Jasper jig description says

[palmtree]

"The jig has an easy-to-read scale that is calibrated for a 1/4" router bit." How easy is it to use with 1/2" bits?

[cjd]

How good are you at subtracting an eighth inch from your required cutout measurement to figure out which hole to use?

C

[palmtree]

How good are you at subtracting an eighth inch from your required cutout measurement to figure out which hole to use?

C

I think I am up to the task! Just wanted to make sure it wasn't too tricky before I bought one.
Thanks

[Brian Bunge]

Chris,

That would be 1/4". Subtract 1/4" from the diameter of the actual bit used and that is the difference between the actual diameter of the hole you want to cut and where you actually have to put your pivot pin. For instance, if you need to cut a 7" hole using a 3/4" bit then you will actually have to put your pivot pin in the hole for a 6 1/2" diameter cut. For a 1/2" bit you'd use the 6 3/4" hole, etc.

Your 1/8" difference is in the radius, not the diameter.

[cjd]

Well, yes.

You need radius to use the circle jig, so that seemed to me the pertinent number. :P

C

[Brian Bunge]

With your typical circle jig you'd need the radius of the circle, but not when you use the Jasper. You go by the diameter that you want to cut and adjust the pivot pin based on the diameter of the bit you are using.

[dyazdani]

I think the back of the package has an equation in case you forget exactly how to do it...

[Brian Bunge]

Yes, it does. I've been using the Jasper Jig for years now so thankfully I don't need to look at the instructions anymore.

[cjd]

oh! crazy.

I've never used a genuine Japer jig. Always made my own.

Glad ya piped up then.

C