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Paul Engle
11-01-2006, 3:50 PM
In making a circle guide for band sawing blanks, is the pivot point set to lead the teeth on the saw or even with the leading edge of the teeth? I've always done flat work using router and arc and not sure on cutting out blanks using a circle guide. Any help here will be greatly appreaciated.:D

Jim Becker
11-01-2006, 4:22 PM
Frankly, I see no need to cut a "perfect" circle for turning blanks...I use a compass to mark the circle and then just free-hand it out. The blank is likely going to deform over time due to moisture loss and become slightly oval, anyway. Much of the time I actually don't cut the blanks in to neat circles...I put the wood on the lathe between centers to find the best orientation and then true it up in that orientation for actual turning.

So...just draw on the circle or use some shop-made plastic disks screwed to the blank to "eyeball" the cut. That's all that is necessary.

Frank Kobilsek
11-01-2006, 4:50 PM
Paul
Keep it simple buddy. For bowl/platter blanks you don't have to be perfect. Cut a circle from something that is relatively stiff. Most of mine are 1/4 or 3/8 plywood and have many cut from corrugated plastic (old political signs). One hint, if you want to make a 12" bowl and you try to cut a perfect 12" blank you'll end up undersized on the finished product. I jsut can't get everything on the same perfect center start to finish. Therefore make your templates 1/8 to 1/4 oversized. Now to use them:

Lay you log half flat side down and center the template. Drive a nail thru the template into the log, but not too far. Follow the template at the band saw. IF you tear up the edge of the template it just doesn't matter. When round at the bandsaw remove template. Flip blank and do your best to center the template on the flat side and tap the nail in marking center.

One other trick: on the convex side find your center mark and drill a hole with a 1" fostner bit maybe 3/4 deep. This gives your tail center first more solid wood to bite and makes it easier to form a larger diameter tenon with having to cut it off thus loosing your center on the bowl bottom.

Lastly I hope your not an old vetern and think I'm a idiot for explaing this when you were talking about something completely different. It took me a few tries to get the hang of roughing with the blank saw. Much better than roughing with the chainsaw.

Frank

Bob Opsitos
11-01-2006, 4:55 PM
I use various size cardboard templates that I nail to the blank and then I saw around the outside of the cardboard. Get's 'em round enough. And it's quick to make a new one to accomodate a blank that doesn't conform to the ones I have on hand. Make with compass; cut out with x-acto knife.

Only bad part of the cardboard is the center hole can get larger than ideal for the small nail I use. In that I expect plywood/hardboard has the advantage.

Bob

Andy Hoyt
11-01-2006, 5:02 PM
I use 1/4" plywood and screws. The screw holes don't seem to enlarge themselves all that much.

Don Baer
11-01-2006, 5:19 PM
Here's som pictures of one I made for cutting a 32" round table top. It has holes every 1/2" or so. I use a pop rivet as the holder and line it up to the leading edge of the blade. Now I use it to round my blanks and get perfect circles which are very important when making 12" blankes for a 12" lathe.

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Bernie Weishapl
11-01-2006, 9:25 PM
My wife cut me a batch of card board circles out of a refrig box from 4" to 14". I just the circle on the wood draw a circle with my carpenters pencil, go to the saw and saw it somewhat round. Doesn't need to be a perfect circle as Andy Hoyt told me one time. He said that is what the lathe it for.

Paul Engle
11-02-2006, 8:04 AM
Hey yall ...thanks for the feedback, I tried Don's approach on a 10 in blank and it ran REALLY smooth right off the saw. Since I have a ton of templates for my taxidermy trade I really wanted something that would elimanate more clutter and this worked very well for 8" and up on a 3/8 " skip tooth blade. Being a machinist classicly trained , I sometimes get anal about precision ( my wife is laughing at me :o :D ) and this 10" bowl being my first on new lathe, needless to say I was anxious. Soon as I get my camera back from #1 daughter I will post some pic's of the saw and the 10" walnut burl bowl.Now wont have to raid wifes kitchen as I have been using her plates & etc for templates.