Tips on Welding alluminium please

[Brett]

hi all,

i have recently applied for an apprenticeship at Austalships in Western Australia building aluminium vessels,

i was wondering since there are so many welders here there would be a chance some have welded aluminuim and would be able to give me some tips/pointers,

it would be much appreciated if someone would be willing to tell me something,

thanks

from brett aka pcII75

[Mr Smith]

TIG's yer best bet. Dunno how much you know about TIG, but it's like oxy, in that you use a filler rod.
My old man knows a fair bit - I'll ask him next time I see him. (In fact, he worked for Austal, when I was a little fellow)

[Stu in Tokyo]

I worked for a short time welding aluminium with a spool gun MIG, not that hard to do, but it was REALLY basic stuff, nothing complex, production welding.

I know if you want to get into it, and do it right, there can be some preheating involved, if you weld at room temp, the aluminum sucks the heat away so fast, that you often get cracking.

Sorry I don't know that much about it, but maybe the Hobart Welding Forum would be a good place to ask (I hope I'm not talking out of school mentioning another forum).

Good luck!

[Thomas Dean]

There are 20,000 grades of aluminium! Alum. has an oxcide that needs to be buffed off, use a power wire brush.The preheating mentioned above is a must when welding 1/2" and above. (you'll be longer welding it the it took you to grow. ) TIG is usually preferred but there are places (truck trailer manufactures to name one) that use strickly MIG. depends mostly on what type of alum you are using and what the sevice is. We use TIG on our alum piping and plate work. T61 alum pipe uses 5356 wire, 3003 alum plate uses 4340 wire. when we weld flanges (3003 plate) to pipe (T61) you have to use 5356 wire. Use ZIRCONIA tungsten when TIG welding alum, and the heavier the material the larger the tungsten. You don't point the tungsten either, it should have a nice round ball on the end. AC current, Argon purge. Now, if you are going to apprentice at this shop, they will teach you how to weld the stuff, after all that is what an apprentice is, a STUDENT. Good luck.

P.S. I didn't say much about the MIG process because we don't use it here but it is good for the right applications, as is anything else. (the purge gas is best if you use a tri-mix tho. 92-6-2, argon, helium, and Oxy....best as I remember....)

[Brett]

thanks folks, very interesting.

they use wire feed/MIG welders there, there is a afew TIG welders around the place, i wouldnt mind learning to use one of them,

they use Argon gas, i know that much... ive only used a little gassless MIG my dad owns,

have no idea bout the different wires, also had no idea of the grades of alluminuim, thanks Thomas

thanks Stu, didnt know you had to pre heat for welds...

i know they will teach me all this in there,, i just dont want to hurt my self, others or damage the equipment...

thanks

from brett aka pcII75

[Ten Hammers]

Brett, I will say this. I ain't no loomnum welder. I would say that you have an excellent chance to learn if you get hired. I will also say that them boys will teach you their way fairly quick if they want you to learn. I also suspect that there will be one or 2 in the bunch that will be awful sharp compared to the others. I weld steel ( and a bit of stainless occasionally ). I hope to learn some aluminium someday just for home shop use. good luck.

[Dave Shepard]

When you get aluminum TIG welding down pat it is, in my opinion, one of the best welding experiences out there. It can be very frustrating when you are just starting out. You need patience and a steady hand. One of the problems with welding aluminum is that aluminum oxides melting point is about three times that of aluminum, so you have to get rid of it, either chemically or mechnically, before you weld. Keep everyting as clean as possible, not only the workpiece, but the work area and the consumables as well. I will wipe down the filler rod and work area with an aluminum cleaner before I try to weld. Get some advice from the people who are going to train you on cleaners, the wrong stuff can create potentially harmful fumes when you weld them.
Walking that little silver puddle around wherever you want it is a great feeling!


Dave