Aluminium TIG Practice

[malcolm]

I tried out aluminium TIG for the first time today. Seems easier than my efforts with mild steel, though the mild steel was 0.8mm. The aluminium seems more gloopy and seems to fill gaps better.

Practice was interesting. I was running just over 50 amps on 2mm aluminium sheet. It might have been a little low as the build up seemed to be very sensitive to how wide the puddle was at the very start of the weld, and insensitive to what I did along the way.

Quickly got bored of practive and tried welding a seam on a home made pipe. Worked really well with good penetration too.

Next to weld the pipe in place. This is an exhaust heatshield. Definately running too few amps here. It started off nicely, but I took too long repositioning the shield for the various angles and all the heat went out of the aluminium. Also there are some inside corners in there that would always benefit from more heat.

The whole thing was planned out so that the welds are hidden apart from the one on the top of the photo, which turned out to be the worst one!

I'm keen to start making some more aluminium bits - bit more practice and figuring out to do especially on positional welding.

Great fun though and having the pipe turn out so well was really satisfying.

 

[irondarren]

looks good to me, but then i have never Tig ally. Done mig on ally and that was fine but never TIG.
Malcolm did you get chance to look at the pdf's on the link i sent

 

[Hitch]

That looks really good Malc, especially for a first timer!

 

[malcolm]

looks good to me, but then i have never Tig ally. Done mig on ally and that was fine but never TIG.
Malcolm did you get chance to look at the pdf's on the link i sent

First photo I'm happy with, second is flattered by the light. Ought to have got the settings right using test pieces before tackling the job. Might try the test pieces tomorrow to figure out where it went wrong (probably trying to tackle fiddly positional welding before I've got the hang of controlling amps on the foot pedal.)

Thanks for the PM. Had a look through and have some ideas. Program still running in the thought process.

 

[shenion]

Malcom, looks good.

I find different thicknesses of Al give different results. My first try was butt weld of 1/8" stock. Worked well.

Then did some 0.090 and it was more difficult especially without a footpedal.

TIG is a lot like stick. You practice all day long, then do something real that is slightly different and struggle.

One of these days, I'll get back to building a coolant reservoir for my Jeep.

What filler are you using? I found 5356 easier than 4043.

 

[malcolm]

I'm using 5356, at 1.6mm thickness (thickest I'm likely to weld is 2mm sheet).

I reckon getting the hang of the foot pedal would make life easier. I'm still using panel control for amps. The main thing that seems to be catching me out is the heat transfer away from the weld. Tricky to get going and then need to speed up as I go along (unless I start off with too much filler wire).

Probably a foot pedal would help with that, just I'm having trouble getting the hang of it.

 

[Weldingartisan]

Malcolm, if you are welding butts at 50amps you will need about 70-80 amps for a fillet on the same thickness of ally. Very good for a first attempt though. I use 5% silicon filler on sheet and 5% mag on extrusions and castings. W/A

 

[shenion]

Hmm, that is a heat shield? 5356 is not supposed to run at > 150F, something about the mag separating and corroding.

Probably will be fine though as it is non-structural.

Using 4043 I found I needed the foot pedal. It melts before you get to the weld pool so you need to use pedal to lower current on each 'dip'. My first attempts were without a foot pedal and I did fine with 5356.

Oh, thicker steel is a breeze. I patched a hole in the Airco case with TIG (1mm). Fill a bit, blow half of it away , let cool, retry. Finally got half decent. Then did butt weld on 1/8" steel and was piece of cake

I found a neat trick. I had MIG'ed some test pieces. Had real cold starts and was tall. Used TIG and flattened them out. Might be useful, do fast MIG then clean up with TIG.

My gas setup has been f'ed up for a while. Finally fixed leak in mixer, but still waiting on ball valves to do it right. Then I can shut off the MIG and TIG ports rather than reconnecting hoses each time (the TIG solenoid turns on on ARC/MIG, need to shut ff.) Should be going this week; then I'll get back to the Jeep coolant reservoir.

With no gas, been practicing a lot with stick.

Still awesome work in the heat shield

 

[malcolm]

Thanks Weldingartisan - sounds like that was the problem later on. Ought to have practiced a little more, though with MIG I'd have turned the amps up - there's more metal to melt when you are welding at an angle. Probably generally low on amps. Might have a play with more amps going faster.

Found an article on the 5356 on the fabricator. Sounds like it might harden a little and be more succeptable to fatigue. No worries for me - any fatigue problems on my bit will be down to poor welding.

I tried running over part of the weld again with TIG but the arc didn't seem to want to melt anything and I had lots of odd sparkles on the surface. Though I don't recall if I cleaned off the oxide thoroughly before I went over it - it was getting late. Done the same on steel though.

I'm a little more enthusistic about the TIG now. I've got a stainless steel strut brace to make this week. It's 2mm tube welded to 2mm plate and it would be really cool if I could end up with a neat TIG like weld. I've got plenty of spare tube so can have a lot of practice.

 

[malcolm]

Well the stainless was a pain. Then I found the stainless tig thread and realised it's supposed to be like that! Evil nasty stuff. Going to try some really thick mild steel next before the gas bottle runs out.

Figured out the foot pedal though - it doesn't work when the start current switch is switched in. Will have to read the manual.

 

[shenion]

I have a sheet of "Mystery Metal", 1mm thick.

I thought it was stainless. Tried to TIG an overlap and all can do is burn metal back. Did manage a bit of weld. Odd stuff.

I would like to try Ar/He mix, sounds like would help het more heat into metal in a smaller area.

I'm wondering if it might be some MuMetal shield.

Stainless is on my list to try. Sounds like it takes a lot of heat, smooth gas flow and a real close torch.

Malcolm, I did some 1/8" hard steel (bed frame), was real easy In fact it was my first try at TIG: "Oh, this is easy". Then did some thin steel and Al; Entirely different beasts

 

[malcolm]

Must admit I've still not tried thickish steel. Though if I were ever to write a guide to learning TIG to a basic and shaky standard that would be the first recommendation. Starting off with thin and exotic materials isn't the way to improve confidence.

After my first attempts at stainless I wouldn't go hot. The reverse of the weld seems to need shielding if you penetrate through. Attached photo is the reverse of a practice try. Tried MIG too and it did the same. Evil stuff. Though the mess grinds down well.

 

[deuce bigalow]

very good mate even for a beginner. couple of tips for u if you want them,
1.dont be scared to put a lot of amps on the pedal its like drivin a car u can go as fast or slow as u want.especially if u are welding materials of different thickness
2.everone will tell you that you should have tig torch at bout 30 degrees to the plate. i have found that the more verticaly u hold the torch the more direct penertration and circular bead. but i'll warn you it takes practise
3.try not to rest the torch on anythin,with ally the shroud can get stuck in the cooling material and or u get drag makes. also if practising freee holding the torch while well will make u become a more proficient welder.