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That looks awesome Bart.

Maybe I missed it but what accuracy are you getting from that setup?

I have not really measured all the parameters yet. The basic machine is pretty accurate. If I cut a square, the sides are parallel and of equal length within a few thou. I return exactly where I started on complex shapes like the PS:One snowflakes, so I feel good about backlash.

I have been playing with voltage, current, and speed a lot so I have not been worried about the kerf yet. Once I settle on those values I will try to see how consistent that is. Trying to cut an exact 2" diameter circle probably needs a consistent kerf more than anything else.

The electronics are finalized now and I am finalizing the frame changes that includes adding the water through. Cutting steel makes quit a mess. It makes a nasty black dust on the floor.

I completed my water trough. This should make things less messy and less smoky.

I made it out of AluPanel. I thought it would be a simple way to get a water tight and corrosion resistant part.

I cut out the basic shape with a 3 inch perimeter around it. I then hand routed a V groove down to the far side metal using a 45deg bit. I thought about doing some fancy overlapping corners, but the placement of the V grooves would be very critical and I did not know the bend allowances. I ended up just cutting out the 4 corners. They were already V grooved, so they fit together really well.

I takes quite a bit of muscle to fold the longer edges, but it worked pretty well. A wider angle bit like 60deg will might have made it easier.

I then used clear RTV to seal the corners. I also ran a bead along the inside of the folded corners. The skin is pretty thin there. I did not want a little ding to cause a leak.

What I've done in the past is to take a 45° bit and grind the tip down a bit. I try to go for a .125" flat on the tip. That's working with 3mm Dibond which I think is about the same thing as the AluPanel. The bit will remove a little more material and allow the aluminum to flex a bit. Even long folds are pretty easy this way. You could also cut a corner reinforcement that way and stick it in with some VHB tape after you seal with RTV, I'm not sure how much stress the water will put on those seams.

A water trough itself will do almost nothing for the smoke. What does work great is having the work sit right at or just below the surface of the water, normally known as a water table. This does a pretty good number on the smoke and noise. And no, the torch wont care if the end is in water. In fact my plasma cutter has an option for using water to replace the shield gas.

The spray of sparks seems to emit a lot of the smoke. Extinguishing them as soon as possible appears to reduce the smoke in my case. I am seeing less smoke than before. The mess on the floor is gone, but the water is looking pretty nasty already.

on the subject of the water tray "looking pretty nasty already" would a type sluce box work , an angled tray with a removable catch tank at one side with recycled pumped water for flow over tray push the particles into the catch tank.

i think i'm over complicating it for small scale but maybe for larger

Bart - Is it possible to get an update on the Plasma Cutter. And may be some more pictures. I just can't wait to start building one of these.


Bob Teeter

There are chemicals meant to be put in the water trough for a plasma cutter to keep things "fresh". Sorry I don't know any brand names offhand, but I have read about them before.

Did this project/discussion continue anywhere? I can't seem to locate it if it did - but it's a Monday and I haven't had my coffee yet so maybe I'm missing something obvious...!?