Alum MIG - I've lost it

[1havnfun]

Hi All,

I am attempting to re-educate myself on alum MIG. and failing.
It has been over 6 years since I have done this proceedure and have found that I am having a more problems than expected. The project is 3/4" 6061-t6 simple fillet two sides. Clean material with lacquer thinner and a ss brush. Pre-heat the pieces. 100% argon, spool gun 4043 wire, I have 3/64". I know 1/16" would be better, just starting with what I have in stock.

Results using start parameters from the calculater at 29 volts+/-
adjusting the wire speed
result: crap. looks like burnt rabbit poo

I have moved voltage up 2 and down 3volts have ajusted wire speed all over the map, checked for leaks in the argon supply. I am out of ideas. I moved the weld speed so fast that it was ok but lacked penetration.

I could really use that one piece of info that I am over looking.

Thanks in advance
Harold

[jpence38]

3/64 wire is just fine. It sounds to me like you are dragging your puddle rather than pushing it.
Also, set your volts between 22-28
amps between 130-290
wire speed between 235-375

The most important part is pushing your puddle.

Hope this helps.

[Alumaweld]

Alum MIG - I've lost it

What machine are you using? How hot is your preheat temp? 29 volts is a lot for 3/64 wire. I have never gone over 26 volts using 3/64 wire but I use 5356 wire so the setting may be different for 4043.

[Meltedmetal]

I don't claim to know zip about aluminum mig but is that "in stock" wire left over from 6 years ago? If so a new spool of wire wouldn't hurt.---Meltedmetal

[Goodhand]

1. You did change polarity when changing from steel to aluminum?

2. What is the tank pressure of your Argon? If low, then it may be picking up water vapor, combining with the Argon.

3. Are you welding anodized alum?

[aametalmaster]

1. You did change polarity when changing from steel to aluminum?

I hope not. Solid Steel wire and aluminum both run gun +...Bob

[MMW]

When I do heavy aluminum with my MM250 with 30a spool gun. I watch the puddle carefully as soot tends to build up at front of puddle sometimes. Then I stop, clean & restart or I get a hole in the weld.

Gun to positive!
straight argon at about 30 cfh
28v & about 4.75 to 5 on wire speed (any hotter & it is crap)
preheat to about 200?
3/64 wire 4043 for 6061
slight push angle on gun, maybe 10 degrees?

[1havnfun]

Good info, all

I am using my xmt350 with a spool gun
I have my argon a little low on volume, running around 20cfm so I will turn that up
gun +
200 to 220 preheat
I am pushing but I think the cfm being turned up should help with the shield
The wire is old but it is kept in a sealed can
I've been looking at the plate I am using to re-educated and the oxide layer is really heavy, so I will be using all the info presented here and I will take a mill cut on the surface before the final cleaning, just in case I haven't cleared it off all the way.

you all are the best, thank you
HH

[Goodhand]

I hope not. Solid Steel wire and aluminum both run gun +...Bob

Oops, tired mind thinking flux core.