I had to do a lot of repair work on Brampton castings because most of the tubing was unsafe. I fitted stainless adapters to the castings to beef up incredibly weak parts. All TIG welding was high nickel material for joints that are either very hard or for unknown steel assemblies. You can play extra safe by having pure nickel rods like used on cast iron components, but Brampton items are no brittle cast iron anyway. Jake Robbins did the retubing later.
Vic
Vic