Posted by David Sherman on Thursday, December 06, 2001 at 11:09PM :
In Reply to: Re: Rust prevention posted by ranglin on Wednesday, December 05, 2001 at 9:41AM :
Shortly after I got my rusty M37 a friend gave me some fancy 3-part catlyzed strontium chromate epoxy primer like they use on airplanes. I mixed the stuff up and brushed it liberally all over the rusty parts, thinking "anything's better than more rust and I can repaint it later". It soaked in great, dried hard, and I figured I was set. I sprayed some OD green over most of the primer because it was an ugly bright yellow, but plenty of the primer was left exposed. Within a year it was chalking and falling off everywhere it was exposed to direct sunlight. I asked my friend about it and he said that epoxy primer has to be top-coated with something that blocks UV or it will disintegrate. Since then, I've just used rustoleum red oxide primer on everything that I'm not ready to do a good job on yet but I want it to stop rusting. Now and then I come across some old red lead primer and it works real well too.