Mig welding problem

[handirifle]

I have a little Campbell Hausfeld 110v mig, that HAS been working fine. Makes noce welds, when the nut holding the gun does his part.

The problem came this morning. I was welding some vertical struts for my utility trailer, I am building. The first one seemed fine, but I noticed it didn't seem quite as easy to get a good bead, when using gas shielded wire.

Then it got to the point where all it did was pop pop pop, and splatter weld. I traced it to a poor ground, fixed that and the same thing. ???? OK did some troubleshooting and found the ground cable has loosened at the clamp. Another repair. I also checked and tightened the other end of the ground cable as well. Now I notice the cheapie spring regulator that came with it, is leaking when the gun's not being used. A little push on the plunger that sticks out and it stops, but KEEPS coming back.

I took it apart and cleaned, and reassembled it. It no longer leaks (figured it had some dirt in it from using a neighbors tank for a bit) BUT it seems like more than usual gas is coming out, and still unable to hold a steady arc.

I switched the ground clamp to other spots, and no real improvement. Then I switched the polarity of the leads, and put the flux core wire in to test. Perfect, beads (for me anyway) and constant sizzle at the weld.

Could the regulator cause the popping and inability to hold an arc? I have been getting very good welds prior to this.

I am heading out in the AM to get a REAL regulator, so I hope that is the problem. If you guys don't think it is, I'll try to take the welder back to HD. But I head out early, so would appreciate any info I can get tonight.

Thanks

 

[Transit]

What turns on the gas flow, a solenoid or a valve built in to the gun. Is the defuser in the gun clean? do you hear gas flow at the gun tip?

 

[jayste]

What Transit said and also clean metal? Another thing to check is to insure that your wire is running freely at the spool. I.E.- does the spool turn freely. Regulator is an important issue as well due to the obvious gas leak and that welding gas isn't cheap.

Also, good tip? Good liner in gun/lead?

 

[slowzuki]

Sounds like a problem in the gas delivery and that regulator would be suspect #1.

 

[handirifle]

Sounds like a problem in the gas delivery and that regulator would be suspect #1.

Crap. Wrote out a big long response, and THOUGHT I posted it last nite. Bummer.

Problem fixed. I went to the local Airgas (30 miles away) store and discussed it with them, no doubt the regulator. Got a new, 2 guage unit and it flows so much better, and makin bacon again.

To answer the above questions, metal perfectly clean, good ground connections all around, I could hear gas at the tip, but must not have been enough. It works of a solenoid in the unit, and wire feeds as smooth as it ever has.

The new regulator flows gas so much more consistently, I can even hear the difference. It seems to flow more than it ever did before. I am running it at 20psi, that's what the guy recommended, otherwise I have no clue on that.

I do notice a different issue now though. I was welding 3/16 angle, about the limit for my little machine (85 amps at peak) and with it set on high, wire speed about 2.4-2.5, it seems to melt the wire almost before it meets the iron. Wire speed too slow?

 

[Transit]

now that you have fixed the gas flow problem, you may need to relearn. It sounds as if the wire feed is too slow. 0.024 or 0.030 wire?
The gas rate can be in the range of 15-20 CUFT. Why wast gas.

 

[handirifle]

now that you have fixed the gas flow problem, you may need to relearn. It sounds as if the wire feed is too slow. 0.024 or 0.030 wire?
The gas rate can be in the range of 15-20 CUFT. Why wast gas.

Appreciate that bit of info, I was hoping so. Wire is .030.

 

[slowzuki]

On high amps you need pretty darned high wire speeds, on my unit, at about 60 amps welding 1/8, with 0.023 wire, my wire speed is about 6 out of 10. If I don't get an arc start its got 4" of wire out before I can react to stop. 0.030 wire slows it down a bit but burn back means to low of speed.

 

[Transit]

You can get scientific about it.
The rule of thumb is 1 amp for each 0.001 inch of stock thickness.

1/16 inch stock is 0.0625 inches needing 62.5 amps.

For 0.025 wire the multiplier is 3.5.

3.5 x 62.5 = 218.75 in/min or 21.8 inches in 6 seconds. That will give you a good starting point to tune from.

0.030 wire is 2 and 0.035 wire is 1.6.

 

[handirifle]

I know there's more to welding than I will ever come close to knowing, so I appreciate all the input I get.