I developed the same problem with my Millermatic 252. I bought the machine thinking I could weld just about anything I ever wanted to weld and for awhile it did. I noticed from the start that when I did small jobs it welded like a dream. But then while I was welding two large I-beams together to go into my shop for an overhead rail for a 1 ton chain fall I found that the more I welded the more hang ups I would have. Backlashes, wire burning up into the tip and just basically all around crappy welds.
I asked everyone I knew what could be wrong and all I got was change the tip, change the liner, welding with the wrong settings, the welder doesn't know what he's doing. I got that last one over on the Miller site from a couple of the know it all's over there. It was so frustrating....I mean to spend all that money for more machine that I thought I would ever need and then have problems like that was heart breaking.
I had an older Miller transformer machine that I welded with for years and in all that time I don't think I ever replaced the liner in it and to burn up a tip was a very rare thing and I welded with it for days and it never missed a beat. The reason I mention this is that it had the very same torch on it that was supposed to be on this new machine so when I bought it I didn't see the need to upgrade it to something larger.
Well, the M 25 torches today are not the same torches that were on the older machines. I guess to stay competitive Miller did what everyone else does and gets cheap on stuff where ever they can to keep their prices down. It's like buying a bag of potato chips......you used to get a a smaller bag but it was full of chips for like .20 cents. Now you get a great big ol bag with nothing but air in it for a buck forty nine.
Anyway, after being called too dumb to even own a welder by the welding legions over on the miller site, replacing drive rollers several times, replacing liner after liner, after burning up hundreds of tips, throwing away several rolls of wire thinking it was rolled wrong, I even took it to one of millers repair centers where it stayed for 2 long months and all I got was a new liner...(even after I had already told them it was a new one in the torch that had never had an inch of wire run through it) and a $250 bill even through it was still under warranty, I finally realized that the m-25 torch was just not the same as the torch on my older machine.
What was happening was.....and this is my own judgment on this, was that after you weld for awhile especially if you are welding long runs the whole assembly heats up and especially where the light weight aluminum angled piece at the end is. Where the aluminum and the copper pieces connect at the tip it gets so hot that it actually caused the steel liner that the wire runs through to expand enough that it will twist or unwind causing the hole in the liner to become smaller which pinches the wire and well you know what happens next. You can replace all the pieces at the end of the torch and weld for awhile but if you are welding long and hard you will end up upgrading to a heavier torch if you ever want to get anything done. I might say that I came to this conclusion on my own because no one over at Miller or the miller forum will admit it and still want to blame it on the operator.
Let me say this......I am not bashing Miller.....well maybe a little but I love my 252 I just wish when I bought the machine they had told me to upgrade the torch if I really wanted to use it.:laughing:
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