Welding aluminum with a mig is a real pain n the arse tig is the way on that plus then you can weld stainless with it as well just need a bottle of 100% argon :-)
Since this site has assisted me in realizing several dreams, Welding Aloominum has always been one of them and I'd better start learning. Someone give me the absolute most difficult way and I'll try that first. hahahaha
OK, I actually am a Profesional Welder & weld repair sales engineer. (High end markets like Aerospace, Powergen & Nuclear)
I didn't go through all the full pages. But I did read the TS's post, GMAW (Mig/Mag) welding is pretty commonly done with out shielding, instead of a solid wire a flux core wire is being used..... GMAW with shielding gas is usualy only done indoors and flux core outdoors/ when proper schielding gasses are to expensive/ rare (Like africa)
I sure wouldn't mind awnsering any questions the best to my knowledge....
Don't shoot the messenger!
Alloy welding is on my mind, at some point I need to get a gearbox to fit the 1UZ and stuff it in a vehicle.
What sort of solutions are the big companies using, and what's the best 'bang per buck'?
C.
A cheap chinese tig setup and either a couple of hours one on one with a pro or do a night class. I doubt investing in learning to tig would ever be a wasted skill.
It could be migged but id imagine it's making things difficult for yourself and would require alot of joint prep and even then a hobby mig may not have the guts
I had been told for years that I could weld Aluminum with my welder. I'm not trying it any time soon, I have to read & learn more.
I don't make any real money from the things I weld, so to invest in a TIG just doesn't make sense right now. I had previously taken my Alloy stuff to a buddy that owns a TIG. Everything he's ever welded in Aluminum for me, has fallen apart. I stopped taking stuff to him and I just buy a new one (whatever is cracked or broken) because I have yet to see an aluminum repair actually hold together under use. Motorcycle parts in particular.
If I learn to do it myself, the only person to blame when it fails, is me.
The thing is, are you going to weld cast alloy or wrought alloys, Cast alloys usually contain Zink and is very hard to weld. If you use 5000 or 6000 series aluminium you're good.Originally Posted by cdwood2010
Now the difficulty with welding alumnium in general is that the oxide layer it forms has higher heat resistance than the base alloy itself. So that's why AC or DC Variable Pulse is required for a decent Full penetration aluminium weld... they have a so called oxide cleaning ability, the pulses change so many times that the oxide gets broken down. something regular DC welding doesn't do so. Anyway, always make sure you have decent filler material, there are many rubbish wires out there, so especially when you're not very experianced make sure you use a Decent Brand and wire that goes with your Material..... And always brush the oxide of as good as possible (both sides if possible)
Don't shoot the messenger!
^^^^^ he's not wrong watch out for mag alloys they can quite literally burst in to flames, in general i recommend a 4043 filler as it melts and flows very well, cast alloy can be a bitch depending on the quality as the impurities can cause a real headache in trying to form a weld pool, porosity can also be an issue, i will often run dry passes (without filler) to pull the contamination to the surface and grind em off so i can get a decent pool and bead going, use a stainless steel brush for cleaning your workpiece, never use this stainless brush on anything else to avoid contamination (I keep a zirconium flapper disc and a stainless brush specifically for cleaning aluminium alloy very seperate from anything else) another issue you will face when tig welding cast alloy on cars is that the part has usually been in contact with oil for a long time and of course this will soak into the pores, again dry passes and degreaser can help with this, avoid using large weaves on aluminium (both mig and tig) as the toes usually cool faster then the middle and tends to pull the middle apart and cause cracking, stacking beads is the way to go if you need to fill a large area just a heads up as well to buy a hobby weld bottle of pure argon for mig (on aluminium) or tig is very expensive, about £90 for a refill of a 20l bottle @ 200 bar (plus whatever deposit u need to pay tho this is refundable) that gives you 4000l of gas for £90 and at say ca 10-12l a minute this will give you roughly 5.5h of welding time now I pay £7.50 a month rental + £38 for a refill on a 50 l bottle @230 bar which is 11500 l or nearly 16h of welding now over a year the rental option costs me £128 for 11500 litres and the hobby weld for the equivelant would cost me £258 obviously I do alot of welding so for me it is very much worth it as i was going through a 20l bottle every 6 months before i switched! its worth working out how often you are going to use the argon to decide whether a hobby weld or rental bottle is going to give you the best value, i have a friend with contacts in the bar trade so i have sourced a 10l bottle of c02 at 50 bar, and a refill is only about £4 now ive used pure co2 on the mig for steel but it is messy, an argon co2 mix is much cleaner (pure argon is not recommended for steel with mig as it doesnt give the best weld profile or penetration) but rather than pay more monthly rental for another bottle of argon co2 mix (commonly referred to as argoshield tho techically some brands contain a little o2 also) im gonna run the argon and co2 from 2 seperate regulator/flowmeters and just mix em for the mig,will save a fortune!
I had a go at mig welding stainless exhaust pipe today as i need to tack a bike exhaust together.
I got some 0.8mm stainless wire and a disposable bottle of argon gas from machine mart. I used a knotted wheel in a grinder to clean the pipe.
I found i needed my welder on max settings and the wire speed quite high to be able to tack stuff together. I also ran some individual beads on the scrap pipe and found i was getting alot of build up on the inside but not much on the outside i assume this is because the settings are so high but with the power turned down i struggled to get penetration i didn't play around too much as i just wanted to get the job done. I did find you can hold a weld pool a lot longer with stainless before it blows through i may have a proper play and put some pictures up at some point not that i plan on making anything in stainless anyway
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