cutting circles on a bandsaw

I know there has to be a simple answer:
I made a small circle-cutting jig from some MDO and a 1/4" bolt, with the bolt 1.5" from the edge of the jig. I want to end up with 3" circles. The problem is that if I make a blank big enough for a 3" circle, I can't fit it between the pivot bolt and the blade, and if I make the blank much smaller, I end up with large flat spots on the circle. What am I doing wrong?
Thanks in advance.
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You have to guide the blank into the blade by using a runner in the miter slot of the saw. Fine woodworking has a plan for a circle cutter that uses the miter slot and works really well. Maybe someone has a link???
Tim

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Rockler sells a kit for a circle cutting fixture. You supply the MDF or plywood and a runner. It is adjustable for any diameter up to about 24" IIRC. It is about $20 The fixture was featured in their magazine, Woodworker's Journal. Ed
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Ed, Tim: put a runner on my jig and it worked like a charm ... and all out of scrap. thanks for the help.
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Have you considered using a hole saw bit for a drill press? Just a thought since its only a 3" circle...
Larry Levinson wrote:

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I have a circle cutter for the drill press. There's a keyed rod on it that tighens a cutting edge using an alan wrench. You need to turn your drill press all the way down to 500 rpm or less as it can run like a frightening hot sucker. It does make a beautiful wheel. It can cut wood maybe 1.5" thick. I think I got it at Harbour Freight in Knoxville, TN for cheap. The bandsaw is better at bigger stuff, and requires an accurate diameter-sized cut on the perpendicular.
If you figure another way use the thin bandsaw blade for your needed 1.5" dia. circle and feed carefully and watch your fingers. Now that I think about it, the circle-cutter on the drill press sounds safer. On Sun, 02 Nov 2003 19:16:39 -0700, Grandpa <jsdebooATcomcast.net> wrote:

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Hi Larry,
For circles this small, simply cut a piece of ply/mdf - around 3/8 - 1/2" thick the same size as your BS table. Start the saw and push the ply/mdf through the saw until it completely covers the saw table, forming in effect a false table top. Switch the saw off.
Depending on the size of your table top, you can either clamp it in place or, if the clamps will get in the way, slip some double-sided tape between the false and real table-tops to hold them in place. Make sure the table is dust- and oil/wax-free, or it won't stick.
Taking the normal infeed position as being 6 o'clock, pencil a line from the cutting edge of the blade out to 3 o'clock on the false table, so you should have a line extending from the edge of the blade and at right angles to it.
Measure along this line - in your case - 1 1/2" mark the spot and tap in a small round nail, (16g or so, it's not crucial) until it contacts the real table. Snip it off about 1/8" above the table, using a pair of sidecutters or pliers, leaving a sharp point. If the point isn't sharp enough, you can dress it with a small file or oilstone until it is. This, of course, will be your pivot.
Feed the blank - probably about 4" square in your case - into the saw, taking about 1/4" from the LHS with the majority of the blank standing out to the right of the blade. Obviously, it won't lie flat on the table because the pivot point is sticking up, but that doesn't matter, it'll ride over it. Once you have fed it through sufficiently far for the centre of the blank to lie roughly above the pivot pin, give the blank a thump right in the centre with your fist or a hammer to seat it firmly on the pin. Continue to feed the blank, pushing gently on the LH corner nearest you and you will find that it will start to rotate on the pin, giving you a perfect circle.
Quick and dirty - yes. But it gives great results without the need to drill the blank and it only leaves a small pinprick in the finished circle. It's very quick to do - you can turn out several circles per minute, and best of all, it's absolutely free. And that's important to a Scotsman!
HTH - let us know how you get on.
Cheers,
Frank

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Frank, I did essentially what you suggested, though with a few differences. I took my ``jig'' and added a runner to the bottom and a stop to the end. (I actually want the center hole to go through so using the 1/4" bolt and drilling out the hole is a benefit, not a drawback.) To cut the circle, I put the blank -- 4" good guess -- on the jig, slide the jig and blank onto the table and into the blade, and when it hits the stop at the end of the jig, start turning around the pivot ... thanks for the help.

Larry Levinson Talking up to the vocal ... LLevinson*Bloomberg.net (remove the star etc ....)
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A much more elegant solution than mine if you're turning out a lot of them. Glad to be of help.
Cheers,
Frank

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