Weird grounding issue

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I have a MM 211 running on 240 plug.  .30 wire 75/25 gas.  Not sure how much of that info is relevant.About a month ago I was welding and heard a small pop and the wire quit feeding.  It turns out what happened was somehow the wire welded itself to the liner right where the wire leaves the drive rollers and enters the liner going up towards the gun.  I brought my liner to the LWS and they said they had never seen that before.  In order to fix it they cut the back 3 coils off the liner (leaving a larger space between the drive rollers and the liner)  This cut off the welded portion and freed the wire.  I went back and reinstalled the liner and gun.  I checked to make sure nothing was inside the case contacting two things that shouldn't be touching.  I didn't see anything.  I blew the case our with compressed air.  By case I am referring to the inside where the wire etc is housed.  I do not store wrenches or nozzle spray or anything foreign inside the case.So what is causing this and what is the fix?(FYI I now know why everyone should own two welders, because if one craps on you at least you can finish your project)
Reply:No one?So is this one of those mysteries of the universe that no one can answer?
Reply:The liner has the welding voltage on it, if the feed rollers or the reel of wire gets grounded, it will do things like that.
Reply:Originally Posted by BlueweldersThe liner has the welding voltage on it, if the feed rollers or the reel of wire gets grounded, it will do things like that.
Reply:How would it do that ?The feed wheels are insulated from the ground, the roll of wire is insulated from the ground,The power goes to the work because the tip is hot and the work is grounded.simple
Reply:So i made sure the feed rollers aren't touching the liner and that the roll of wire isn't either.  What should I be looking for?
Reply:Wire from the roll of wire touching the case,slivers of metal shavings between the dive rollers and the case. And make sure the gun connector is well seated in its socket.
Reply:Originally Posted by BlueweldersHow would it do that ?The feed wheels are insulated from the ground, the roll of wire is insulated from the ground,The power goes to the work because the tip is hot and the work is grounded.simple
Reply:Originally Posted by danmcphSo i made sure the feed rollers aren't touching the liner and that the roll of wire isn't either.  What should I be looking for?
Reply:By copper stranded welding cable to a lug that makes the neck,liner and tip hot.So to make sure the current only exits the tip, the rollers and spool of wire is floating on insulators.
Reply:The wire was not bunched up between the driver rollers and the gun.
Reply:I re-read you original post. I can say that I have only heard of that happening one other time. The liner was replaced, in that case, and it never happened again.If it keeps happening I would have a tech look at it.