need advice welding aluminim

[rcracer]

I bought some 1/8" thick aluminum from homedepot and trying to learn how to weld it. I can weld steel just fine which seems more forgiving to the untrained. I have a Clarke 135amp MIG welder, using 100% argon, Lincoln electric 4043 wire and have tried various feed speed and current settings all with the same result. It just blops up on the alum or is runs off. I have cleaned the surface and still the same result. it almost seems like the wire melts to quickly so when I turned down the current it made poor contact and sparked.....do you guys think I need different wire?

thanks for any help

[Cole82]

Sounds like you need to preheat the aluminum. A 135 amp welder is fairly low out put.
What did you clean the aluminum.
Have you tried holding it in one spot. To see if it gets hot enough to flow?

[rcracer]

I used a wire wheel to clean the surface to a dull finish. I did hold it in place but it still didn't stick, just check blobbing and jumping welds. I'll have to try the preheat later today with my torch.

I would have thought a 135 amp would be plenty since alum melts at a lower temp than steel, is that wrong??

thanks

[chaotic_life]

I assume it is a traditional wire feed? because aluminum is notorious for being a pain without a spoolgun-it tends to kink very easily, which drags in the housing. I also assume you have it set up for AC, right?

[Cole82]

It has to be a stainless steel wire brush.
Read this and see if it helps.
http://www.lincolnelectric.com/knowl...ntent/alum.asp

[hp_chevy]

i thought that you use tri mix on alluminum?? or is that stainless???

[blazed]

you use tri mix on stainless

[rcracer]

Thanks guys, it's an AC welder, it is a wire feed (push). no problems kinking. I looked at that link and I'll try some of the tips regarding cleaning the alum.

[mikeygixxer]

itd be better if u can tig it.. you can control the heat better, beware aluminum will blow apart!!