I am having difficulties TIG'n my corroded assemblies. These Bravos are about 25 years old and have been repeatedly exposed to salt water. Boat's transom was rotted. I replaced. I have used ss brush to remove corrosion but there maybe too much saltwater deep between aluminum molecules? My TIG is a square-sign wave. I may have to take Bravos to a shop with better machine? However, I don't think it is my TIG's problem. It is the years of soaking in salt water. It is impossible to remove all the salt contamination even with high speed ss wheel and burrs. Therefor a friend recommended "Metal 2 Metal" to build up and smooth out surface. My last two lower gimbal assembly lug areas have to be built up and then surfaced to be flat. This repair will obviously be below salt water line.