spraying the bottom half and keeping the rust at bay

[andyv]

Sorry if this has come up time and again. I want to spray the bottom half of my camper in cellulose.

Two years back I ground back the sills and lower arches to bare metal, gave it some brush on Jenolite, then sprayed over in regular cellulose grey primer and then top coat. Apart from the colour blend not being too good, it started to rust again quite quickly.

I did the top half last winter, taking windows out and treating the rust with POR15 then spaying over the top. I think this has worked much better, but all the treated bits are hidden by the rubber window seals.

Would it be suitable to apply POR15 to the lower extremities prone to rusting then cellulose over the lot. How about other products such as non isocyanate epoxy primer? POR15 from what I've read prefers a rough surface to adhere to so would this be a good choice on cleaned up bare metal?

 

[vdubz]

I would try to remove as much of the rust as possible (sanding, blasting, grinding,etc..) instead of trying to seal it. Once all your metal is cleaned up as best a possible you really want to be using an epoxy primer, Jotun epoxy is good and i think its iso free?

 

[steveo3002]

in my opinion por15 doesnt live up to the claims

grind /sand /wire wheel as much rust as you can , then a good primer like an epoxy if not some zinc primer then your top coat

 

[bigbadbugga]

POR15 is rubbish unless you adhere to all the prep religiously, and even then it's a bit hit and miss.

Bare metal it and use some epoxy primer as has already been suggested, then when the primer has cured you can give it a light rub down to key it and topcoat it with regular primer and topcoat.

 

[andyv]

Thanks folks. I will go out and get some epoxy primer. I'm assuming I won't have to paint every thing with it, just the bare metal?

 

[steveo3002]

yeah just the bare metal , or if its alot of spots n patches then it make sense to blow over the whole lower panel up to the moldings or whatever