[rotorwrench]

I still gas weld aluminum but I would bolt it up to a jig or a manifold before the attempt. Gas welding is more of a brazzing process but without the brass. Filler rod & flux is available through multiple sources but there are different melting points for different alloys. This is where it is important to know the process and some of the metallurgy of it. Cast is full of all sorts of crap that can pollute the weldment so the type of alloy is not as critical as other aluminum materials. Using a flux with the filler can help with it but every different part is a new challenge. No telling what was in the mix back in the early 1930s.