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MM Vintage drive rolls are slipping

sideStori3s

New member
Joined
Sep 14, 2025
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4
I am having a problem with my MM Vintage welder and I have no idea how to fix it. The drive rolls spin fine when I pull the trigger but the wire slips. I have tried everything I can think of. I put in a new liner and a new gun. I adjusted the tracking screw to make sure the rolls are lined up. I have even tried different drive rolls and different kinds of wire. The tension adjustment that clamps the roll is as tight as it will go. But I can still stop the wire from feeding just by grabbing it with my hand while the rolls keep spinning.

What else could be wrong with it? Any suggestions will help!
 
I am having a problem with my MM Vintage welder and I have no idea how to fix it. The drive rolls spin fine when I pull the trigger but the wire slips. I have tried everything I can think of. I put in a new liner and a new gun. I adjusted the tracking screw to make sure the rolls are lined up. I have even tried different drive rolls and different kinds of wire. The tension adjustment that clamps the roll is as tight as it will go. But I can still stop the wire from feeding just by grabbing it with my hand while the rolls keep spinning.

What else could be wrong with it? Any suggestions will help!
looks like the issue is with the tension mechanism itself, not the settings.
The culprit is the tension spring on the drive roll arm.
After all these years, it's probably lost its strength and isn't applying enough clamping force. You'll need to replace it or find a way to add more pressure
 
You didn’t mention what size wire you are using. Different wire sizes require different rollers. Flux core also uses a different roller because it is harder than solid wite
 
Take a close look at the drive roll tension arm and spring because they can weaken over time or get slightly bent, so even at max tension, they’re not clamping hard enough
 
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