My Math teacher might be proud of this

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Blog entry by John Nixon posted 07-06-2007 01:59 AM 1904 reads 1 time favorited 9 comments Add to Favorites Watch

With the aid of my motorized router lift, I can create medium to large circles on the router table easily.

Forget that router trammel or bandsaw circle jig, with this method, you can make circles on your router table with no dust and no fuss.

This method is safer, cleaner and more accurate than many other methods. If you have a router table with a miter slot, check out this setup!

The scale is based on the pythagoream thoreom. THe hypotenuse of a right triangle is changed to alter the radius of the circle being cut. The scale is designed to display a radius, but is graduated using the pythagoream thoreom.

The Video Explains a lot (and note the awkward pause at the beginning…LOL) :

To see the rest of the details for this project visit:

The Scale:
Scale Explained

-- John Nixon - Buffalo, NY -

9 comments so far

View Karson's profile


35197 posts in 4877 days

#1 posted 07-06-2007 06:11 AM

Very interesting jig. and a nice process video.


-- I've been blessed with a father who liked to tinker in wood, and a wife who lets me tinker in wood. Appomattox Virginia [email protected]

View Damian Penney's profile

Damian Penney

1141 posts in 4467 days

#2 posted 07-06-2007 03:10 PM

That’s a pretty cool jig, wouldn’t it be quicker to setup something similar on your bandsaw though?

-- I am always doing that which I can not do, in order that I may learn how to do it. - Pablo Picasso

View John Nixon's profile

John Nixon

189 posts in 4539 days

#3 posted 07-06-2007 03:46 PM

Thanks for checking out the video Karson & Damian.

Damian – yes, it probably would be easier to cut the circle out on the bandsaw. The advantage to setting up on the router table would be in making decorative edges, or inlayed rings. To be honest, I hate my bandsaw which is probably why I went to the router table to begin with.

-- John Nixon - Buffalo, NY -

View Bill's profile


2579 posts in 4638 days

#4 posted 07-06-2007 05:13 PM

Nice job John. At first I thought you were just turning circles, until I realized you were also lowering the work each time you went around.

It looks like you could use your same jig on the bandsaw as well. Like you said, you can put an edge on the piece with the router while making the circle.

Did you clamp the bar in place? I did not see that, but thought you must have to keep the circle cut even.

-- Bill, Turlock California,

View mot's profile


4926 posts in 4513 days

#5 posted 07-06-2007 05:28 PM

Nice video John. Always excellent information and presentation. Thanks!

-- You can discover more about a person in an hour of play than in a year of conversation. (Plato)

View John Nixon's profile

John Nixon

189 posts in 4539 days

#6 posted 07-06-2007 05:44 PM

Hi Bill, thanks for checking out the video.

I am actually raising the bit into the wood with a foot pedal connected to my motorized router lift. I can gradually raise the bit height and eventually cut the circle.

I do clamp the scale into the miter guage by way of that allen bolt on the end that separates the scale as it tightens and locks it in place (it’s a pretty snug fit to begin with, and tightening the bolt just seals the deal).

Thanks for the compliments Bill, I’m glad you like it.

-- John Nixon - Buffalo, NY -

View John Nixon's profile

John Nixon

189 posts in 4539 days

#7 posted 07-06-2007 05:45 PM

Thanks Mot! I appreciate you taking the time to check it out.

-- John Nixon - Buffalo, NY -

View john's profile


2380 posts in 4858 days

#8 posted 07-06-2007 06:38 PM

I sure wish i had high speed.

-- John in Belgrave (Website) ,

View John Nixon's profile

John Nixon

189 posts in 4539 days

#9 posted 07-06-2007 06:59 PM

Hi John,

You could download the video from Google and then watch it when it’s finished downloading. I’m not sure how big the download would be, but you could start and then go have a sandwich.

Here’s the link to the video on Google – there’s a download link on the right:

BTW – I am a big fan of your work. Absolutely amazing creations you come up with. I built a bird house with my 6 year old son last week, and he had a blast. Nothing close to your mansions, just a little 5 room joint for the local feathers.

-- John Nixon - Buffalo, NY -

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