I am welding 22guage with .023 wire in a full size ESAB Migmaster 250 and on the Lowest Voltage I am still getting the bead showing up on the back. I am not burning through but I am geting like %110 penitration. Should I up my wire speed and just grind more when I am done? I have tried going faster and increasing my stick out but it (the bead) still shows through on the other side.

I can't wait for my 110V little Lincoln to get here!

You can up the resistance by increasing the length of the wire at the tip while welding. You can also use a spot welding technique in which you alternately squeeze and release the trigger while welding. Basically, you're tying a string of spot welds together instead of running a continuous bead.

Zach, you want some visible penetration from the backside.

If you take an ICAR welding certification test you HAVE to achieve certain measurements to pass the welding test. On the backside of the weld you cant exceed more then 5mm or 3/16 width of peneration. The height of peneration cant exceed 3mm or 1/16, but you NEED some peneration. If you cant feel the backside peneration you FAIL the test.

Every single type of welding when using a MIG needs to have some visible backside peneration.

The guy that tought me how to weld always said welding is very much like making love. "Without peneration you aint got nothing."

It's actually more expensive to buy natural foods graemlins/thumbsup.gif

Thanks guys that really helps 70! I got the Lincoln SP135 PLUS today so I am getting ready to lay some test beads with it(the boss will be happy to get his monster mig back). Ofcoarse being a maintenance weldor I am used to looking for some penitration but not much (on 1/4" angle iron!)

Interestingly enough the little Lincoln says to reverse the polarity on 24 guage to reduce chance of burn through. THAT is something I never though of, I thought you only DCEN the flux core wire. It also says to run flux core on the heavy (for this sheet metal welder) 3/16" frame rails and stuff. Why can't I run .035 solid with gas instead?

Eric what kind of wire to you run? Good old mild steel .023 or some kind of fancy "easygrind"?

Zach, I use nothing but .023 wire. Anything more then that is just a waste of time. Takes more heat to melt that thicker wire, that equal more warpage in the metal.

On sheetmetal I dont understand why anyone would use flux core wire. Its dirty, you got to clean it everytime harder to weld.

Ive never tried any of these new easy grind wire alloy. I use good ole er-70-s6. I normally get K-T brand of wire as that is what the store sells. But once this sppol runs dries am getting some wire made by Miller called Gold seal I believe. Welds nicer then the stuff I have now. Also noticed that the MAC tool guy sells the Miller brand but is just relabeled half arsed

one thing might be to use a good heat sink near by to pull some of that heat away from the sheet metal? lay copper bars next to where you are welding or wet rags? just a thought.

OK that's it I will get some .023 the Lincoln came with some .025 that I will burn up on tests. The 023 wire is more expensive but it makes sense you would need less heat to weld the smaller wire. The Easygrind is like $6 a LB in 10LB roll and the 030 Easygrind is $3 a LB so I may just go with the good ol $1 a LB .023 wire, IF you passed Icar with it that is good enough for me ;)