I've got a Millermatic 211 and I can no longer get the nozzle to unscrew. It just spins without coming off. I got it off when the machine was new, but it's not coming off now. It is threaded from what I recall.

Any ideas? I can spin it by hand or with the large, serrated jaws on my welding pliers, but it still won't come off. It isn't loose; it does take some effort to spin. The tip is not rotating with it.

If you’re talking about the gas shield, it just pulls off. No threads. The tip is threaded, though.

quote:

Originally posted by sigcrazy7:
If you’re talking about the gas shield, it just pulls off. No threads. The tip is threaded, though.

This is my experience as well; should just pull off.

Not this one; it's threaded:

https://www.amazon.com/Miller-...d_i=B09LD75593&psc=1

I tended to call it the gas shield, also. Miller calls them nozzles for some reason. When using the pliers, I'm pulling pretty firmly while rotating. Nothing.

Below is a pretty good diagram of the MDX series MIG gun that I have; I've added notes in red/green. I wonder if the brass insert with the female threads has become detached from the copper nozzle. That would explain why it is spinning without coming off. It doesn't really show how it attaches through the white insulation layer, though I'm betting the recessed ring around the threads is where they crimped on the copper nozzle (you can see the crimp marks in my photo). If that crimp failed, then it wouldn't be able to spin the threaded brass insert.



I could try to remove enough material in the mill to split the nozzle off (just like a pinned muzzle device), but I'd rather try less invasive methods first.

I've also sent an inquiry to Miller.

I suspect your theory is right and you’ll have to split it to get it off.
Maybe a cutoff wheel or Dremmel tool wheel with care to not go too deep.

I'm leaning towards that failure theory, also.

I'll wait to see what Miller has to say before doing anything drastic.

I have that same unit. My spool gun is threaded if I remember correctly, but the picture you posted looks like the mig gun that comes with the unit. If that's the case, it is not threaded. just twist & pull. It's held on by friction.

Whatever type this one is. But that picture sure looks like this inner part is threaded on but the shield just slipped on.

Use the welder, it will likely come off when it is hot.

The video clearly shows that part being unscrewed. I’d grab it firmly with a big channel locks or vise grips where the crimp is and try unscrewing it. Or cut the copper and plastic off and grab the brass with a big channel locks or vise grips and try unscrewing it.

Section 6-6 of the manual for that welder shows the tip pulls off, and the internals thread.

Link to PDF

The manual just shows to remove it with an arrow, but doesn't address threaded vs slip on. They show the tip removal to be the same, and it is 100% threaded, too. The factory packaging of new tips say "threaded" in the name. The video also shows the nozzle being unscrewed first at 21 seconds in.

It's threaded on, guys.

So...I got a "response" from Miller. This was it; I'm not kidding or summarizing:

quote:

You might have to replace the entire neck of the gun unless you can get the diffuser off with the nozzle then you will just have to replace the diffuser and nozzle.

Needless to say, I was pretty pissed at this bullshit, lackluster response. No technical detail, no possible cause, no specific guidance, nothing. I had much higher hopes for this brand. I also let them know all of this in a response email. I emphasized that I wasn't looking for a handout, just some technical help and customer service, of which I received neither. Except for this issue, the machine has functioned very well, but I likely won't be dropping any more money their way.

Looks like nozzle surgery is ON.

FIXED

The crimp had failed.