Poorly done solder work will fail just as poorly done plastic filler will. On the other hand, professionally done solder will always last longer than plastic filler, it's just the nature of the beast. Any Plastic, catalyzed or not, is always shrinking, whereas 30/70 tin lead alloy does not once it has cooled. ---John
Yeah bud, it's all "bondo". Just like vaseline, kleenex, bandaids... You're right, prep is the whole world on this topic. Preservation too. Why work your ass off only to let water and shit in from behind. I don't care for anything but lead in areas like rocker panels or roof pillars. I went to a GM expo once at their Milford proving grounds and they had some displays. There was car on a vibrator (2 actually, a Vette and a FWD "something") and I was amazed at the amount of movement in these things. There was a strobe light set up to light certain parts of the car in sync with the movements. The Vette instrument panel moved up n down nearly 1/2", maybe more! The roofs and door gaps were changing, steering columns looked loose. It really gave me a clear idea of some what's and why's regarding body flex. You can bend a stick of lead pretty far and bend it back. Take a stick of "Polyester Filler" and try it. SNAP!! Just sayin...
Lead work looks easy to do on the flat but when trying to do it on a car it is much harder. I have seen some nice lead work done but for some reason the acid etching has eaten thru from the back. That acid part goes again my principles of body repair if it can eat it out later. Very thin layer of bondo is my preference these days especially with all the improvements in bondo technology we have now.
Once you learn they basics of lead, It just takes a little practice. Some people just take to it (I did) and others never master that half soft lead thing. As far as acid etch eating through from the back, Im not sure I follow you here. I don't think acid etching itself has much of anything to do with lead work as a regular step. I never acid etched before leading (unless it was pitted with rust) and you would most certainly neutralize it before topcoating anyways. I acid etched my complete 39 Olds coupe (23years ago) one panel at a time but not for leadworking. My car was pretty heavily pitted with rust. Acid etch and then neutralize, then two stage high fill primer. I saw the car a couple years ago, still has my paint on it and it still looks good. *note: Todays plastic filler is a pretty good product, as long as it is not used excessively thick....even then it holds up pretty well.
The Jalopy Journal
