if tig welded, the fit of the parts to be welded will have to be perfect, it will be best to blow argon on the backside of the weld and using copper or aluminum clamped firmly, wherever possible, to control excess heat in the base metal. I will require a very highly skilled welder to get good qualty and will probably be a complete disaster if it is tiged by anyone less. I think about 20 amps or less is all that would be needed. furnace brazing or similar is probably only realistic approach
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