TIG Alley

[Dr.Al]

I've been doing a bit of practice this evening on TIG welding Aluminium.

It feels like my flat plate beads are finally getting somewhere:

there was a bit of contamination at the start of the first one of those beads (the top one) and it went all grey and matt part way through but the subsequent two looked quite good. I tapered off at the end and moved the torch back a bit while I was doing it, but there's still a bit of a divot at the end.

It's made an enormous difference to the appearance of my welds switching from 4043 (I think) to 5356 (I think). I'd been really struggling to get good looking beads with 4043 - they just looked blotchy and horrible. 5356 seems much better.

Base metal is (I think) 1050. It's 2 mm thick. The (R-Tech TIG210EXT) welder was set on 90 A (but I don't think I got anywhere near that as I had the foot pedal connected and wasn't pressing hard) with 25% balance, 120 Hz, 30 A start current, 5 A end current and 4 or 5 seconds post flow (I can't remember which). The tungsten was 2% lathanated 2.4 mm sharpened to a blunt point (earlier ones I'd been balling up the tungsten but didn't bother for these). Filler was also 2.4 mm.

While I'm really pleased with the above, my outside corner joints still need a lot of work...

Any and all advice welcome!

 

[M K]

Hi

the bead runs look very good,

An extra dab of filler at the same time as you taper off and end the run will help get rid of the crators

5356 doesn’t wet out as quickly as 4043 so a lot of people find it easier to control the puddle with,

Each have there characteristics

With outside corner joints, the fit up makes a huge difference and you only want the 2 pieces touching with no overlap. Don’t get me wrong you can still do a nice weld if they overlap as sometimes you have no choice but for practice, having proper fit up and placement of the pieces the outside corner joint can be made easier

Also it looks like your far too hot on the outside corner joint, to help try manually lightly pulsing the foot pedal or put a chiller block (an old big of solid square bar) behind the joint to help control the heat soak

if you manually pulse, don’t let the puddle fully freeze, just enough for it to cool

Hope some of that may be of use

Thanks
Marc

 

[Barking Mat]

When I can pay beads like that I'll be a happy man!

Very nice @Dr.Al

 

[Dr.Al]

An extra dab of filler at the same time as you taper off and end the run will help get rid of the crators

I thought I was doing that, but maybe the dab of filler was too early or I needed another one as I tapered down. I'm not working again until Monday so I'm going to try to do a bit of practice every day.

5356 doesn’t wet out as quickly as 4043 so a lot of people find it easier to control the puddle with,

Each have there characteristics

I didn't know that about 5356/4043. I haven't found it that hard to control the puddle with 4043 (although nowhere near as easy as with 5356), I've just been really unhappy with the results afterwards. I'll do a couple of 4043 beads next to some 5356 ones and post a photo - hopefully you'll see what I mean.

I'm not too worried about it at the moment, I've got loads of 5356 filler (albeit only in one size whereas I bought a multi-pack of sizes of 4043), so I've got lots of opportunities to practice with 5356.

With outside corner joints, the fit up makes a huge difference and you only want the 2 pieces touching with no overlap. Don’t get me wrong you can still do a nice weld if they overlap as sometimes you have no choice but for practice, having proper fit up and placement of the pieces the outside corner joint can be made easier

I'll make sure this is spot on for the next few practice runs. Thanks for the advice.

Also it looks like your far too hot on the outside corner joint, to help try manually lightly pulsing the foot pedal or put a chiller block (an old big of solid square bar) behind the joint to help control the heat soak

I'll have a go, although the manual pulsing sounds hard!

if you manually pulse, don’t let the puddle fully freeze, just enough for it to cool

Okay, that's good to know.

Hope some of that may be of use

That's incredibly useful. Thank you for taking the time to give such a lot of useful advice

 

[Dr.Al]

A tiny bit more practice this morning...

This is two beads run on the same bit of aluminium, one after another. First one (top) was done with (Parweld) 5356 filler wire, second was done with (R-Tech) 4043 filler wire, both 2.4 mm filler wire. Material is 2 mm thick, probably 1050.

That's definitely the best 4043 bead I've ever done, but it still has the mottled finish that seems an inevitable feature of the 4043 filler, or is that just me?

Close-up of 5356:

Close-up of 4043:

I then went on to doing an outside corner joint and tacking some more. This is how I get the fit-up as good as I can...

Two sheets (with milled square edges) on my fixture plate:

Edge looks like this:

Tacked (I need more practice at this):

Tacks cleaned:

and the result:

Inside view:

Getting better?

I then went on to tack this up, so I've got 12 more outside corner joints to practice:

This idea is nicked from weldingtipsandtricks on youtube as a good exercise. One one of the cube corners, I've filed a bit of each sheet away to make a vent hole - you can't see this in the picture as it's not one of the top corners.

 

[Barking Mat]

Oh you are having fun.

I want my tig at home!

Nice work mate, looking good!

 

[AndersK]

Looking good.
4043 is prone to get a grayish finish but it's just cosmetic. If you want really shiny beads try some 1070 rods.

 

[Dr.Al]

More progress...

Mounted it with a lump of 416 on top to stop it wobbling around (you can see the vent hole in this shot):

Gave it a thorough wire brush before starting:

Definitely getting better at this:

Close-up (of the best joint - not all were this good):

Just waiting for this lot to cool down before I plug the vent hole:

(Swapped to a bit of 303 as the 416 had one end that wasn't flat enough to sit still and one end with paint on - you can see the effect of sitting it on the painted end on the left-bottom face in that last picture!).

This one is made out of 90 mm (ish) side squares. I've got 6 more of them so I can make another cube that size. I've just acquired 25 square bits (125 × 125 mm) each of 2 mm thick and 1.2 mm thick aluminium, so that should give me plenty more to practise with! The bigger size will also mean I need to move my arm more and feed more rod, so that'll be good practice. I guess I need some smaller filler rod (not 2.4 mm) for the thinner (1.2 mm) sheet though.

 

[Dr.Al]

F...

...iddlesticks.

Ah well, keep practising...

 

[Barking Mat]

Oops.

 

[Barking Mat]

Too much heat or blow back? Or lack of back purge?

 

[Dr.Al]

Too much heat or blow back? Or lack of back purge?

I think it was just too much heat. I was trying to seal the little hole quickly and it got hot fast and dripped. Maybe there was a bit of blow back as well, but I'd guess it's mostly heat. C'est la vie.

It's getting too hot in the workshop now, but I'll have another go tomorrow. I've got enough squares of 2 mm aluminium to make 5 more cubes, so that's 60 outside corner joints and 5 more attempts at sealing the vent hole.

After all that I'll start thinking about inside corner joints, but I think they'll be a lot harder based on the few appalling attempts I've had in the past.

 

[Barking Mat]

All good practice...

 

[addjunkie]

Lots of inside corners, before you put the last face on your cube.

 

[Dr.Al]

I had another go at a cube yesterday (but couldn't be bothered to go on the computer to upload photos).

Similar to the day before:

(they're all different edges). Not perfect, and this was the first time in two cubes (24 edges) where I dipped the tungsten, which has got to be a record for me, so that's a good thing.

Vent hole pre-plugging:

I'm definitely doing something wrong here:

As soon as I light up on the area around the hole, it just feels wrong. I'm not really sure how to explain it, it just seems like the previously welded joints are contaminated or something; it doesn't clean and produce a puddle that I can control, it just goes nasty and then becomes a messy hole.

I'll have another go tomorrow. At least the edges are okay and that's probably way more important than plugging that last hole.

 

[willie.macleod]

I think what you are seeing is a lack of argon shielding - if I understand you don't have another vent hole? If not then the heat from the weld is pushing the air out and the argon away. Try drilling another hole in the middle of the top for the air to escape and see if that helps things.

 

[minimutly]

I think what you are seeing is a lack of argon shielding - if I understand you don't have another vent hole? If not then the heat from the weld is pushing the air out and the argon away. Try drilling another hole in the middle of the top for the air to escape and see if that helps things.

I can do that sometimes - no idea why, makes me want to throw the torch..

Someone on here suggested that of the ally was new, wiped down with acetone, no need to wire brush - I think he was right.

 

[willie.macleod]

I will admit I see lack of argon shielding a bit too often, my problem is I use lift arc and manual valved torch at work and HF start with electrical valve at home.

 

[Dr.Al]

I think what you are seeing is a lack of argon shielding - if I understand you don't have another vent hole? If not then the heat from the weld is pushing the air out and the argon away. Try drilling another hole in the middle of the top for the air to escape and see if that helps things.

Ah, maybe the answer is as simple as this. Yes, I don't have another vent hole. I was copying an idea from this youtube video: he makes it with one small vent hole then lets it cool down and "quickly lights up over the hole to plug it". Irritatingly, that's the one bit he doesn't capture on camera! The idea is that you end up with a completely sealed cube, although there's no particularly good reason why one would need such a thing!

Someone on here suggested that of the ally was new, wiped down with acetone, no need to wire brush - I think he was right.

Yes, I don't always do it. Sometimes I just figure that it can't hurt and too much cleaning/preparation will always be better than not enough. While I'm learning techniques, I want to take as many variables out of the equation.

 

[Richard.]

Pressure blowing back as there is no where for the gases to escape when you try to button it up on last corner.
Drill a tiny hole in one of the faces and it should resolve this
Then dot a bit over the hole when done.