i like your plan and as a matter of fact plan on doing exactly that to my truck and here is why.
because when i said "no rust so far" that was total BS. i went outside and washed it down really good and this is what i found besides nine tons of Buff colored overspray: little areas that looked just like oil stains, except when i washed and rubbed them to remove them they did not remove: because it is rust spots starting to come thru. and they are everywhere! my plan is not to reprimer tho but just hit it with some Rust Mort, let dry then do what you are doing with the black john deer paint or whatever. i would spray it if i didnt have so many parts i dont want painted, air pollution or not. i have to do this because i want to get top dollar for it and it's for sale so....
i would blame it on the red oxide used not being as high quality like the sign shops, like i thought it was. also, because it was sprayed, i think even with two coats, it wasn't as thick as a couple brushed coats would have been. that and the fact that the frame paint was just generic crap that the paint shop had on hand at the time. Your plan to use two part paint would have to be better than just the john deer stuff i plan on using. but i dont plan on having this truck for long, unfortunately, (it's my 'baby') as i said.
anyway, i like your plan again, think it will hold up longer than mine did. especially with an epoxy primer (like my buff job) instead of red oxide. red oxide is pretty damned good stuff. i have seen it bead up water like crazy in the rain (at least the stuff my sign shop used), however it isn't spozed to be waterproof like epoxy or urethane primer is (which is why i painted my truck with urethane). as far as boxing the frame, i dont remember what you said it looked like already, if its almost all boxed already or not, so i got no opinion on doing that and making it airtight. i know when exposed to air, water will dry out. however, when exposed to air it is also exposed to mud, which retains moisture and makes for rust so.... don't know what to tell you. i've heard water will get sucked into anywhere, and that is probably why you want to coat the inside with oil, so that all sounds good. but i'm not a physicist.
Last edited by bullheimer; 04-12-2012 at 02:15 PM.