Band Saw Circle Jig

[rickc]

I built a "zero clearance" table for my bandsaw, and incorporated a scale on the top to use as the basis for a circle cutting jig. To use the jig, I had a base with a brad through it, to which I attached the stock I was going to cut. I would insert the brad point in a hole on the corresponding point of the scale, and go about business. Sounded good - BUT when using it this weekend, it bound my bandsaw blade. I was cutting pine, on a Delta 14", 1/2 hp saw with a 1/4" blade. Radius was 2 3/4". When I took the tock out and tried cutting freehand, it worked fine. Anyone have a jig that works for them?

 

[mshel]

Rick,

I have a circle cutting jig that I made from some plans I got somewhere and although I have cut numerous circles using it, if the setup is not just right, it will bind. I believe the intersection of the leading edge of the blade and the stock is important. Don't know exactly what that is but I do know it's important to the jig working right. You might play with the positioning of the jig in relation to the "intersection point" and see if it will work. Hope this helps.

MIke

 

[Monty]

Here's a link to a bandsaw circle cutting jig I posted here yesterday...

linky


That's for bigger circles, though. That radius doesn't sound too tight... not sure what the problem was.

Another alternative would be to think about free-hand cutting close to the line, then use a circle-cutting jig on the disc sander, maybe?

 

[DaveO]

Could your brad be out of plumb, causing the stock to move forward out of the true circle somewhere during the rotation. It sounds like your blade width is correct for the radius, and your freehand cutting test proves that the saw can handle the cut. That is the only way I can think that it would bind. Dave

 

[rickc]

Thanks for the suggestions folks. Something in my gut tells me I need to look at the alignment of the brad, and also the intersection point. Ah - something to do this week.

 

[SteveColes]

ow, ow, I know this one, can I answer, can I? :hello2:

The frame the blade and the pivot point have to be on a straight line. Or another way of saying that, is that a line drawn from the pivot point to the center of the blade must be perpendicular to the face of the blade.


|----------------------P

 

[rickc]

As I said I think that is the problem. I have this sinking feeling in my stomach that the pivot hole is aligned with either the center or back of the blade. Will check it out tonight or tomorrow. Your diagram only makes that sinking feeling a bit deeper!:-( Thanks for the information!

 

[sapwood]

Minor Hijack Here:eusa_shhh

The best choice for cutting circles is:

Bandsaw Jig?
Router Jig?
Drill Press with bits from 1" to 4 ft;-)

Of course, that asssumes you have these tools:!:
Note, I haven't made either jig--but I could be influenced!

Sapwood

 

[DaveO]

I'm gonna sick the Dept. of Homeland Security on you for that hijack. I like to use a router jig, it is so easy to make and simple to set the radius, and very precise. I used one yesterday to cut a 4' dia. table top. Dave

 

[rickc]

I have a router jig as well. This past weekend's challenges were a 5 1/2 " circle and a 2" circle - a tad bit on the tight side for a router. :roll: Quite frankly I was looking forward to trying out the band saw jig so much, I forgot all about the drill press set up I have until mentioned here! C'est la vie!

 

[Phillip]

roger, how about that new handplane and a file or rasp? for the larger radii at least...

phillip

 

[Phillip]

oh, and for the smaller radii, stewart macdonald (stewmac.com i believe) sell a super nice router base setup for dremel and other rotary tools. can't live without mine.

phillip

 

[gator]

I have a large BS table extension set-up ala what Norm has used in the past. The one thing to be careful of is the alignment of the pivot point and the leading edge of the blade, they have to be dead on. Other than that, it has worked well for me.


George

 

[woodworker2000]

If I'm reading these posts correctly, the pivot point needs to be aligned with the leading edge (teeth) of the bandsaw blade? If that is the case, does that mean that the jig has to be designed for/used with a specific bandsaw blade or at least a specific size?

 

[gator]

On my table, I have a bar on the underside that rides in the BS table's miter slot. I can move it side to side before clamping it down so I can align the pivot point with the leading edge of the blade.


George