This alloy is especially used by aluminum window manufacturers to solder mitered joints without the use of flux. Ideal for sealing holes in aluminum boats, leaders, gutters, siding, and castings such as outboard motor/chainsaw/motorcycle castings. Unexcelled for high strength and long service without the problem of galvanic action between base metal and solder.
Procedure
Aluminum surfaces to be soldered must be clean and free of all dirt, grease, and oxides. Sections heavier than 1/8" (3.2mm) should be beveled 75 to 90 degrees. Jigs and clamps will keep parts in alignment. Use a carburizing flame to heat base metal sufficiently to melt the rod when rubbed on the surface. The rubbing action is required to give a good bond. Do not apply flame to the alloy but allow the heat from the base metal to melt the solder. All-State No. 55 Rubbon is made stiff enough to break through the normal oxides found on clean aluminum. Tinning action may be improved by wire brushing through the molten solder.