Welding Aluminum

[88_pacifica]

Hey guys.... Crazy question here... I think I remember reading somewhere that a stick welder can be used on aluminum and it doesn't have to be done with a TIG welder. Also, I'm not sure if it is MANDATORY to use a gas, as this escapes me too...

I know that it is not the recommended way to weld, but I have two old intercoolers(SAAB small ones) and I thought I might mate the two together into one bigger one. This would fit my car perfectly, but I'm not even sure if they sell aluminum welding sticks. Plus, being that the intercooler is relatively "thin" this might be a bad idea as well. Post up some opinions...

And , dammit, I know a new or "one piece" unit would be better/easier/ etc.... just want opinions and a few facts. Thanks all!

[BadAssPerformance]

Never heard of stick welding or even gasless welding of aluminum. Can you A/C or high frequency weld with a stick?

Aluminum REALLY likes to be clean during welding too.

TIG or MIG with pure Argon as long as the welder can do A/C high frequency welding. Depending on how thick, you'll need some amps too, Full pedal on the Miller Syncrowave 250 I use is 300 amps and I've used all of it on aluminum before.

[RoadWarrior222]

There's some sticks for aluminum, meant to be for DC only and very tricky to use. I have heard they don't like cylinder head alloy.

How hot do intercoolers get, there's some aluminum solder that might be easier to work with, but I think it melts around 250C so obviously needs to stay cooler than that.

Edit: found linkage for sticks...
http://www.zena.net/htdocs/welders/Rods/Aluminum.shtml

[88_pacifica]

Hmmm.. well, it was just a thought and I kinda figured the same thing because without the gas and "heat" it would not bond properly. I know that with steel it's largerly an "electrical" reaction versus the temperature reaction with aluminum. Thanks JT and I guess I'll sell them outright and get a different one.

[88_pacifica]

Very interesting roadwarrior... I thought I had heard it was possible. I would be scared of burn-through though. Hmmm... I would like to try it sometime to see how it works. I GUESS it has the same principle, but I had never considered it before without gas...

Imagine if you could get good at it the money it could make you with the low cost of an arc/stick welder.

[looneytuner]

There's some sticks for aluminum, meant to be for DC only and very tricky to use. I have heard they don't like cylinder head alloy.

How hot do intercoolers get, there's some aluminum solder that might be easier to work with, but I think it melts around 250C so obviously needs to stay cooler than that.

Edit: found linkage for sticks...
http://www.zena.net/htdocs/welders/Rods/Aluminum.shtml

I have used the "solder" type. It's not for cast. It melts at about 1700? Just shy of the aluminum melting. Northern tools had it in their catalog.
I wouldn't recommend it for anything that cost some money. I used it for i/c pipes. It requires at least oxy acetelyn.

[guyd_15]

I've tried gas welding aluminum. Gas welding was used a lot in the aircraft industry in the 1940's. Even gauge thickness metals were welded this way and there is no bird nesting like with a mig gun. When using a mig for aluminum you really need a push-pull gun, even then the wire will occasionally bird nest.

I made some pretty good welds, some not so good. With some practice (like all other types of welding) and patience a good bead is possible. And the brazing set up is much less expensive than an aluminum capable mig machine. I used an oxygen/acetylene set up with a small brazing tip. The aluminum filler rod was from addifix. The metal needed to be very, very clean! I used emery cloth, then aluminum cleaner (any welding supply store) and I followed up with brake cleaner.

I think Aircraft Spruce sells a training video that demonstrates the process.

Good luck, be patient.
Guy

[RoadWarrior222]

The solder stuff I was thinking about is a paste you can use with a propane torch, think it's intended for fixing AC condensers etc.

[boneyardracing]

The solder stuff is called alumaweld its a form of brazing.

[RoadWarrior222]

Different stuff than the one I mentioned which would be this...
http://www.solder-it.com/solderpaste.asp
2nd one down.

Supposedly, silver solder can be got to work on aluminum, I've managed to tack a ground wire to aluminum enclosures with it before, but wouldn't like to attempt mechanical work with it.