Mig welding question

Some of you guys have much more knowledge than me about welding. My question is; what do i have to do to use my mig to weld aluminum? Do I have to use another gas other than argon? I obviously need a different type of wire but what else?
Thanks

Mike
86 Carrera t

You will also need a spool gun, (spool of wire attaches to the handle) the aluminium wire won't make it through your cord without bending or jamming. Mine was about 350.00 for my millermatic. Yes, use Argon.

Hope this helps
Tim in Sac

I have had no problem running the large spools. The spool guns and little spools are a nice way for the welding supply stores to make extra bucks. Tim is correct about binding but you can make some adjustments to help everything work. Change the liner. Install a clean tip. Line up the welder so you have minimal bends and then the wire should make it. If it is still binding try it with out the tip. If the wire feeds, then the tip is too snug. I have used tip cleaner/reamers to loosen up the fit and that helps too. I bought my own liner that I kept just for aluminum. Migs tend to get beat around a bit and the old liners get a little dirty and beat up from being coiled and kinked and generaly used and abused.
one more thought. even the burr on wire from the wire cutters can cause it to hang up when you first try and feed it to the gun so take your time.
Good luck
david 89 turbocab

[This message has been edited by 5axis (edited 05-11-2001).]

What is a liner and when do you use Argon, when do you use other gases, if any? Thanks!

Oh David,
Thanks for the suggestion, I watched "Junkyard Wars" and it kicks ass! I saw them weld with what I believe was a MIG. Seems quite easy. Thanks for all the help!

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Jeff
1976 911S

I'm no expert, but here is what I know.

The liner is an inner sheath inside the cable that runs from the welder to the stinger (the working end of the welder). On my Lincoln you use a different liner for aluminum.

Argon is what is used for aluminum. I run an argon/co2 mix for mild steel, but you can run a straight co2 shielding gas.

I can't remember exactly why I decided to go with the mixed gas though, I think the teacher in my welding class recommended it.

Charlie
'72 911 TE

Change the liner and possibly the drive wheels(depending on make of welder). Use 100%argon for aluminum, blends work on mild steel and are cheaper. Check that the welder is powrfull enough to weld aluminum. It takes alot more current to weld aluminum.
Good Luck
Kevin

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KEVIN WOOD
70 911E TARGA

Thanks for the replies! I got the liner and aluminum feed wire, now all I have to do is try it out. My mig uses 240 volts and for mild steel, the setting is always on low, so I think it is powerful enough for aluminum.
Any tips on how to actually weld? Is it the same principal as mild steel, or is there a different method?
Thanks guys

Mike
86 Carrera t

If I'm not mistaken you will also have to reverse the polarity of the ground clamp from -ve to +ve if the last thing you were welding was steel. That will make the tip potential relative to the ground clamp -ve.

Hello

Well I prefer TIG welding.

But allways:
Cleanyness is the utmost important.
Use a stainless steel brush to scratch the welding joints free from oxide and then wash everyting with Tri, Aceton or Methylalcohol.

Never mix up welding tools or use contaminatet tools.

Also very important is to find out what alloys you will weld. The welding material should allways be higher grade.

Also there are many other little tricks like starting to weld on a separate sheet and remove it afterwards. Also you can play with polartyfrequency, phase and amperage lifts......

A small transformator will need very much time to cool down inbeetween the welds. normaly the hobby units have under 5% ED under max power. Good uints will have up to 20% ED ( ED stands for Einschaltdauer witch means you can weld 50% of the switched time ). Keep this in your head if you are at the limit and will weld a longer seam. Hevey stressed transformators will also start swinging and spotfireing the amperage.

Check your house curency if it will bear the amperage suppley to the machine.

The best is to get some aluminum and test out the welder and then give yourself some practice.

What ever you weld keep in mind that you have to depend on your work. On very hazourdos parts like Rims, Brakes, Rollbars leave it to a approved expert. Or ask an expert for support and let X-ray or flux the parts for your own saefty.

Also welding machined parts or forged alloys will change dimension from them ( heat warp ) and/or alloy integrity ( softening ).


Pure Argon is the best but a 99% mix will also work.

Wrong Gas will look like the part is from the secound generation terminator....

Avoid working on windy areas and even let not blow the the weldercooler on there. But keep in mind that if you make more than average to wear a external air intake mask or use a dust extractor ventilation to refresh the air. Some Alloys do develop toxic gases......better ask before finding out yourself.

Straigt CO2 will support deeper seams on steel and is used on heavy sheets. CO2 mixtures ( blends ) do support different things. Mostly they make the weld wider allowing to "fill" and avoid blazing with those little melting balls on the sheet.

Grüsse