Bad mig welds

[dirt clod]

I have a Lincoln Electric Pro MIG 180. The 1st few times I used it I was amazed at the nice welders. I was making much nicer welds than I could on the miller at work. All of a sudenly I can't weld for nothing. I'm still on my 1st spool of wire and tank of gas. The welds have a lot of pores and don't seem to want to penetrate. There is a lot of spatter. Some of it reminds me of cutting torch slag! It looks burned. I tryed it on several pieces of metal. All come out like I was welding dirty metal but it was not. I really can't think of anything that would have changed. Any ideas????????

[aspenelm]

out of shielding gas?

[Inspector507]

How old is the wire? Exposed to dampness? Is there any film on it?

[dirt clod]

Not out of gas. I got a 320 cf tank. Still have part of my "starter" 2# roll. All of it is less than a month old. We have had some rain. I built a large offroad cart for it so it has not been at ground level or setting on a concrete slab. Wouldn't think damp air would ruin the mig wire this soon as my 120v fluxcore welder sets much more than this. I can hear the gas coming out. It acts like I'm not getting any though. Maybe gun needs cleaned? Maybe sucking air into the gas stream somehow?

[dirt clod]

" film on wire" not sure what your asking.
I looked at the wire. Didnt notice anything strange. But then again I always say I have a welder and that I weld but am not a weldor. Sometimes I could be more refered to as grindor Wife asked me one day why I was putting that stuff on if I was just going to grind it back off, It made no sense to her

[schmism]

pics might help track down the problem.

[oldhippy]

I have had welders for a couple of years and on the migs the tips can be worn inside and need to be replaced from time to time. I keep tips on hand all the time ( they are cheap for mine about a dollar) replace the tip and see if this cures your problem. I am talking about the bronze fitting that the welding wire comes out of. The life of the tips depends on keeping splater from sticking on them. I keep a jar of tip jelly next to where I am welding and dip end of gun in it quite often. This is the first place that I would check if not repost and we will see if we can get you back to making things. This is the fun of welding. big dan

[digger2]

See if your nozzle is clogged with spatter back where the gas enters inside the nozzle.You'll have to unscrew your nozzle to check this.Also check all your gas line connections.Even though your gas line is pressurized,it can still suck air,contaminating the gas mixture.
Might want to check the hoses for cracks or cuts also.....digger2

[bucmeister]

I release the pressure on the pinch roller, turn off the tank valve, the pull the trigger to release all of the pressure in the gas system at the end of each session. Have found that I have to reverse the process when first starting up to get the gas back in proper concentration in the entire hose. Thought I had once, but figured out it apparently takes longer than I thought to get the gas in full concentration because one time I welded a short bit after a short purge and the weld looked really poor and porous like you describe.

[Scooby074]

It sounds like a shielding gas issue.

Like the others have said check the mig nozzle for any blockages. Also check the small diffuser holes in the gun and make sure they are cleaned out.

You say you can hear the gas, but what CFH are you running on the regulator? Try increasing the pressure to 15-20 CFH if its not there already.

Is the metal that your welding GROUND clean? Check your gun polarity. You'll want DCEP (Reverse) polarity for gas.

Make sure there are no drafts and that you are keeping your gun nozzle within 1/2" of the surface being welded.

Check your gun lead and hose from the regulator to make sure it hasn't been crushed and is restricting your flow to the gun. Also check where the hose goes into your gas solenoid on your machine. There is usually a fine filter in there. I was having poriosity problems with my new machine, turned out that filter was partially plugged with pipe dope.