Mig welding aluminium

[GraemeVW]

I have had a bit more of a play at welding aluminium.
My set up is not ideal, but I'm not really after changing any equipment.
I only ever have a small need to stick a couple of bits of aluminium together, which I can achieve, but it's not pretty. Once filed back it's done it's job though. But thought I'd see what I could do to improve things a bit.

It's a Clarke 150en turbo or whatever.
Teflon liner, can't remember if wire is 0.8 or 0.6. Using disposable pure argon.
I'm wire brushing with stainless steel brush before hand and pre heating a bit with map gas torch.
As I say, it does stick aluminium together but wondered if I could get a better result. The issues are...
I'm running the welder at about half power, it seems to need that. It's probably on about half wire speed too. But this gives a very raised weld. It seems to be about the only setting that works though. Turn wire speed down and it just burns back. Turn power down to match a lower wire speed and it just splitters and spits.
It's not the most controllable weld!
I'm reasonably ok at welding steel. I have a better welder for that though but I used to use this Clarke for steel.
It just feels like everything is happening too fast, but trying to turn stuff down just results in it not really working. There is one setting that works, ish, but is just a flurry of wire spark and splatter.
The weld is sooty after. Wire brushes straight off after, but didn't know if that's significant.

I'll be honest, I'm surprised this set up works AT ALL, so I'm happy I can at least melt bits of aluminium together, even if it does require alot of clean up after. I certainly wouldn't rely on it for strength though, but I have no need for that.

I know what folk are going to say, get a tig, or at least get a spool gun. But I really don't need to set up properly for welding aluminium. I just had this old Clarke left over after upgrading to an eland, and figured I'd see what's possible.

If this is as good as this set up gets, then so be it. But if I can tweak anything, or learn better technique, then great.

 

[8ob]

I know what folk are going to say, get a tig, or at least get a spool gun. But I really don't need to set up properly for welding aluminium. I just had this old Clarke left over after upgrading to an eland, and figured I'd see what's possible.

If this is as good as this set up gets, then so be it. But if I can tweak anything, or learn better technique, then great.

Wrong, they may say post up pics or it didn't happen

Bob

 

[GraemeVW]

Wrong, they may say post up pics or it didn't happen

Bob

Yeah, true.
After I'd done the weld I thought, I need to ask some advice. Then I though, I should take a pic. Then I though, it's really embarrassing though!
So I filed it back to see If I'd done enough for what's needed and the two pieces are properly fused together.

I need to do some more in the next week though so I'll take pics then.

To give an idea of the scale of what I usually need to do, I just did about 4" of weld, and I probably need to do another 2". Then I won't touch it again for years. Hence me really not wanting to set up properly for it yet.


Edit, actually, I'll do a little test piece tomorrow and take pics. Then you can all laugh.

I can weld, honest!! Just not aluminium

 

[GraemeVW]

Oh, and also, argon. I'm sure it's making feel a little rough. Maybe i just dont like the smell. I can weld indoors all day doing steel, but 10 mins welding aluminium and it makes me feel like i have a very minor cold, or like I've been in chlorine swimming.

 

[wyn]

I bought a clarke 150 as my first mig with the intention to be welding lots of aluminium stuff.

There was no hope of that!
I think you would need the power on max.

I've done some 2mm aluminium with a 180 amp kemppi turned up flat out and that's about it's max.

 

[GraemeVW]

I bought a clarke 150 as my first mig with the intention to be welding lots of aluminium stuff.

There was no hope of that!
I think you would need the power on max.

I've done some 2mm aluminium with a 180 amp kemppi turned up flat out and that's about it's max.

It does seem like it needs more power, and it has more to give. But it seems like it won't quite get the balance of power to wire feed right.
It seems like the wire feed always needs to be too fast for any given power setting or it just burns back to the tip.
Maybe if I pre heat alot more so it needs a little less power?

Today I was welding the end of a 16mm square bar to the face of a 5mm flat bar. I V'd it out and preheated the 16mm bar more. I still blew the end corner of the 5mm flat bar away though so im sure there is enough power in the set up.

I'm really not after getting this set up to work perfectly, just wondering if anything can be done to improve the 'Just about working' result in getting.

 

[tom2207]

polarity ? have you messed with it ? was the machine set up for gas less before hand .... just thinking out loud here

 

[wyn]

Pre-heat could well help.

The corner would probably melt away pretty quickly.

I think even running well it would only weld 1mm sheet together.

 

[GraemeVW]

polarity ?

Hmm. Didn't pay any attention to it.
I pulled some steel wire out if it today before putting the aluminium in so I obviously welded steel with it since I last used it for aluminium. So if I swapped polarity last time, I probably swapped it back.

 

[GraemeVW]

Pre-heat could well help.

The corner would probably melt away pretty quickly.

I think even running well it would only weld 1mm sheet together.

First time I tried it I was building up some broken fins on a motorcycle head. Backed with stainless steel, just built it up from the 3mm wide edge.
Wasn't the most controllable process, but worked and has done 500-700 miles since.

I'd try it on 1mm, but I have a feeling it would be even less controllable.
Material thickness and power doesn't seem to be the issue. Getting the wire feed down for any given power setting seems to be the problem.

 

[tom2207]

First time I tried it I was building up some broken fins on a motorcycle head. Backed with stainless steel, just built it up from the 3mm wide edge.
Wasn't the most controllable process, but worked and has done 500-700 miles since.

I'd try it on 1mm, but I have a feeling it would be even less controllable.
Material thickness and power doesn't seem to be the issue. Getting the wire feed down for any given power setting seems to be the problem.

are you pushing or pulling ,,, I push ,,, and a longer stickout helps too ..

 

[carbon]

The torch needs to be positive for welding aluminium but ideally capable of spray transfer. Ive never tried welding aluminium with this size machine but the torch angle ideally wants to be closer to 90 degrees rather than the angle for steel.

 

[GraemeVW]

are you pushing or pulling ,,, I push ,,, and a longer stickout helps too ..

I tried both. I haven't done enough to have come up with a preference. Probably mostly push though.
I'll try more stickout. I'm chucking gas at it too.

I'm pretty much trying to treat it just like welding steel, but it doesn't seem to respond like that.

 

[GraemeVW]

The torch needs to be positive for welding aluminium but ideally capable of spray transfer. Ive never tried welding aluminium with this size machine but the torch angle ideally wants to be closer to 90 degrees rather than the angle for steel.

Ok, I'll try that too. Thanks.
I think I'll try turning up power more too. It's just wire feed feels so fast compared to welding steel.
The whole process just feels rushed and out of control.

1.2mm mild steel is my comfort zone though.

Edit... I'm almost certain it will be on positive torch as the last word in it was steel, and I've never used flux cored.

 

[tom2207]

I tried both. I haven't done enough to have come up with a preference. Probably mostly push though.
I'll try more stickout. I'm chucking gas at it too.

I'm pretty much trying to treat it just like welding steel, but it doesn't seem to respond like that.

no its basically running in spray transfer , more stand off , more heat and more speed , Im surprised you have it working at all , Im not an expert at it by a long shot , Id have dug the tig out long ago.

 

[GraemeVW]

no its basically running in spray transfer , more stand off , more heat and more speed , Im surprised you have it working at all , Im not an expert at it by a long shot , Id have dug the tig out long ago.

I'm surprised too!

This old Clarke was never that great on steel! It used to birdsnest wire all the time, no matter what liner was in it! I'm amazed it feeds aluminium wire but it's never had a single problem, even when it's burnt back and stuck to the tip!

 

[GraemeVW]

are you pushing or pulling ,,, I push ,,, and a longer stickout helps too ..

Quoting this again as I've just read that you get soot when you pull. I was trying both to see which worked, maybe it was the pulled bits that were sooting up on me.

 

[malcolm]

Worth pictures of a test piece. I did some alu bodywork on an Aston Martin with a Clarke 155 once. Here it is: https://www.aston-v8.co.uk/aluminium-body.htm It's not ideal but it was possible.

Also I wrote down what I learned: https://www.mig-welding.co.uk/aluminium-welding.htm

 

[GraemeVW]

Worth pictures of a test piece. I did some alu bodywork on an Aston Martin with a Clarke 155 once. It's not ideal but it was possible.

Yes, I'll take some, just for curiosity.

I'm never going to get this process down properly with this set up, and I'm fine with that.
It will do ugly welds that ultimately lack full penetration, but they file back and leave me with 2 pieces fused together, and that's better than nothing.

Got some tips to work with now so I'm itching to try again.

I suspect on bodywork gauge I'd struggle not to just blow holes, even though steel bodywork is 95% of all the welding I've ever done.

 

[hotponyshoes]

Ok, I'll try that too. Thanks.
I think I'll try turning up power more too. It's just wire feed feels so fast compared to welding steel.
The whole process just feels rushed and out of control.

1.2mm mild steel is my comfort zone though.

Edit... I'm almost certain it will be on positive torch as the last word in it was steel, and I've never used flux cored.

It does feel rushed and out of control.
I think the general consensus is you want pulse mig for anything below 5mm thicknesses, Spray transfer above that.

Travel/welding speed is at least 50% more than steel, if not 75%-100% more!

No need for preheat once you are going that I have found. Does make the starts a bit nicer but 5x material thickness or so in and there should be plenty of heat getting into it anyway. So much so that you will probably want/need to use a backing plate on thinner stuff.

Regarding feeling funny after using the argon, It might not be the argon (that's inert after all)
I don't have any problems using pure argon for tig for hours on end. When aluminium mig welding I use an air fed mask as if I don't have woken up a few times in the night feeling like I can't breath with a sort of metallic taste/smell in my mouth/nose.
I'm not sure if it's caused by the actual welding or the cutting/grinding/prep work?
I 'think' it's the welding itself as I cut/ground alloy before with no problems but it could just be some sort of intolerance I have developed?