MM250X problem

[jeepthing07]

I just changed my MM250X over from .035 wire to .023 to weld sheetmetal. I changed the drive rolls, liner, and tips to .023. Sometimes it welds fine, but then it will pop and burn back. and the wire will stick to the tip causeing the wire to start backing up in the drive rolls. Then i have to re feed the gun just to have it happen again. I even tried useing a .035 tip and it still happens. Anyone had this problem?


Even when i ran the .035 wire sometimes it would pop and burn back but the wire was stiff enough to push it out the end of the gun. This thin wire just turns into tangled up ball where it comes out of the drive rolls

[fun4now]

are you using a 11lbs or 8" role ?? i have had bad rools befor that did that they role it so it gets under its self and stops or slows down, my LWS was happy to replace the role and all was good after that. it could be the rool. other thing might be its too tight on the tention on the drive wheels if its dirds nesting insted of slipping. even the .025 should slip rather than biredsnest on ya. if its properly ajusted and you get a burn back to the tip you should be able to just smack the tip on some thing to get it to pop lose and keep welding or in a werst case grab the ball and pull it out a lil bit and then cut and stwrt welding again. nozel gell will help keep it from sticking too bad if it dose burn back, alowing you to just knock it loose and continue.
welcome to the site and good luck.

[JonnyTIG]

Sounds like you may have cut the liner too short. Dont know, just my thoughts

[jeepthing07]

are you using a 11lbs or 8" role ?? i have had bad rools befor that did that they role it so it gets under its self and stops or slows down, my LWS was happy to replace the role and all was good after that. it could be the rool. other thing might be its too tight on the tention on the drive wheels if its dirds nesting insted of slipping. even the .025 should slip rather than biredsnest on ya. if its properly ajusted and you get a burn back to the tip you should be able to just smack the tip on some thing to get it to pop lose and keep welding or in a werst case grab the ball and pull it out a lil bit and then cut and stwrt welding again. nozel gell will help keep it from sticking too bad if it dose burn back, alowing you to just knock it loose and continue.
welcome to the site and good luck.

I am useing a smaller 8" roll, i backed way off on the tension of the spool. although i dont know if it might be a bad spool of wire i will have to look at it closer. I have the drive rolls pretty tight i dont think it could slip at all i will loosen it up and see if that fixes it. I really hope loosening the rolls will fix this problem cause i have some welding to get done for a friend. Thanks!

[fun4now]

this may be info you already know but best to start out with the basics befor worrying about a bigger problem.
the role should be just tight enough that it wont spin on its own sowhen the drive wheels stop pulling the role will stop. the drive wheels should be loose enough to let the wheels slip if the wire stops moveing at the tip. put the tip of the gun to the ground and hit the trigger if the wire bends out and pushes the gun away its too tight loosen it up till it slips insted of bending the wire at the tip if the tip is about 1/2" off the floor. this should be good but might be ok to be just a hare tighter. this will prevent the birds nesting if the tipwelds to the wire. that way if it dose stick to the tip all you have to do is grab your cutters or plyers and pop the wire loose from the tip and keep welding without getting a nesting problem.
hit the triger and watch the wire comming off the role if its getting stuck due to being under the other wraps you got a nessed up spool, first try pulling off about 20ft. or so and then retry to see if its feeding ok again. if its still getting tangled you may need a new rool. if its not sticking too bad you can tighten the drive rools a little bit to help it get past a small snag, but keep in mind if you tighten them too much you will get the nesting problem.
if its baddle tangled your LWS should trade out the role of wire for you.
good luck hope it all works out ok.

[Danny]

The MM 250X has a reputation for having the problem that you are experiencing. Probably a big reason why it had a very short production run.

http://www.millerwelds.com/education...highlight=250X


Personally, I'd just sell the unit,and get something better. The MM 251 with its adjustable Run-in produces perfect arc starts , no matter the wire size -.023 - .035. Plus based on my experience with the MM 250 and what I ve heard about the 250X it has a much nicer arc and weld puddle wet out.

[fun4now]

Danny makes a valid point, the 250X was a step abouve the 250 but still was problematic, the 251 was the solution and has earned an excelent reputation. however replacing the welder may not always be an option, so i would work it out as best as can be and if the above ideas dont help give tec. suport a call

[jeepthing07]

I adjusted the drive rolls so it slips when the wire stops moving. And I have no more problems with the wire bird nesting. It's not worth it to me to get a 251 the 250X was free and I don’t do much welding anymore.

I still have burn back problems but I can live with it. What’s this about the adjustment inside the 250X on a circuit board to adjust burn-in? Are there any write up's on this?

Thanks for the help I appreciate it!

[fun4now]

glad i could be of some help and its working better for you.
looks like the link give the basics and from there maybee a phone call to miller on the internal ajustment.
good luck and happy welding. if ya get another free one send it my way.