Sieg KX1 & Mach3 won't come out of emergency reset

[Jess]

The estop and the spindle power are of course on separate cables but they run together from the head into guts of the machine. I could be wrong but I don't think either cable is shielded. But surely that would be a major design flaw... and they must have made thousands of these machines?!

That they're next to each other is suspicious. Shielded wires should be fairly obvious - they'd look like little coax cables, and there'd be a screen connected to the ground point.

Regarding it being a design flaw, it's likely an issue of margins and tolerances. Of course, the design should take account of that! There doesn't seem to be a slew of complaints, so, presumably, other Seig KX1s don't have this problem. (Cold comfort I know when your machine is the one that's faulty.)

Now, whilst I love to see the forum fix this, it does strike me that Arc should be the ones fixing this at their expense (or replacing it or refunding your money). Your contract is for a working mill, so they're legally obligated to supply said working mill or otherwise 'make you whole'.

The next thing I'd do is try to come up with a scenario that reliably causes the problem. I know the last thing you want to see right now is probably for your machine to go into e-stop, but this will at least allow you to tell if you've fixed it - or at least if you're seeing an improvement. (Alternatively, if you are putting the problem onto Arc, then you can show them that it doesn't work and easily test if they've fixed it.)

I'd avoid making major changes to the wiring right now, at least if you're hoping Arc might provide some remedy. Whilst JAZZCNC's wiring suggestions - star ground, separating cables etc., - are perfectly good, once you start cutting cable ties and rewiring things you're modifying the machine.