Sorry for the lack of pictures, but perhaps a description of the problem would help. I have a brand new MIG machine (FirePower 120 - made by Thermadyne). Here is a picture of the welder so I can explain my settings and the problem that I'm having.



The bottom **** is for AMP/Volts (1 thru 4) settings and the top **** is a potimeter ranging from 1 thru 10.

Now, I only played around for 30 minutes the other night on an old set of stock exhaust manifolds. I was practicing laying a bead down on the heat sheild covering the "pre-cat" in a set stock exhaust manifolds that go on a Ford Duratec V6 ... it's the only scrap metal I have right now. I know for a fact that the manifold & pre-cat casing is SS, not sure about the heat shield shrouding the cat. The wire I'm using is mild steel ... not sure if that makes a difference.

Wire feed is set around 4 on the 1-10 scale and the Volts are set on 3 on the 1-4 scale. I have no problem starting the bead, but shortly after, the filler "pops" and blows out and I must make contact again to restart the process over, I can't seem to keep contact without it "blowing out".

Should I increase the wire feed rate more and just move faster or increase both the wire feed and volts?

The heat shield that I was practicing on was about 1/8" thick ... material unknown. When I turned up the heat (#4 - max volts setting) and kept the wire feed at #4 as well, I managed to blow thru the shield.

Any advice is greatly appreciated!

 

For thinner metals you need to lower the heat (1:lower - 4:highest) setting. Once you establish an arc you can turn the wire feed **** ( the upper one in your case) slowly in a clockwise direction to increase the feed till you hear like an egg frying. That will be the optimum (or near to) setting for that particular metal you are working with. DO NOT<U></U> adjust the heat range (1-4)**** while you are welding. This is a crude but effective way of adjusting your machine.

If you are also welding with flux-core I will suggest that you convert to solid core wire and a mix of 75/25 (Argon/Co2) for a better/cleaner weld and finish.

Check these links out for tips:

http://www.millerwelds.com/edu...tips/

http://www.millerwelds.com/edu....html

Good Luck mang!

 

Thanks for the suggestions & links ... looks like I have a whole lot more reading up to do before attempting again.

For the record, I'm using solid wire with 75/25 mix of Argon/CO2 set at 24 cf(m/h)?. Would too much flow of shielding gas "blow out" the arc? I wouldn't think so, but I'm new to this and have a lot of learning to do.

I was able to get the "frying bacon" sound for a few seconds, then "POP" and a large piece of slag would blow out of the weld and piddle across the garage floor.

 

either your travel is way too fast or your wire feed is too fast. slow down and adjust the wire feed down per spiceisler's advice, but i think he meant turn the feed **** in a counterclockwise direction (less feed) until you hear the sizzling and not popping. set your heat, turn feed **** all the way up, arc (will be popping), and then with your trigger still pulled-work feed **** down till it's sizzling. steady hand and slow travel speeds, have fun.

What's your shielding flow set at?

 

24 cf(m/h) - cfm sounds too high ... pretty sure the gauge says cfh ... see post above yours.

Again, I'm new to welding and simply followed the install instructions on the welder and figured I'd get my hands dirty before asking questions so that I could learn from my mistakes. I have a few books on the subject, but haven't read past the safety/setup instructions.