Is it possible to weld alum (brackets) with a torch (oxy/gas) and alum braising rods? (commonly found at home depot)

or is it a nightmare?

Right now I can weld steel, and make almost everything out of steel - but for things like custom serpentine brackets it would be nice to make out of aluminum stock.

-- Joe

 

If you're using brazing rods, then you'd just be brazing it. If you want to weld it (melt the parent material) I think the brazing rod would be a puddle at your feet once you get the parent material hot enough to melt.

Using a torch on aluminum normally kills the heat treat like crazy, because it throws so much heat around. Not only does this hurt strength, it also discolors it really bad. It'll look funny. You can sand/grind but you'll still have heat discoloration/marks. Need to paint it after with primer and another color.
Think of anybody who's had aluminum wheels refinished.


No reason you can't try it though, 6061-T6 is pretty common and relatively cheap. AL TIG rod is what you'd want to use as a filler rod.

mcmastercarr.com p/n 7972A297 would probably work ok.

 

Hrmm. Good info thank you.

I wish I had some better gear. I have two 120v stick welders, and 2 120 volt wire feed. One is a MIG, the other fluxcore. I can't weld alum with any of them (to my knowledge).

I've seen alum mig wire at sears before, but I've been told you need a 240 volt mig or something like that. I dunno. I've been welding for almost 20 years, but no formal training other than a few weeks of shop class in high school.

-- Joe

 

You can MIG weld aluminum.

 

Yes, with straight Argon and if your wire feeder doesn't jam. I don't know how well it would work with a little 120 wire feeder though... The biggest thing of aluminum is to make sure everything is clean, wire brush your materials at the least. Also try preheating pieces before welding.... Its been a while since I've messed with it but I think you are supposed to pre-heat it til its gets shiny... I think.... Oh & practice... preferably on scrap first.

 

The main thing is the ridiculous amount of current it takes to weld AL. Take your generic piece of steel to be welded, now make it Aluminum and you need almost double the amperage.
That's why your 120V welders probably can't handle the task. The AL will whisk the heat away so fast it won't make a puddle. You'll just end up heating up the piece.

The stick welder, with a cheepie air cooled tig torch and an Argon bottle will let you TIG weld. What's the max current of your stick welders?
I bought a WP-9 I think, off Ebay for $60. That's 25' of welding cable, and shielding gas cable, and the torch. Got a regulator for $25, and a "kit" for $12 I think. $100 all in to make my stick welder (a lawn mower engine and a ford alternator, but that's besides the point...) into a TIG welder.
But I have ~130A of current available, so I should be able to weld thin AL. A 120V welder is probably maxed out at 90A. Read up on stick/TIG filler rods, and the recommended current use. That's the crux of the story here.

 

Find a place that will Heliarch it and be done with it. We found a local place for my buddies broken trans bell housing and they took care of it in a day for like $25.

 

I don't think you understand. I want to be able to start welding alum in my shop. I can't make everything out of steel. Plus if I need to weld to an existing part, etc.

Looking for advice from the pro's.

Sonix: The stick welders are like. 60 amp or something like that @ I think 12v. (They are your basic $200 120v stick welders).

I appreciate the info. Looks like It ain't happening for now. I'm not spending $1500 on a used tig, as it looks like my stick welders and mig welders are way underpowered.

-- Joe

 

If you are planning to start fabbing with aluminum, you have 2 choices that are the most cost effective. A good TIG machine, or a larger MIG. AL sucks up the heat. For pretty, need TIG. For big ol' slabs, MIG is better, or using Helium on DC (Heliarc).

You can use a Oxy-Acy. torch but you need to use flux. the film of oxidation is tough to work through otherwise. The aluminum puddles into coated drops that won't fuse. I haven't tried it yet, cause I haven't found any cheap flux locally.

 

You can get a decent 240V stick welder for a lot cheaper than a TIG. Then you can just add on the TIG. Typically this is a LOT cheaper than buying the "TIG" unit outright.
ie. a $350 stick unit and $150 worth of TIG upgrade parts on EBAY (get a bigger unit than my little WP-9 right?).

 

yeah, thats true. It needs to be an AC/DC unit though, as AL with argon is an AC process, and without much AC control, it's a cruder process than a dedicated TIG unit, particularly without a high frequency start, etc.

I know, I know, it's all bells and whistles, but for any kind of production work to sell or build in quantity, they make the job much more professional.

the heliarc(DC) method is nice, but requires high purity ($$) helium.

 

Yes it can be done. I've seen it done. Unfortunately, I do not know the technique. The one time I experimented with it, I found that the piece turns to mush very quickly. The temperatures have to be very precise. As always, aluminum must be very clean.

There are instructions in Finch's welding manual (he also wrote the instructions on welding aluminum in the monster garage, "how to weld damn near anything" book) on how to weld aluminum with cobalt lenses and oxy-hydrogen, but I read on another aircraft site that this is the old method and that the cobalt lenses were found to be unsafe for your eyes, and hydrogen actually doesn't work as well as acetylene.

I do know the place to start is finding someone who carries an aluminum flux, or else you're just wasting your time.


Mathius

 

Millerwelds.com has a lot of instructional information on their page.. and plus you can go there to drool over all their awesome welding machines & such.

 

You’re sort of all over the place with this thread.

Yes, aluminum can be welded effectively with a torch, to do a good job at it you have to use the proper flux since you don’t have the cleaning action of an ac arc.

Yes, it can be welded with a MIG, but without a spool gun or a Teflon gun liner you have to keep the gun lead really straight, I’ve found that if you have a second person to deal with the logistics you can get away with a normal gun liner. With a 110v welder you’ll probably be limited to effectively welding something about 3/32-3/16”. Most of it will be at full power with a very high feed rate.

Some cheap mig welders, dc arc welders… can be used as a TIG in a pinch, the easiest way is to hook up a tig torch with a built in valve. If you want to weld aluminum with it you’ll need to mix some He with your Ar to “supercharge” your weld, this is the original way that they used to weld aluminum with a tig, which is also where the name “heliarc” came from. It is also still the only way that some high end aluminum welds can be done to meet some standards.

 

Can you please explain to me just how the hell you would use a Wire feed welder for a TIG setup? I guess maybe if you rig the damn thing and hot wire some $hit. About the AC current: the flux does not replace that cleaning action. It replaces the shielding gas that protects the molten metal from the atmosphere.
Plus even buying a TIG torch and hoses is still not cheap. Its gonna run you around 200 bucks just for the torch, hoses, small parts that go on the torch (collets collet bodies, ceramic cups,) and some consumables (tungsten and filler metal.) I bought full professional grade components though, I'm sure there are cheaper beginner sets but "you get what you pay for" surely applies here. Then you still have to buy an argon bottle which is high dollar (but you would need that to wire weld AL anyway) and possibly a regulator.

And sorry but your facts, just like this thread, are all over the place.

So Anesthes, if you're really serious about welding high quality in your shop then maybe look into selling some of your redundant equipment (one 120 wire feed, and both 120 V arc welders) Any TIG unit will allow you to stick weld also, Or if you get lucky and find a REALLY good deal on a multiprocess unit, you would just need to find a wire feed unit that runs off of that machines output power. Of course that last option also makes the dollar signs still flash by quickly.

 

MIG is really the wrong type of power source (a question about constant current vs constant voltage), but some cheaper migs out there work fine for it, one of the local killer fabricators uses a cheap Chinese mig that he picked up as a TIG on the mobile trailer that he drags to the track (ministock cars).

How to do it? Most migs have a plus and minus screw terminal inside the cover with the wirefeed. Connect the power lug on the torch to the minus, and leave the ground connected to the + and go for it. Cheap knockoff migs have the gun always energized so at that point turn it on you’re ready to go. A more expensive mig will only have the gun energized when the trigger is pulled, so just pull the 2 blade connectors that plug the gun switch in and make a jumper with 2 blade connectors (if it bothers you that the motor is turning with no wire going through it then just unplug it or even rig a switch. If you want to get really slick, mount a thumb switch on the torch and hook it to the gun terminals in the mig and then you can even use the mig machine’s gas valve to control shielding gas for the tig torch (you’ll need to use a tig torch with a 2 piece cable or an “R” cable with an adaptor block).

That depends on the type of flux. That is true for arc welding electrodes and some flux core wire, but soldering or brazing flux is strictly there for cleaning the surface to promote better adhesion. The flux used for gas welding aluminum dissolves oxidation and keeps it from oxidizing when you apply the torch, it does not make a shielding gas.

Ok, at this point I’m debating if you’re just being a pain in the ***, missinfomed or what.

When I built an alternator powered TIG I picked up a new weldcraft (pretty much the standard in tig torches) WP17V-25-2 (valve on body, 25foot 2 piece cable) on ebay for $23 and a “kit”in a package with .040”-3/32” collets, cups… and a couple of each size tungstens for $12. I use a miller diamondback (which is also a weldcraft but with a cool blue diamondback rubber grip) WP17-25-R on my miller synchrowave. No cheesing out on torches…

Originally I used the regulator assembly from my mig setup (and in a pinch I’ve even used the C25 bottle on steel, it’s better than nothing) with the alternator tig, so that basically cost me nothing. I found an “inert gas flair” (the rounded seat flair that they use to connect shielding gas connections) to connect the torch at the local Robert’s Oxygen for $2.

Not that I see what the point is, since no matter how you plan on TIGing something you’re going to need to buy a torch and consumables, and for that matter, if you plan on gas welding or mig welding aluminum you’ll have to buy appropriate consumables, gun liners, flux…

Yea, I know, I don’t have a clue what I’m talking about, the funny thing is that I live in this strange little world where I’ve actually done this stuff before, and some of these ideas I picked up from one of the best metal fabricators I’ve ever seen (a few years back he got paid by the national parks service to go up to NYC to be one of the “skilled artisans” that restored the statue of liberty).

 

Hey anesthes, if you already have a stick welder you can weld aluminum with aluminum electrodes. 60amps is plenty to burn the smaller electrodes. You certainly do not need to double your amps to weld aluminum either. Particularily using SMAW (stick) I generally turn the amps down slightly when switching from a steel electrode to aluminum. Many welding supply companies carry them. They aren't cheap but certainly a lot less hassle than trying to rig up a mig powered tig or fooling around with the oxy-fuel torch.

http://www.esab.com/global/en/products/consumables.cfm