Which gun do I have?

[Eyecatcher]

Recently got my hands on an older Airco Dipac 200 mig welder. It came with a Tweco gun. Everything works great except I think I need a new liner, can't get the wire to feed smoothly. Can't find a model number on the gun, but on the connector at the welder, it has Tweco X215-07110-156. I think this is a #2 Tweco but not sure. anybody know?

 

[Shield Arc]

Have you tried blowing the liner out yet? I like to remove the gun from the feeder, remove the contact tip, and hold the end that goes into the feeder up to a oxygen bottle without the gauge on, and crack the oxygen bottle valve.

Here is a Tweco model 2 gun on the left, and a Profax 400-amp gun, which is a Tweco knock off, but pretty much the same thing as a Tweco model 4.

 

[Eyecatcher]

My tweco gun must be much older, it looks nothing like that one.

 

[Shield Arc]

Really? That's strange, I've been using Tweco guns since the 70s, I don't think they have changed much.
Can you post a picture?

 

[weldermike]

Have you checked your spool for any snags in it? Just a possibility.

 

[yomax4]

One of the guns is a private lable #2 Tweco Gun for IWDC. Takes a 42 series liner the other is a Profax copy of a #4 that uses a 44 series liner. The 42 series part number is 1420-1123 ( .045 ) the 44 is 1440-1103
( .045 ). Give this info to your distributor and tell him you have a #2 and or #4 gun or buy on line. Always buy a size large liner than the wire size you run.

 

[Eyecatcher]

Thanks for the info, I'll post a pix today. I'm going to try blowing out the liner as suggested. The spool looks good. There is some discoloration on the wire, I had to strip off quite a litle that was rusty. Liners are tremendously cheaper on line than at the welding supply, if I can figure out which one.

 

[Ed of all trades]

I would spray down the liner with brake clean and then blow them out it seems to work better.

 

[Eyecatcher]

Shield Arc - I was wrong mine looks exactly like the #2 tweco, ixcept is doesn't have the logo like that, simply Tweco molded into it. I just tried to blow air through the liner - nothing at 150 psi. If I keep the lead straight, it feeds pretty good, if I bend it the slightest, the wire feeds in sputs, so I'm sure the liner is bad. What do you think of the pads that ride on the wire. I've heard both sides of the story. Maybe 2? one dry and one with a little oil on it? Seems to me like a litle lube would help the wire feed, or would it just muck up the liner?

 

[Shield Arc]

Yeah, sounds like your liner is bad, time for a new one!
Personally I don't believe in the pads, especially the ones with lube on them. There was a big blow out a couple years ago on the Miller site about this very subject. One of the Miller mods joined in, and said not to use the pads with lube on them. If you do use a pad, just use an old ear plug, with a small clamp, why buy a fancy pad? Even when working all I ever ran was Innershield, that stuff has a caked on graphite lube, then with the serrated drive rolls you have wire shavings stuck in this graphite lube, I still didn't use the pads, just blew the gun out every Friday night at pickup time.