On Sun, 22 Jan 2006 02:08:53 -0500, Brent Philion
wrote:

Compared to TIG how hard is OA welding of aluminum

I find it easier, but then I've got a fair bit of OA experience with
steel and I'm a complete numpty with TIG.

One thing I did find is that the aluminium alloy affected things.
Magnesium alloys (about 15% Mg) in vehicle or aircraft sheetmetal was no
problem to work, purer aluminium didn't give me such good results. Welds
seemed structurally OK, but never looked as neat.

Tool up with the right fluxes and go to it for some practice. These
things are fairly easily available, but the English flux for 15% Mg is
obviously the best stuff - if only for the name "Hari-Kiri No. 2" !
(read the Landrover service manual).

A word on fluxes though - these things are horribly toxic when heated,
and their vapours. I'd been using them for years, but I blanched when I
found out just what was in them afterwards. Now I'm a _lot_ more careful
about ventilation than I used to be.