I need a 16mm T (I'll cut the stuff off an existing T) welding onto my bottom coolant pipe, which is 1.5mm wall aluminium..

The T itself is "alloy" and the larger pipe has been annodised.

Seeing as "alloy" isn't exactly explicit as to its composition, is this possible?

Also, given that the larger pipe has been annodised is this going to need some preparation before tig'ing?

Or would I be better off with chemical metal?

Pictures below of the pieces concerned.




ta
Chris.

Take it to someone who does tig welding. They will quickly tell you if it is ok to weld.
The anodising will need to be ground off to enable the welding.

DEpending on how thick the anodising is (compared to how thick the metal is and hence how many volts youre giving it i spose), you *might* not need to grind it clean, as the AC TIG process literally ejects the oxide coating off the metal anyway (thats what that flaky scaly crap is that you see when tigging).

However, like i say, if its had a really thich anodise, it may need to be taken off first.

Its worth noting that Ally is so reactive that it is always oxidised on the surface. A new oxide coatgin starts forming the absolute microsecond that the pure metal is exposed to oxygen. Further oxidation is stopped by the fact that the oxide layer sticks like poo to a blanket (unlike Ferrous rust).

Ed.
P.S. Sorry, not trying to be an arse, just waffling cos someone somewhere might care...!