Do you know the amperage of the breaker on that circuit?
Also, has anyone checked the spark gaps?
50 amps I believe. I feel reasonably confident on that. Supposedly it requires 100 for the AC to work well
I’d guess the answer is “no”.
Per the manual:
2 Spark Gap
Normal spark gap is 0.008 in (0.203 mm).
This can be checked, with the input breaker OFF, via an access door and a feeler gauge.
I’d say, yeah, we’re a skosh under-sized on that feeder. 
(edit: Hey, how about we get that converted to a 460v feeder? :-))
Lol. Yeah let’s call Oncor to set a new transformer.
I’m not serious for those who can’t sense my sarcasm.
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Well, they work both ways. Just need a 240v → 460v in the electrical room. 
On a more serious note, here’s a better table of the required circuit amperage:
I’m guessing a 175 ampere circuit to the metal shop is pretty much out of the question, right?
(edit: That 460v transformer for $300 is starting to look like a good idea, eh?)
Hadn’t thought about that, but yes, there is a way to physically limit the current. The foot switch, in TIG mode, is just a rheostat. Lower resistance == more current, or at least that’s what I would expect. Pretty easy to check that. Just add some resistance inside the Miller box which can’t be removed and you effectively limit the highest amperage which can be obtained, irrespective of the knob on the front of the box.
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I have been told it was checked, but I was not present for the checking.
How about a “Scald-guard” faucet style fix, wherein we put a limiter on the knob…
Down fall to a transformer like that is you will about double your input current compared to the output. I don’t think we have that much power.
Psssst Oncor giving gods please set us another secondary transformer. Lol.
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So while thinking about the new pump, I realized we did not buy a new coupling for it. Now there may be a chance that they sent a new coupling with it. I can make one to place in there or someone else could 3D print one as the one in it was plastic. Or perhaps we could spend the 6$ to buy one. The ones that I have seen online were brass.
So I may run over to Grainger in downtown Ft Worth to get a coupling.
Just catching up here with the welder and the circuit. I don’t think we can get 480 volt service at our current location. This would require changing the transformer outside the building. I will call Oncor and double check what we can get. A 200 amp circuit for 208V is likely cost prohibitive but if someone wants to get a quote go for it (assuming we have a panel that could even host it because that’s half a panel).
Yeah Luke, it would likely be very cost prohibitive. I’d be willing to bet that it would be in the 10’s of thousands of dollars to do.
I called Oncor. They didn’t know details about our transformer but said they’d have a specialist call me within a few business days with the information on it.
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I’ll be at the space tomorrow for the antenna raising. If you happen to be there, we can take a look.
After a discussion with Lee over the weekend, I rescind my earlier objection to selling the 351 & 250. A couple of nice inverter units (he mentioned Miller Dynasty) funded with the proceeds of these two sales would be great.
We’d still need to up the breakers just a bit to 50A circuits, but this is a better plan than what I originally proposed.
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It’s on the list to get the pump in. Lol. Didn’t get a chance to get to it today.