Any one know of a circle cutting jig for bandsaw, or table saw?

[CODGE]

I need to cut a two-foot circle in oak. Any help is much appreciated. TIA Codge

[Steve Peterson]

[Tom]

Use a plung router with a circle cutting jig. Much cleaner cut than a bandsaw.

[David]

I thought the router was for cleaning up after cutting out the circle on a BS.

Dave

[Andy]

I sure can't picture a safe way to cut a circle with a tablesaw, but if you have a good jigsaw, you can get or make a jig for that, and it will come out almost as clean as a router. Can be as simple as a small flat aluminum bar nailed to the center of the circle and connected to your jigsaw. Router with a circle-cutting jig would be a great way to clean up after a freehand bandsaw or jigsaw cut. Wood magazine just had plans for an easy, cheap, expandable router circle jig - essentially make an offset sub-base out of 1/2" ply with an arm coming off one side, and carefully measure distances from the edge of your router bit to a hole on the arm for the center of your circle. Does that make sense? Easier done than written - basically make a squash-raquet-shaped piece of plywood, with the 'head' the same size as your router base, and put holes in the 'handle'. Good luck, Andy

[Bruce Barnett]

Hmm. Fixed wooden platform with pin 2 feet from the tablesaw edge. Rotate wood on top, and the edge moves towards blade. There was a jig like this in Tolpin's book on tablesaws.

I would have something on top to prevent flyoff. But your hands would be 1 1/2 feet away from the saw.

[BillyBob]

Heck no. You can cut clean circles with a router all day long. All it takes is a piece of plywood bolted to the base of the router with a nail for the center of the circle. Of course there are fancy factory made jigs and fixtures but they don't perform the function any better. I've heard of someone doing a large doorway arch by laying it out in a parking lot and using a router. The key to using the router is making multiple passes. The result is cleaner than any saw can do.

Bob

[Swingman]

Quite possible and there are circle cutting jig designs specifically for the table saw ... but, IME, you have to rough cut the circle first, and it takes a few passes and lots of futzing to get it done. You do get a very clean cut, however.

In my little part of the woodworking world a router and trammel is much preferred over other methods. It is just too easy to make a trammel router base out of 1/4" sheet stock for any router.

[George]

If he's got a bandsaw, it's hands down the best choice.

which requires some imagination, or perhaps a look at this excessively elaborate pay-to-play course Norm built one on TV, too.

A trip to the paper book place should turn plans in most standard texts, though Duginskie's is the one I'd buy or read.

If you like routers, you can move the router with trammels

mount your pivot and leave the router in the table. Recommend spiral bits to help out over the splinter-prone uphill parts.

[Lawrence Wasserman]

Cut a square from your stock on the table saw so that its side is slightly longer than the diameter of your circle.

Then use a single-runner table saw cut-off sled that is at least slightly wider than the radius of your circle. Assuming the runner rides in the left miter gauge slot, the right end of the sled should end right at the blade. Roughly in the middle of the sled from front to back, measure from right edge over to the left the radius of the circle and mark the spot. Find the center of the square you cut (By intersecting diagonals the corners is an easy way) and drill a small hole there. Using a screw that fits snugly in the hole but turns freely, screw the square to the sled at the marked spot. the screw shold not bind the square from pivoting. Raise the blade and cut the corners off the square by running the sled & square through the saw blade. You may want to cut the corners again from the resulting octagon. Now, with the saw running, slowly move the sled towards the blade until the blade just starts nibbling on the underside of the workpiece, and start rotating. After a full turn, move the sled slightly forward again, and repeat until the circle is completely cut.

I have used this method (Which I believe I first saw in one of Cristofero's books) many times and it is safe and makes a perfect circle that requires very little if any sanding. After the first few cuts you will quickly get a feel for how much you can advance the sled for each rotation.

[mac davis]

I went way cheaper...lol I use a pegboard scrap, about 6" x 14" long, with the router stuck on the pegboard with double sided tape and a short sheet metal screw as the pivot.. Almost any size circle is possible, just pick the hole for the pivot point that works, put a straight bit in the router and set it for whatever first cut depth that you're comfortable with... then just set for more depth and run the circle again until cut..

I threw it together when I needed a round top for a 50 gallon drum for my DC... worked so well that I kept it as a "jig" and hung it on the wall...

mac

Please remove splinters before emailing

[BillyBob]

Now that's getting cheap! My first large circle jig came from a source with history. In 1980, I bought some 3/8" exterior plywood to board up my windows for a hurricane. I kept those boards in the attic for years. I finally cut off a piece to make a quick and dirty router circle jig. I think, figuring time value of money, this jig was virtually free.

Our mutual point is that cutting precision circles with a router does not take any precision at all in equipment.

Bob

[remove]

Check out:

- Pin in sliding piece of wood to turn circle about.

HTH Bill

[CW]

Next to the router, that is.

[Bruce Barnett]

And the Binford CircleMaster 7700 - if you can find one.

[mac davis]

Leave it to Ken to come up with a simple solution and then build it nicer than I build cabinets.. *g*

(I wanna be like Ken when/if I grow up)

mac

Please remove splinters before emailing

[bridgerfafc]

I had a job cutting circles out of plastic for museum displays. most of them were 5 to 10 inches or so in diameter. the tolerance was (IIRC) .005". (five thousandths of an inch). I used a jig that took me maybe

15 minutes to build and produced circles that consistently measured within .002" of spec. basically a router trammel with an adjustment mechanism. easy, cheap and accurate.