Help needed on weld quality?.

[Mike65 475]

While doing my sheet metal repairs on my 69 Coupe I have been doing a lot of welding & I converted my Lincoln weld pak 155 220V flux core welder over to MIG gas welder I have the power level down on A which is supposed to be the lowest setting & I get the best weld quality with the wire feed set on 3. Holding the gun almost straight on at the work piece I am welding or at a slight angle sometimes I get great looking welds & sometimes it will blow a hole through the metal. The metal I am welding appears solid new & old & it seems to blow through the old metal, & I am making sure it has a good ground. I am confused as to why this is happening. :confused1: Any ideas or suggestions that could help me out?.

TIA, Mike.

[bomccorkle 12]

I was having the same issue at times. Mine was stemming either from my two pieces of metal not being close enough(1 piece just half as much steel and twice the amperage) or from kinda heat soaking the area and not moving around. You'll notice as you get rolling for extended periods and longer beads you have to speed up a bit as the area has already gotten kinda pre warmed from the heat transfer.

 

Also I think I may do things oddly but I hold the gun in my right hand and angle the tip to the left at a 30-45 degree angle I use my left hand to steady and I push the bead across from right to left. Also I backed off on my wire speed (controls aperage) and I tend to "work" a puddle around in a bit of a circle in structural areas. I also trimmed my nozzle back a bit to be able to get my contact tip closer(remember as the nozzle move to and fro the amperage at the weld changes) and be able to SEE everything. Also a work light does wonders. As you can watch the way your puddle acts you will be better able to react.

Edited May 30, 2013 by bomccorkle
autocorrect......

[RPM 1,190]

+1 on the light. +1 on the little circles with the torch. +1 on making sure the 2 pieces of metal are snug together. The faster the wire feed, the hotter your weld. If you have some scrap metal the same gauge you can practice to get the best settings. Good luck.

 

Bob

[latoracing 256]

I am not shure if you are attempting to run a long bead or not, but here is something that I do. Turn your welder up, to like D, and adjust your wire speed to where you can get it to do a tack weld. Once you have the welder set, "trigger" your welds, as in a whole bunch of tack welds, sort of like having pulse, but manual. You will get all the penitration that is needed to join the metal together, without all the warping, and a little more controll on blowing a bunch of holes. The patch you put on your rocker is a good example, that butt weld going down the rocker. A few tack welds to hold the part in place, start on the inital tacks and continue adding on them. I do this alot, here is an example on my trans tunnel brace

 

 

I was on 4 on voltage, and 50 on wire speed, hot enough to weld 1/4" plate. 100 percent penitration, basicly on the verge of blowing holes. My gun was held at a 10 oclock position, and I did not weld over an inch at at time, allowing the metal to cool. This patch took around 30 min to weld. I could have done it in 2, but I didn't want it to warp. Something to try, might not work for you, but I hope it helps.

[dzahm 10]

I can concur with Latoracing- that is how I do it. By chance you are not using an extension cord? I have seen ext cords do funny shit with welders, (like a nice weld, followed by weird ones, or blowouts) especially 110v welders (I see yours is 220v-that should be less sensitive to voltage issues) But for the sake of being thorough- you might check your breaker and verify your connections are nice and tight (they can loosen over time and cause weird stuff to happen) Check the hot legs, and the ground, and any electrical connections between the breaker box, and the welder. One last thing- when you convert to gas- you typically go up one or two settings as the gas will cool the weld- so if it worked on A before the conversion I would expect at least B or C. Remember the 3 rules: clean, tight, hot

[Mike65 475]

Thanks for the tips & info, if it cools off this weekend I will give it a try & report back how it worked.

[Kris 90]

Make sure you tack weld all the way around what you are welding before you attemt to weld it solid. If not it will warp. It is best to only weld up to a couple inches at a time or the metal will get to hot and blow a hole. You may not have your gas up high enough either. I run mine at 15-20 but it depends on how good of a welder you are. Some people go up to 30. If your welder is popping like it does with flux your gas is to low. Also when you switch from flux to gas you have to change the polarity of your welder. This is extremely important or it will NEVER work correctly if you dont. It should have a diagram on your welder as to which way it is suppose to be. We have a $3k welder at my work that will do flux or gas and my 110v unit at home would out do it. I got to looking at it and one of the guys that had set it up didnt change the polarity for it to work with gas and it would blow through anything. Hope this helps.