Welding Aluminum?

[BrianG]

Is there a relatively inexpensive way to weld aluminum? The online sources I found talk about spending well over $1,000 for just a halfway decent TIG setup. Some say it can be done with MIG or ARC.

However, I don't see myself doing a lot of welding, just the occasional chassis brace and the like. I'm kinda tired of using nuts-n-bolts to hold stuff together...

Then, there's this stuff, which is probably a gimmick, or is probably not as strong as I'd need. Seems too cheap and easy...

Any ideas?

A mig welder can be used for aluminum (well some can) as long a you get a different welding material and you adjust the speed and current and running a different gas (not the argon/co2 mix, it is just argon (i think). I think you even need a different welding head (thingie).
It is probably not as durable as a tig weld, but that stands true for Mig vs Tig welding in general.

[BrianG]

Hmm, maybe I'll assemble what I want to weld and just take it to a machine shop that can weld it right. The product in the link is about as complex as I want to get with it, and don't want to spend so much cash on something I'm going to use infrequently.

[rootar]

we learned to oxy/actalene weld aluminum at college, it was NOT easy at all very hard to anything thats not a 1/4" thick or thicker, mig welding aluminum with the proper setup is the easiest to learn, MIG on the other hand is BY FAR the most controlled and best you can do.

but the cheapest thing to do in your case would be find someone else with one a dn make good friends with them or take it to a machine shop.

[bdebde]

What are you trying to make Brian? I can tig aluminum.

[BrianG]

Well, I was thinking of re-doing my Revo with a 3.3 chassis. But instead of bolting on the various trays, I wanted to fab up aluminum sheets to match the chassis edge and weld it. basically put whatever Traxxas cut out.

[lutach]

You can give Alumaloy a try: http://www.alumaloy.net/

[BrianG]

That stuff sounds like the same thing in the link I posted above; same price for the same weight of rods, same procedure, and they melt at the same temp.

[lutach]

Originally Posted by BrianG

That stuff sounds like the same thing in the link I posted above; same price for the same weight of rods, same procedure, and they melt at the same temp.

Sorry, I didn't click on the link Brian, but yes it seems to be the same thing. I actually bought it when it came out a long time ago and the stuff is strong. I don't know if they changed it, but if they didn't I might get some more. It might be the only "As seen on TV" item that actually works.

[rootar]

Originally Posted by bdebde

What are you trying to make Brian? I can tig aluminum.

BrianG this sounds like that friend i was refering too that you needed to find

[JThiessen]

Brian, I tried that stuff that you linked to. I am experienced in TIG and MIG welding, so hopefully I can lend some insight.
True welding involved creating a molten pool in both parts that you are trying to weld, with the addition of a filler material. The product referenced does not do that. It relies on surface adhesion. So basically you are "gluing" your parts together. You have to get your parts very clean (and use a stainless steel brush - which I still havent figured the function of yet). You also need to make sure you are doing the correct materials.
I made my battery trays and nerf bars using this product on my E-Revo. They held up for about a year, but then I had to "make them right" using a mig (thanks to my Brother in Law). You will not get a professional looking weld from it, nor will it hold as well as a mig or tig welded part.
A mig will easily weld any of the aluminum that we RC'ers will encounter.

[TexasSP]

Just a quick note but 6061 is better to weld than 7075, while 7075 is stronger and much more machinable. There are some other alloys that are stronger than 6061 that you can weld as well although I am foggy on the alloy number right now.

I will also note that aluminum is one of the trickiest metals to weld due to it's low melt point. Of all the welders I have known and have worked for me, I only know of two that can do a decent job. One guy is good and the other is awesome.

[JThiessen]

Originally Posted by TexasSP

Just a quick note but 6061 is better to weld than 7075, while 7075 is stronger and much more machinable. There are some other alloys that are stronger than 6061 that you can weld as well although I am foggy on the alloy number right now.

Yes, any 70 series (70XX) is generally considered unweldable. Stick with 50 and 60 series.

[rootar]

yea i havent understood the wire brush on aluminum for prep either because thats a receiepe for corrosion (steel + aluminum+ electrolyte = corrosion) and on top of that you clean it with a wire brush right before you melt it to it most vurnerable point only for it easier to get corroded????????

[killjoyken]

BrianG, find a good, experienced TIG welder. A Revo chassis is way too thin to MIG weld properly. I use Miller 251 MIG welder at work and use a spool gun to do aluminum. $2500 for the welder and $1300 for the spool gun. It's great for doing .25" 6061 or thicker, but it's really easy to blow through thinner sheets.

TIG on the other hand gives you a lot more control when welding and the welds come out stronger and nicer looking. If bdebde's good, have him do it.