Hi 357max,
You can say that again! OFW Aluminum is prolly the toughest welding challenge I've ever faced next to trying to weld 1/2" diameter EMT (conduit) using SMAW :) - but hey, that's what makes it so interesting.
I've read that Al SMAW electrodes will work well for OFW, but given that I've only seen them in 1/8" or larger sizes, I think it would be too hard to use them on thin stuff. Plus, they're pretty pricy for an electrode anyhow.
If I saw Cobalt Blue lenses in a welding shop, I'd buy up every last one in stock! I had a chance once to look through a pretty thick piece of a cobalt blue lense - the type chemists use to detect sodium with - while pointing a torch directly at a piece of aluminum fluxed with borax and it was incredible how well it filtered out all of the flare. But, I've been told that they were taken off the market for safety reasons. Oh well.
Thanks for the info. I'll have to see if I can find some of the brazing fluxes from MG.
Chris Maier