MM211 needs a new gun

@Metalshop

Awhile back I noted that the mig welder did not seem to be getting enough shielding gas to the tip, leading to terrible porosity. A bit later somebody told me it was fixed. Last night while fixing the mower I noted that it was indeed not fixed. Setting the flow to 30 plus cfh still yielded terrible porosity. So tonight I took the gun apart and found that the line feeding shielding gas to the torch had separated from the torch. I was able to push it back together and with liberal use of electrical tape I believe it will stay in the gun where it belongs for a little while. However, I do believe it is only a temporary fix and will eventually begin leaking there again. The new mig gun from Miller is the m100. We should be thinking about replacing the old one as soon as possible so that this does not fail again and begin to affect people’s work.

Link to (Miller) replacement:

Link to alternate (yeswelder) replacement:
https://a.co/d/hyadDg5
I cannot vouch for the quality of yeswelder parts but they appear to have decent machines and service based on comments on the web.

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Can the liner be swapped out? They’re usually replaceable for ~$20

It’s not the liner. Yes we could swap it out, but the gun would still be broken.

Oh my bad just going off the liner in the picture. I’ve never blown a gas line, but I sure have destroyed a few liners. :joy:
Did it blow from the pressure being too high at some point with a clogged tip?

It honestly looks to me like the gun was pulled on. If the copper braid in that picture is pulled straight the gas line is about 1 in too short.

A non part specific Google searches shows those gas lines in the $10-20 range. I can’t remember ever replacing one so idk but it seems like it would be pretty easy. Just small talking/brainstorming.

I had a welding gun at one point that had a flexible neck. It was great for odd angles. If the gun does need replaced, maybe an “upgrade” of something like that would be possible. I think it was called a swan.

I’m not sure where you are finding that. I’ve never known the line to be replaceable

Best price I can find for a Miller 211 100A replacement gun: MILLERMATIC 130,140,141,211, Replacement New style MIG GUN MDX10010 100A 10Ft | eBay

Would that work?

The MDX has a different end than the M-series. The newer 211 is different than what we have and I’m not sure if the guns are backward compatible. If you call matheson, they might be able to tell you.

The mm211 is down again until the gun can be replaced. I guess I’m kind of impressed my temporary fix lasted as long as it did, but tbh, I don’t know how long it’s been bad again. Likely a lot of people have been having problems and just didn’t realize why.

If setting the gas flow to “normal” levels isn’t getting the job done, cranking it up as high as it will go isn’t the answer.

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Does anybody know if the gun has been replaced yet?

No it has not.

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I’m assuming that it’s been ordered and we are waiting for it arrive? When is it due in?

Looks like your in a hurry to get it working, it should have been repaired properly a year ago, when someone with the correct authority gives me permission I’ll try to order it. Matheson just told me we wont repair your welders any more, and wont sell u replacement parts to do it yourself either! I said that pretty much puts you out of business don’t it? Oh we can sell you gas or a new welder, we cant take on the liability of working on used equipment !

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I would like to see things that are broken fixed so that the membership can use them and potential new members can be impressed by the availability of tools they might want to use. Yeah, I’m weird like that. I’ll work with leadership to get it resolved.

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MM211 IS ALIVE AND DOING FINE!
IT will work as well as it did when new!
When the new spool of wire runs out ask me before loading new wire thanks!

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First weld no adjustments no porosity, hot!

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