Introduction: Super Simple Bandsaw Circle Jig
I wanted to cut some circles on my bandsaw so I needed a jig. I looked at commercially available circle jigs, and lots of designs for diy circle jigs, some really complicated and most involving making a plywood cover for the whole table and various sliding its and bobs fitted to it.
My bandsaw is really quite rubbish and the machine itself cost less than a commercial jig would, and probably less than the bits for a complicated diy jig from a plan, so I decided to have a go at making a jig myself keeping it as simple and cheap as possible, by using scrap wood I already had, and a plan from my own brain.
I cut a piece of 12mm ply and drilled a hole in the centre of it using a drill press to ensure it was exactly square with the ply. Then I attached to cut offs from another project which I knew to be the same height.
I screwed a decking screw into the drilled hole to cut a thread in it, then removed it and ground the threads off the tip to make it into a point, then re-inserted it into the hole.
The jig works by clamping it to the bandsaw table, with the screw point in line with the with the blade and the distance from the blade as the circles radius. The piece to be cut slides under it and is held in place by screwing the screw down until it pins the workpiece in place, the point embeds into it and provides a pivot point, either in the piece itself or a sacrificial scrap piece stuck to it with double sided tape.
It worked pretty well and even worked with the table tilted to cut some pieces for a small segmented bowl, I found that screwing the pin down too hard held the piece to the table too tightly making it hard to turn the piece, but screwing down into the piece to punch into it then backing the screw out a fraction of a turn worked really well. The photo shows it cutting a piece of maple at an angle for the bowl.
5 years ago
what do you aligns he pin with when you say " the blade"? the front of the blade? the middle of the blade? halfway across the tooth length? and do you have to consider the set of the teeth or width of the blade? I have tried similar things but failed to find the sweet spot and the kerf started pulling and twisting my blade in odd directions
Reply 5 years ago
You would measure from the front of the blade and cut on the outside of the line as you would for any other cut, although the blades I use are only 1/3 mm thick so you'd probably not notice any difference.
It sounds more like your blade is no good, a decent sharp blade won't drift at all but a poor quality or used up blade won't cut straight.
9 years ago on Introduction
I must have watched 90% of the woodworking videos on Youtube (weird obsession of mine), and I've never seen anyone do this. I've given much thought into how I would build a circle jig, and this idea never even crossed my mind. (I haven't built one, yet. What I have been doing is to just put a screw through the stock so the point is barely poking out, and then just hold it against my sled while turning it.)
Even though this simple idea is already burned into my memory, I have favorited for props. Thanks for sharing this great idea.
Reply 9 years ago on Introduction
agreed! couldn't have said it better myself