Bronze smoke stack casting for a Coles American La France fire engine had this big gas pocket flaw.
Milled out a pocket that got rid of most of it and used small burr and cleaned the deeper pockets.
Made a plug from some bearing bronze that looked like a color match. Tried for a good fit at top mating surface and loose fit below for more room for the silver solder.
Stacked some fire bricks and some ceramic fiber for a roof. Used a home made propane torch to preheat and then a oxy-acetylene torch for doing the silver brazing.
Plug silver soldered (brazed) in.
Put in lathe and re-machined radius. Looks like it might be OK.
Milled out a pocket that got rid of most of it and used small burr and cleaned the deeper pockets.
Made a plug from some bearing bronze that looked like a color match. Tried for a good fit at top mating surface and loose fit below for more room for the silver solder.
Stacked some fire bricks and some ceramic fiber for a roof. Used a home made propane torch to preheat and then a oxy-acetylene torch for doing the silver brazing.
Plug silver soldered (brazed) in.
Put in lathe and re-machined radius. Looks like it might be OK.