Cold Tig torch

[Richard.]

I've have just received back my beloved machine. And I went to use it last night which reminded me of a question I wanted to ask weeks ago.
The 1st couple of runs on aluminium are always a little on the scabby side with any flavour of filler.
But the 3rd 4th and so on are perfect. The temp of the plate makes no difference neither dose the cleanliness. I think it might be the fact that the torch has no heat in it to start with. Its water cooled and the cooler runs consistently. I cannot think of any thing else as it becomes perfect as soon as the torch gets a little temp in it.
I guess the question I'm asking is can a torch be too cold to weld Ali with.

 

[PhillipM]

Don't know what the answer is but our Kemppi mig does the same.

 

[wheresmejumper]

Slight gas leak that when the torch heats up and expands, said leak disappears?

 

[Richard.]

Slight gas leak that when the torch heats up and expands, said leak disappears?

Where could it be leaking from that expansion could stop. As far as I can tell the only part of the torch that heats up is the cup its self as the cooling is very efficient and keeps the rest of the torch cold. I had another go half hour ago with 4043 and the first run had that typical scaly finish on it that sometimes happens with the 5% silicon the second improved slightly and by time I got to the 4th it was super shiny.
The 5356 does it but with a less scaly appearance having no silicon but it's still weird. It does not cause a problem as I just do a couple of runs before a job I'd just be interested to know who can pin point the problem.
I'll check the unions in the torch handle for a leak as that's a very good suggestion. Cheers.