04-02-2013, 12:08 PM
From my experience silver solder will bond to any steel I've used, mild steel is fine. If you mean brazing the same applies. Could you make an interference fit, then heat the arm and shrink it on. If not allow 2 or 3 thou gap for the solder to wick into the joint.
Free advice is worth exactly what you payed for it.
Greg
Greg