Did a search and didn't find anything so.. How do I setup my TIG machine for aluminum welding? I've got a miller dialarc hf, with helium and argon tanks. Also have green 1/16" tungsten, how do I ball the end of it and how thick of metal can I weld with it?

 

use a piece of copper on dc to make the ball and to weld alum go ac
so basically ur just gonna do the opposite of what your doin for mild steel 1/16th tungsten is really small never welded with anything lower than 3/32 so i wouldnt know but my guess would be 1/8th in plate max.
just my opinon tho
jon

 

i wouldn't worry about balling it, the HF will do it for you. i'd use argon helium will float off, set HF on constant, controller on gtaw and remote most likely if you have a foot controler polarity on ac, white metal is always ac

 

cool, thanks guys.

ede, what do you mean by white metal?

 

White metal = aluminum, mag, soft alloys etc.
For me I set the TIG to DC+ and about 40amps, hit it for less than a second on the welding table and I've got a perfect ball tip. It takes longer to get a good ball tip on thicker tungsten.
Another VERY important step with welding aluminum is the pre-cleaning. Dedicate a wire brush to only aluminum and use acetone to clean it before you weld. Any oil from your hands will make it difficult to weld aluminum. Another tip of advice... get a bunch of argon with 15psi if you're working in a drafy room, 10psi if the fumes of the welds are going into your mask
Good luck.

 

finaly got a little time to try it out today, set the hf to constant, remote amperage on, remote contactor on, argon at 15 psi, ac power on middle setting (40-155). first weld didn't even get 1/2 penetration, second weld (upped the power by 10%) got a little more then 1/2 way through (was trying on 1/16" aluminum sheet)

 

second weld

 

Looks like you need to practice your sign off

 

just need to practice period, thats my second and third time ever trying to weld aluminum. i'm just happy to get it to stick at this point

 

Looks waaayy better than my first couple of attempts man you should have seen it

 

been tig welding stainless steel for 3 years (and trying to weld everything else that found its way on my table, lol), that probibly made it a bit easier for me

 

Let me say that you definatly have some experience. Those look really good for the first time. My firsts didn't even butt joint. I was just working on pooling and "seeing" the pool. Then I worked on adding filler. Then speed. Then I did some "art". The hardest thing to do is thin sheet onto thick tubes with acute angles. I've given up and just added enough filler to make a web .
Your sign offs do need a bit of work. I find it useful to almost lift half way about 2 inchs before an end and then try and walk it in to the point where the arc is almost gone. This way the filler goes all the way and I don't get round coners . I'm sure more experienced welders could give you some of there tricks, I'm still new to this.
Oh, and the easiest stuff to weld; Titanium. Our FSAE car has a bunch of Ti and other than having to work in a bath/bubble of argon it's really REALLY easy. Easier than any steel.

 

try pulse i like to pulse aluminum

 

i've welded titanium once and it was pretty easy, it flows really nice. didn't have it in a bubble or anything like that, just had the argon set to flow at 15 psi like i do the stainless and it seemed to work well so.. :shrug:
i've tryed copper tubing too (with the machine setup for stainless) that didn't work to well, need alot more heat then i'm used to and there is only a short time to work it before it just melts away. but i have no idea how thick the metal was and welding to tubes side by side is a little difficult anyway.

have any of you welded stainless before? i'm trying to figure out what color the weld should be after

jocww: what do you mean by pulse?

 

Yeah, what is pulse? I use a square wave TIG on a/c with the defual settings for aluminum.
As for welding Ti in a bath, it's almost required for anything that isn't just art. Ti welds that discolor a lot are bad and brittle. They're so weak that you could break it with little effort. Our FSAE cars suspension mounts were double shear welded Ti . One of them broke from being contaminated, the others are still strong!
We first tried bending sheet Ti, that didn't work too well (cracked).

 

say your going remote and you have a pedal right. say you go down all the way and then up a lil and then down again. thats almost like pulsing it changes the amperage so u dont have to use filler. or u can use filler to.

 

i got it, thanks

 

Your stainless should have a blue color when you have your heat set right.

 

i thought it should, but when ever its a metalic blue color i only get about 1/4 penetration.. only way i've been able to get better penetration (3/4) is by turning up the amps, but then the weld is real dark and looks over headed