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Frank McVey
 
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Default cutting circles on a bandsaw

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


"Larry Levinson" wrote in message
...
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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