drill press, plunge the drill bit into the Jasper than clamp the Jasper down, once you have in dead center pop out the 1/4" bit out and pop in a 3/4" _Forstner_ Bit, this setup must be dead on and you only one shot at it..

guides below
9 Piece Router Template Guide Set


But the easy and fast way is to use a hole saw
http://www.harborfreight.com/catalogsearch/result/?category=&q=hole+saw
http://www.harborfreight.com/10-piece-2-1-2-half-inch-5-inch-hole-saw-kit-with-case-36222.html
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silentblackhat said:


> Thank you for the reply. so what you're saying is to drill out the calibration disc to a bigger size(3/4") and use a brass guide? is there anywhere that can show me how to use guides? Im pretty new at routing so im having a hard time picturing how this is all set up


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## crquack (Oct 10, 2008)

I use this one:

Precision Circle Jig - Lee Valley Tools


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## TWheels (May 26, 2006)

Lee Valley sells Forstner bits of the size of the circles you want.


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## allthunbs (Jun 22, 2008)

silentblackhat said:


> Hey Guys, I'm hoping you all can help me out with this...
> 
> I am wanting to cut some small circles that are about 3.75-4 inches in diameter. I have a full size Craftsmen router and the base is bigger than this size so it wont work with the Jasper circle jig. I also have a Dremel tool that has an attachment to go down to this size but the bits will tear up fast and wont do so well with 5/8-3/4 thick MDF.
> 
> Are there any other alternative ways out there?


Hi Kevin:

Ok, you've got a bunch of options here. Firstly, the trammel method is a bit difficult to handle on small sizes. This is the normal centering jigs that you see. If you chose to go this route, make sure you can walk entirely around your table and keep your hands on the router while cutting the hole. You might pull it off with practice, care and patience.

However, your ideal is Santé's circle cutting jig. 

http://www.lescopeaux.asso.fr/Techniques/clic.php3?url=Docs/Sante_Tripode_Anglais.pdf 

Also, equally successful is the pivot frame.


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## jw2170 (Jan 24, 2008)

silentblackhat said:


> Hey Guys, I'm hoping you all can help me out with this...
> 
> I am wanting to cut some small circles that are about 3.75-4 inches in diameter. I have a full size Craftsmen router and the base is bigger than this size so it wont work with the Jasper circle jig. I also have a Dremel tool that has an attachment to go down to this size but the bits will tear up fast and wont do so well with 5/8-3/4 thick MDF.
> 
> Are there any other alternative ways out there?


Hi Kevin,

The Jasper 400 circle jig will cut holes from 1" to 7" in 1/16"increments.
(this is the round jig, not the oblong jig((200?)))

I have cut 4" holes with a Makita 3612C router with no problems.

I believe it should handle your Craftsman.

James


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## jw2170 (Jan 24, 2008)

bobj3 said:


> Hi Kevin
> 
> The Jasper you have will do the job just fine you just need to rework the Jssper just a little bit, that's to say drill out the 1/4" hole to a 3/4" or 1" hole in the Jasper and use a brass guide in your router base..no need to bolt the Jasper to your router base..
> 
> ========


Hi BJ,

I like your copy of the Jasper jig.

How did you line up the holes? taped the old one to a blank and drilled through both with a drill press? Or was there some other method?

I would like to try but don't want to ruin my existing jig. :nono:

James


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## bobj3 (Jan 17, 2006)

HI James

Thanks
You got it, it's hard to screw it up, just nice and slow...

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jw2170 said:


> Hi BJ,
> 
> I like your copy of the Jasper jig.
> 
> ...


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## harrysin (Jan 15, 2007)

A relatively easy to make circle jig like this one goes steplessly from about a 3/4" hole all the way up to over 20". The spacing, diameter and height of the rods are determined by the particular router.


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## jw2170 (Jan 24, 2008)

harrysin said:


> A relatively easy to make circle jig like this one goes steplessly from about a 3/4" hole all the way up to over 20". The spacing, diameter and height of the rods are determined by the particular router.


Harry,

I made your jig to suit my Ryobi router, but did not secure the rods properly.

I am going to modify to take 1/2" threaded rod for the makita.

I have not set the formica yet. What glue did you use?

James


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## harrysin (Jan 15, 2007)

jw2170 said:


> Harry,
> 
> I made your jig to suit my Ryobi router, but did not secure the rods properly.
> 
> ...


Don't waste your money on 1/2" threaded rod James because it wont fit, the Makita 3612/C takes 12mm rods. How about a photo of the jig that you made, I'm sure that a little re-work will fix it. This shot shows how I mounted the rods into a hardwood (Jarrah) block. I drilled a 1/4" countersunk hole intersecting the 12mm hole for the rod, then ground a flat on the rod before tapping it into the tight hole. I then poured super strength two part epoxy (Araldite) into the hole and this made sure that the rod stayed put.
For gluing Formica I use contact adhesive gel, it's so much easier to use than the liquid.


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## Al Robins (Jul 13, 2009)

James....I was lucky and didnt have to use the jarrah block, I just drilled two holes, countersunk them and used thin spacers so the rods ran parrallel to Harrys board....I' ll take a photo when it thaws out here and post it.....Regards....AL


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## Al Robins (Jul 13, 2009)

Heres the phots of my jig for circle cutting James....note the thin packing piece between the board and the jig....if you dont use the strip the rods tend to point down and you cant get the router base to slide on the rods. Regards......AL


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## jw2170 (Jan 24, 2008)

silentblackhat said:


> Hey Guys, I'm hoping you all can help me out with this...
> 
> I am wanting to cut some small circles that are about 3.75-4 inches in diameter. I have a full size Craftsmen router and the base is bigger than this size so it wont work with the Jasper circle jig. I also have a Dremel tool that has an attachment to go down to this size but the bits will tear up fast and wont do so well with 5/8-3/4 thick MDF.
> 
> Are there any other alternative ways out there?


Hi Kevin,

Sorry for hijacking you thread, but you can see there are a number of ways to solve your problem. All of them should work with your craftsman router.

have you found the answer you were after?

James


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## jw2170 (Jan 24, 2008)

harry, I will post pictures this week end as I cannot access the shed during the week. (dark when I get home from work).....

Thanks also Al.

James


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## jw2170 (Jan 24, 2008)

crquack said:


> I use this one:
> 
> Precision Circle Jig - Lee Valley Tools


I believe this is the Jasper 400. same as mine.

James


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## bobj3 (Jan 17, 2006)

Router Accessories, Circle Guides, Router Base Plates, Houston, TX Butterfly Template

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jw2170 said:


> I believe this is the Jasper 400. same as mine.
> 
> James


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## GTVi (May 14, 2010)

Go the Aussies for using necessity as the mother for invention...I'm gonna make me one of those circle cutters just for fun.


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## Al Robins (Jul 13, 2009)

Bill, you may have trouble adapting that circle cutter to a Ryobi router unless you have the Ryobi fence.....if you do....go for it, the principal will be the same. Regards......AL


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## jw2170 (Jan 24, 2008)

Al Robins said:


> Bill, you may have trouble adapting that circle cutter to a Ryobi router unless you have the Ryobi fence.....if you do....go for it, the principal will be the same. Regards......AL


AL,

You do not need the fence if you use a hardwood block as Harry did.

I used a wooden block and I need to secure the rods in a better manner. I will take a clue from Harry and file a groove and glue in.

James


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## harrysin (Jan 15, 2007)

Thinking back James, I now recall that I ground a deep "V" groove.


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