You're not the Tom C from Bristol I thought you were! He has a BMW with an M42 engine, but somewhat non standard.
I'll go away now, know nothing about TIG and aluminium!
Ahh that's fine!! Don't see too many modded bmws around here except the chavved up halfords jobbies!
come on then give us a clue what engine is it you never know someone reading may have one sat there doing nothing
I will call up at some point to see about one piston but I think it's unlikely. But is welding it an option worst comes to worst
No chance, piston will be taking heat above welding temp.
It's a gpm piston. There's a set of four on eBay ATM. But I'd still have this set doing nothing even if I did buy them. So I could do with some advice, someone most know. If not I'll give them a shot with sone high content silicon rods. And get a block machined to accept them. They owe me nothing so I may as well give it a bash
If the pistons get above welding temperature in an Imp surely they will melt anyway or am I not understanding something
They do, but only for a fraction of a second during the power stroke, then they have chance to cool off before the next combustion event.
However, I still wouldn't weld a piston, it's impossible to determine how it would behave afterwards, but the prospect would be failure which would probably take the engine with it.