Different Style Circle Jig

[Greg Brimer]

I made a different circle jig and it works really well. The center to center distance on the rods for the craftsman router that I have is 4".106. I used 8mm rods. The base is oak.

Greg

[Rob Keeble]

Greg you cannot be aware that idiots like me frequent this forum. Can you show us how this works i am lost. I can understand the build but how do i use it to make a circle? I have scratched and scratched and my brain still cannot get it. I am pretty sure it will be simple when you show how.

[Jim DeLaney]

Greg you cannot be aware that idiots like me frequent this forum. Can you show us how this works i am lost. I can understand the build but how do i use it to make a circle? I have scratched and scratched and my brain still cannot get it. I am pretty sure it will be simple when you show how.

Thanks, Rob! I guess I'm not the only 'slow' one here, because I couldn't figure that one out either. I could see using the rods & bar as a fence, and also using the center pin/screw in the bar as a pivot, but I have no clue what the plywood piece is for.

Help us dummies out, Greg!

[Ron Jones]

It appears that I'm in pretty good company when it comes to being "slow" on this one.

[Ed Thomas]

The bar is fixed to the ply and there is a range of adjustment on the rods. Move the pivot to the next hole in the ply as required.

(Took me a couple of secs to get it) If you think this is ... I've got a couple of cirle jigs of my own ...

[Jim DeLaney]

The bar is fixed to the ply and there is a range of adjustment on the rods. Move the pivot to the next hole in the ply as required...

But then, what do you do with the ply? Does it pivot around a point/hole in the workpiece, or what? I can see using the center of the aluminum bar as a pivot point (center of the circle), but still don't see what the purpose of the plywood is.

[Ed Thomas]

... but still don't see what the purpose of the plywood is.

I'd guess it's an alternative to longer rods.

[Greg Brimer]

Greg you cannot be aware that idiots like me frequent this forum. Can you show us how this works i am lost. I can understand the build but how do i use it to make a circle? I have scratched and scratched and my brain still cannot get it. I am pretty sure it will be simple when you show how.

Rob,
The board has different holes in it for a pin to pivot on. It can do bigger circles while using the different placements for the pins and you can do all the between sizes by sliding the router down the rods. You measure from the edge of the cutter to the center of the pin and that is your circle size. The main purpose of the board is for adjustment of different sizes.

[Greg Brimer]

I'd guess it's an alternative to longer rods.

Yes. With the different hole placement you only have to have one set of rods for the many sizes you can do. 2" to 15" circle can be done.

[Ed Thomas]

Thanks. Hadn't noticed that this also lets the pivot get closer to the bit for smaller circles. I had a jig about 30 years ago that used all-thread through the bar. Could do a +6' circle, but not smaller than about 8".