5 Attachment(s)
Need to plasma cut some circles/holes soon. Cheap magnetic circle plasma jig.
My son and I have a personal project where we need to plasma cut some holes. We have free handed them for a long time, they never quite look perfect until you hit them with the grinder. I thought about some slipping line/cord on a pivot point. Gino's Jeep in the gallery, we freehand cut the headlights with the plasma. Figured time to make something to help with cutting holes.
We looked all over the internet (tons of router plans). On plasma circle cutting, too much work and/or not enough details. I did looked at plasmahelper.com days ago, if a customer wants to pay for it (or we cut more holes), that's the one I would get for sure. But this is for a camping project.
I looked all over and found a pair of HFreight magnetic hangers of some kind, bought a pair for like $2 awhile back, for this idea actually.
We stuck it on the little drill press and removed the rivet. Then we dropped in a 8mmx1.25x2.25" (could not find a 5/16" the length I wanted and figured the cutter would feel more at home with metric).
So now we had a base and a center post/pivot-point that will stick the ferrous metal.
Looked on the internet some more. Everything needed two rods to get around the center post and pivot. I had some strips of cutting boards from a food place in the back. Had the idea to make a base/pivot part, and a torch guide with a set of forks to slide in and out and lock down (around the center post). Used a four screws to make if slide straight. I will use screws through the forks if it starts to slide on me, but so far it locks down quite well. And I spun the crap out of it.
Rivet done, the magnet is 2 5/8" across. Looked up the hanger.
http://www.harborfreight.com/catalog...=magnet+hanger
Attachment 6606
The bolt, I ended up with washer on the bottoms to get the base and top up to the right torch height. This was for the A81. You can easly adjust for a S45 and WG80. Whatever you have.
Attachment 6607
Original non-cad paper plan and before drilling for the torch, screws to keep locked, the wing/nut holds it and it does not slide in and out, clockwise or counter. The HF wing nut broke, so the cool factor went away. Through them all on the trash after a second one was so brittle and broke (no joke).
Attachment 6608
A81 set at a random spot and I spun it over and over. Standoff is good. Never came lose. Made a video, but never put one on here before and not a youtube or spacebook fan myself. You have to trust me, I was surprised it did not move.
Attachment 6609
Cranked it all the way in to the magnet base, just a tad over 1.5" center to torch center. So, 3"+ holes only due to the magnet size.
Attachment 6610
Summary:
If you want a nice one, plasmahelper.com has a really nice one you can flip and I believe get under 3".
This was my son and I messing around. I will take some picture when we use it and confirm it worked OK (not tomorrow, we are backed up from screwing off on this project today :) ).
I spun it over and not and it never moved. The nozzle is far from the cutter board material so it should not melt. The heat might degauss the magnet, but it is a pretty strong magnet for $2.99.
