Aluminium tig guide getting started.

[Cheesie]

I have seen that on youtube videos. No cracking apparent. The ali is 6mm x 60mm angle of unknown properties. Probably was part of a carport or similar. For this job it was good enough. No issues. The angle was cut 45 at deg. So the corners were knife edges which fused back to form a nice bead.

I would point blank refuse to do it on a carport, fusing has limitations

 

[prepman]

I would point blank refuse to do it on a carport, fusing has limitations

Think you've misread my post. It's the scrap material that's been recovered from possibly a carport or a barn or a who knows?

 

[prepman]

Not too bad, but not too good.
Using very dirty and greasy stock.

 

[gasket999]

I was going to put this in a separate thread, but as it concerns learning - it might be more appropriate here:

I've just bought an AC Tig set from the forum and (once its repaired) I'll be practicing and practicing in order to (ultimately) let me do welded repairs on 0.040" (1mm) aluminium bodywork. Butt welds and hole filling primarily.

I've read the whole of this thread (thanks Richard!), but wanted to know what thickness of aluminium I should use to do my practicing? 3mm? 2mm? 1.5mm? 1.2mm? 0.9mm?

I wasn't sure if it was better to start really thick and creep up on the thinner stuff or whether to start at 1.0mm (which is referenced as being OK earlier in the thread).

Another question is whether anyone knows of a source of practice sheet? - in the US they often sell 'coupons', small strips of plate at reasonable prices.

 

[Hood]

I would start at the thicker end to get the practice in.

If you want to pay for postage I can give you lots of scrap bits of 5mm 5083 and maybe some small bits of 6082 sections but they will be small bits

 

[Macfun]

In my newbie's opinion, start with 2-3 mm thickness.
And/or make "blank" beads on 1 mm, to learn.
I have lot of 1mm and 1.5mm aluminium and beads results were not good-looking, which was not too motivating.
Learning on a little thicker eases a lot puddle control, and beads appearance.

 

[Mark 2]

A pedal is essential, if you don't have one.

Edit,
Just saw the other thread.

 

[Kram]

I've been learning on 2mm sheet, its a good thickness provided you have a heatsink under it, which I use a bit of 16mm alu.

 

[Hood]

A pedal is essential, if you don't have one.
...

I disagree, never use a pedal myself.

 

[Mark 2]

I disagree, never use a pedal myself.

Don't need, don't like, technique alternatives?

 

[Hood]

Don't need, don't like, technique alternatives?

Don't need and don't particularly like them. Pedals are fine if you sit at a bench to weld.

 

[Munkul]

A pedal is essential, if you don't have one.

Edit,
Just saw the other thread.

Agree with Hood, absolutely not essential at all. It was years later that I got a pedal for AC tig and even now i rarely use it unless it's particularly fiddly and can be done on a bench. Just set your amps right and use the slopes.

 

[ukracer]

Agree with Hood, absolutely not essential at all. It was years later that I got a pedal for AC tig and even now i rarely use it unless it's particularly fiddly and can be done on a bench. Just set your amps right and use the slopes.

What do you use instead...

 

[minimutly]

Agree with Hood, absolutely not essential at all. It was years later that I got a pedal for AC tig and even now i rarely use it unless it's particularly fiddly and can be done on a bench. Just set your amps right and use the slopes.

Yeh, this - “set your amps right and use the slopes” . Problem is you don’t know what the base setting should be (ok, you would, with some planning and google), but using the slopes is another skill beyond actually forming a pool, keeping a short arc, not dipping, knowing what speed to proceed, when the job is heat saturated and about to collapse...
I do feel that a pedal takes at least some of this overhead away, and experienced welders forget how difficult it is to master this art.

 

[Macfun]

A pedal is essential, if you don't have one.

No need IMHO, it's an additional thing to manage, while you're busy trying to learn handling the torch and the metal fusion.
I have one (and a pulse box), and I'm still learning making nice beads without.

 

[Munkul]

What do you use instead...

Yeh, this - “set your amps right and use the slopes” . Problem is you don’t know what the base setting should be (ok, you would, with some planning and google), but using the slopes is another skill beyond actually forming a pool, keeping a short arc, not dipping, knowing what speed to proceed, when the job is heat saturated and about to collapse...
I do feel that a pedal takes at least some of this overhead away, and experienced welders forget how difficult it is to master this art.

I use the torch button and slopes. Set to slope up and down to around 25% main current. Slope down is about 3 seconds, slope up maybe 1.5.
There's a mode that a lot of machines have enabled by default, and some have it buried away as a configurable option, called "2T arc restart". This means when you let off the button in 2T, it slopes down, but if you press and hold the button before it's extinguished, it slopes back up. With a bit of button tapping, you can control the heat level pretty accurately, without a pedal in sight.
That's my technique for smaller awkward bits anyway. Long seams it doesn't matter as once you get going your amps should be pretty steady, I'd weld in 4T so I wouldn't have to hold the button all the time.

As for main current, you go with whatever it takes to puddle in a few seconds generally. If it won't puddle then you need more amps. When a workpiece is large, and stone cold, you have to bump the amps way up. and after it warms up a bit, drop the set amps a bit.

You maybe don't realise, but going on the workshops I've been in, I'd estimate 70% of commercial aluminium TIG is done without a pedal in the UK. It just gets in the way. "Aint nobody got time for that"

 

[minimutly]

I use the torch button and slopes. Set to slope up and down to around 25% main current. Slope down is about 3 seconds, slope up maybe 1.5.
There's a mode that a lot of machines have enabled by default, and some have it buried away as a configurable option, called "2T arc restart". This means when you let off the button in 2T, it slopes down, but if you press and hold the button before it's extinguished, it slopes back up. With a bit of button tapping, you can control the heat level pretty accurately, without a pedal in sight.
That's my technique for smaller awkward bits anyway. Long seams it doesn't matter as once you get going your amps should be pretty steady, I'd weld in 4T so I wouldn't have to hold the button all the time.

As for main current, you go with whatever it takes to puddle in a few seconds generally. If it won't puddle then you need more amps. When a workpiece is large, and stone cold, you have to bump the amps way up. and after it warms up a bit, drop the set amps a bit.

You maybe don't realise, but going on the workshops I've been in, I'd estimate 70% of commercial aluminium TIG is done without a pedal in the UK. It just gets in the way. "Aint nobody got time for that"

"70% of commercial tig" this is my point - proffessionals that are doing this all the time, they can 2t and 4t without thinking about it - a million miles from amateur learners, but where we'd all like to get to. A pedal made all the difference to me, and I'm an amateur learner. 4t? Beyond my brain to grasp it when all the other stuff needs sorting at the same time. I did use 2t quite succsessfully though, but I still go for the pedal if I can.

 

[Munkul]

"70% of commercial tig" this is my point - proffessionals that are doing this all the time, they can 2t and 4t without thinking about it - a million miles from amateur learners, but where we'd all like to get to. A pedal made all the difference to me, and I'm an amateur learner. 4t? Beyond my brain to grasp it when all the other stuff needs sorting at the same time. I did use 2t quite succsessfully though, but I still go for the pedal if I can.

Bear in mind, I'm a wannabe professional, not a real pro

 

[Richiew]

If you can weld hot and fast and keep the heat down you won't need a pedal. For the rest of us deficient of talent or practice a pedal is helpful. It can at least prevent you ruining a part with too much heat soak. I agree, pros wont need one most of the time. It is a helpful crutch for the rest of us that only weld occasionally.

 

[Tangledfeet]

Bear in mind, I'm a wannabe professional, not a real pro

Shouldn't you be polishing your shoes, shaving, washing your hair, digging out the suit, ironing a shirt and getting your Mrs to choose a suitable tie this morning? ;-)