Welding (MIG) Aluminum

[Root Moose]

I'm thinking about making a roof rack for the XJ to replace the factory rails and such; something similar looking to what is on an Escape or an Xterra (but cooler of course!).

Is there a special technique to using a MIG on aluminum?

Pointers?

T!

r@m

 

[CLb33fyXJ]

yeah you need a spoolgun for your mig machine. and use pure argon as shielding gas, not c25 like you would use for steel.

 

[CRASH]

yeah you need a spoolgun for your mig machine. and use pure argon as shielding gas, not c25 like you would use for steel.

You don't NEED a spool gun, just use a different liner for your aluminum duties. A spool gun guarantees you won't bunch up wire, but for light duty, and if you are careful about your cord, you can get away with running AL throuhg your regular 10 ft lead.

You must use pure Argon, however.

 

[Root Moose]

Thanks guys.

So, I have an extra wire feed for my SP170 that I have never used.

So I can just get a spool of AL for this gun and practice a bit and be good to go?

I'm a drag the pool type of welder (really don't know aht I'm doing to be honest ), same sort of technique for AL?

r@m

 

[Ludakris]

its been awhile, so this might not be any help, but if I recall, I had to speed things up a bit... the pool reacted a lot quicker than in steel....

 

[Captain Ron]

Wire feeding Al is not very pretty if your not well set up equipment wise.

Even with a good liner, without a "push-pull", the wire WILL snag, resulting in a jumpy feed. Mega splatter and crappy puddle control. A spool gun helps, but I've had mixed results with them as well.

Try E4043 before E5356. Chem etching the parts will also help a great deal. Do a couple of test pieces, wire feeding AL tends to have penetration problems. A 2:1 Helium mix can help, just remember the flow rate has to be quite high.

TIG would always be my choice, unless you have access to a purpose built robotic system

--ron

 

[BrettM]

MIGing Al is a royal PITA. the welds will look like crap (compared to steel MIG or Al TIG). for just a roof rack, sure, go for it and grind down all the ugly welds, I certainly wouldn't do anything structural with it without a TON of practice.

 

[Lincoln]

That's odd. I don't remember mine looking that crappy after I started moving fast enough. I'll have to uncover the boat this weekend and look.

Tips that I can give.

Practice a bunch before trying to do any real work.
Haul ass. Easily double the speed you mig steel.
Crank the heat way up. I was welding 1/8" and if I remeber correctly I had the power on 8 out of 10 on a miller 175.

Tips I got the first few try's.
1. Jesus christ your moving way too slow.
2. Are you a damn idiot? You need to move twice that fast and get they heat cranked up.
3. I told you twice that fast. Speed it up a little more and you've got it.

I used a standard steel liner dedicated for aluminum. The teflon liners wear quickly then you start getting binding. The only time I bird nested it was when I got an occasional "pop". It would weld the wire to the tip and all was done. Get extra tips. I had a hard time not trying to set the welder up to sound like steel. Listen for a constant buzz.

90% of the welding on boats around here are done with mig. Tig is used around the windshield frame and the inside corners of the transom for the pretty weld look. Any welds that will be ground or are hidden are migged. The mig welds look like a smooth bubble where you see the dime look with the tig welds.

I suck at welding though.

 

[Bloose]

Could you rent a TIG welder for a weekend? TIG on Aluminum is the way to go. MIG may work with practice but TIG is sweet.
B-loose

 

[CLb33fyXJ]

yeah its great and looks pissah, but it would be real tough for a new welder to try to tig aluminum pipewelds for the first time. i think he would be better off trying to find a spool gun, but thats jmho

 

[Bloose]

Aluminum is tough to work with all around. I personally think TIG is easier to get good results than MIG on Steel but I've never actually TIGed aluminum. If I were to MIG Aluminum there is no way I would do it without a spool gun though.

B-loose