lincoln pro mig trouble shooting help

[msc66]

Hey guys, I have a lincoln pro mig 135 that I bought at Lowes. Its about 4 or 5 years old and lately I've been having trouble with it. I either get a lot of spatter or what seems like a weak burn with just a hum and the wire just seems to melt and drip off without burning into the metal. When I can get a bead run like I said, there is a lot of spatter and the welds are really dirty and smokey.

I changed the tip and have a new tank of gas. I can hear the gas coming out when I pull the trigger so I don't know. I'm in the middle of a project and have a week to finish so any help would be great.

[67prostreet]

Re: lincoln pro mig trouble shooting help

Sound like you might have moisture on the wire or in the feed line. ???
Also, your not trying to use flux core with gas are you?

[rightpedal]

Re: lincoln pro mig trouble shooting help

Flux core was what I was thinking also. Check your ground connection in the machine and at the clamp(wire to clamp bolt). Does it happen at all settings?

Steve

[fabricatordave]

Re: lincoln pro mig trouble shooting help

flux and gas use different polarity also read the inside of the lid

[msc66]

Re: lincoln pro mig trouble shooting help

No flux core wire. I'm using the same mig wire as when it was working right. It was the same session. It was working fine then it gradually started screwing up and getting worse.

[dieselgeek]

Re: lincoln pro mig trouble shooting help

makes me think there's a weak connection somewhere. Mine did this when the ground connection was coming loose...

[Huskinhano]

Re: lincoln pro mig trouble shooting help

Not a real expert here but a couple of thoughts since I have a MIG also. I'm assuming it's a 120 volt welder since it's a 135 amps. Nothing really wrong with a 120 volt welder but you need to really make sure you're using a really good circuit. I'd say make sure the circuit you're using is at least 12 gauge wire (mine is #10) and really short. It's doesn't take a long run to start to have voltage drop and make for difficult welding. Next, how are you using the gun? You need to make sure you don't have any breezes to blow away the gas and you need to drag the gun, not push it when welding. This is to make sure the gas is covering the molten metal. I've forgotten to turn on the gas a few times and you'll really get some lousy welds!. There's a thought, check your regulator. I was also going to say check polarity but some one mentioned it. Usually you want the gun to be - and the work piece to be + but do try swapping to see how it works. BTW, this is called straight polarity.


I'm thinking you probably are having issues with the circuit having voltage drop.

[msc66]

Re: lincoln pro mig trouble shooting help

Well, I think it was the wire. There was still a good bit on the spool but it wasn't spooling off smoothly and the wire was kinked up in places. Bought a new spool of wire and it seems better. Who'da thought.

[KeithTurk]

Re: lincoln pro mig trouble shooting help

Mike I was going to say Wire.... also do yourself a favor even though you have the new wire in already.... roll it backwards and look at the inlet of the feed cone on the gun side of the feed wheel... I've had it get goobered up with junk... especially if your junk sits around rusting waiting on your nappy butt to get back to it...

usually cleaning the guides and getting back to good wire on the roll will sort that problem out... ( one layer around )

K

[rightpedal]

Re: lincoln pro mig trouble shooting help

Cool to hear your problem has cleared up. I don't mean to beat a dead horse but.... still check that ground wire. I have had the problem with more than one Lincon. ( I have an older sp125 plus and love it)

Steve

[CaminoKid]

Re: lincoln pro mig trouble shooting help

As with all electronics,the biggest key to success is GROUND.

[Ron Ward]

Re: lincoln pro mig trouble shooting help

For future use, try some of these:



These are wire scrubbers. They simply clip on to the wire between the spool and the feed rollers. All you have to do is douse them with some wire cleaning fluid (available from any welding supplier) and snap them on. They scrub the dirt, dust and grime off the wire prior to it going through the liner and into the gun. This prolongs liner life and allows the wire to slip through the liner with ease. Put one of these scrubbers on each time you change your wire.

Ron

[Smack]

Re: lincoln pro mig trouble shooting help

I was about to suggest the wire scrubbers also, they will help keep the trash out of the liner. Anything that will get in the liner will cause the wire to drag, and then the feed rollers will start slipping, creating shavings that will also get into the liner.

I have had lots of problems with cheap wire once it gets toward the middle to end of the spool. I finally just went back to using the smaller 2 pound spools again. They dont last as long, but they dont seem to start hanging up or corroding as fast as the large spools. I dont do anywhere near as much welding as I used to anyway, so the smaller rolls are better for me anyway, as they don't have to sit around as long between use.

[msc66]

Re: lincoln pro mig trouble shooting help

Thanks for the tip on the wire scrubbers and I did check the ground.
How do you know when the liner needs changed?

[Ron Ward]

Re: lincoln pro mig trouble shooting help

Thanks for the tip on the wire scrubbers and I did check the ground.
How do you know when the liner needs changed?

You should be able to push/pull the wire through the liner with your bare fingers. If you have to grasp it with a pair of pliers to push/pull it through the liner, it is dragging too much. To test this, release the tension on the drive rollers and snip the wire close to the spool. When you do this, make sure you have ahold of the spool end of the wire so it doesn't uncoil like a big spring! ;D Wrap the loose end of the spool so it doesn't get away from you and then you can check the resistance through the liner with the wire remaining inside the liner. Liners are expensive, so anything you can do to extend their life (don't kink the gun lead and keep the wire clean) will help save money in the long run.

Ron