Hobart 210 mvp wire feed problem

[Professor Marvel]

I have a Hobart 210 mvp and am having a wire feed problem. Using hardface .045 flux core. Using the larger groove on a 035/045 roller. Using plastic tip cover.
Feeds and welds fine for a while then it stops. Looks like the wire feeds then roller spins without moving wire. Then feeds more until it stops completely. At this point I take the tip off and wire is jammed in it. Pulling from either side leaves a piece stuck and I have to put in a new tip and cut and restart wire and it works for a while.
I think when the wire first spins without moving wire it flattens wire a litttle then it drags the flat spot to the tip then jams hard in the tip. NOT SURE.
If I am correct, what am I doing to stop/jam the wire feed long enough to start the wire flattening?
Any other ideas. My speculation could be inaccurate. I have not welded much. Could I be distorting the tip so it starts to jam? Never had this problem with .035 non hardface wire.

 

[Shield Arc]

Couple things I would do.
Take the gun off the feeder, remove the contact tip. Place the end of the gun that goes in the feeder, on the valve of your oxygen bottle, and blow out the liner.

Take an oxygen & acetylene tip cleaner, and open up your contact tip a few thousands of an inch.

With any kind of flux core I use serrated drive rolls.

 

[Professor Marvel]

Thanks
I tried to drill a tip out but just broke the drill and got it stuck in the tip. Another tip gone. I like your tip cleaner idea. I was certain that I was using a knurled groove but now I have to check in case I was wrong. That would be a good reason for my problem wouldn't it? If it is smooth where would I get a serrated one? Are the different brand rollers or at least some of them interchangeable?

 

[Shield Arc]

Using V-groove drive rolls on flux core wire will deform the wire.
I've had good luck ordering drive rolls from this outfit.
https://weldingsupply.com/cgi-bin/browsecatalogs.pl?UNDEF::

 

[Professor Marvel]

Thanks again SA. Do I need a Hobart roller or will a Miller or lincoln interchange with it?

 

[Shield Arc]

I really don't know. Maybe certain Miller drive rolls will work on a Hobart welder. Miller and Hobart are owned by ITW, so it's possible. I'd be surprised if Lincoln drive rolls would fit a Hobart welder.

 

[Professor Marvel]

Thanks
Looks like mine is knurled after all. I will try making the hole in the tip bigger. The tip cleaner sounds like a good idea to me. I thought maybe I could find .050 tips but I don' see any.

 

[Shield Arc]

Sometimes when running aluminum wire, when the wire gets hot it expands, and jams in the contact tip. Some manufactures offer over sized tips. Sometimes you just have to file the contact tips open just a touch.

 

[TomNOh]

Make sure the grooves in the 2 rollers are aligned with each other. There is a screw deep inside the center of the roller holder that will adjust it in or out to align with the other one. Check your manual for adjustment procedure.