Just read the tech library article on treating rusted body panels and seek advice. I have been using cold galvanizing compound on the back of the new panels I have welded in and found that it does not burn away from the welding heat. I painted over the weld on the inside of the esposed panels and then sprayed rubberized undercoating to further protect and deaden sound.
Now the tough part, how do I treat the weld joint (mig) on the inside of the closed panels (rockers and lower door post legs on a 71 chev pickup)? The unprotected mig weld appears to rust very fast on my test panels which were soaked in salt water for two days and then just left in the shop. The welds which were smothed and coated with cold galvanizing have shown no sign of rust in over 6 months and the areas I coated with rust encapuslator and POR15 are fine. I am unsure if the rust encapsulator can be sprayed so that coverage is insured and the cold galvazaning is way too thick to spray. Is there a product you suggest that will last or should I just remove the plugs and spray oil in periodically. The truck will not be driven in winter but I am concerned about how fast I see rust forming on the exposed welds on my test panels. thanks bob