Prime, seam seal, prime again?

[marlinspike]

Just wanted clarification on the order of things. I have de-rusted my project car's replacement door - managed to stand it in a shallow bath of Deox C solution. This leaves me with this (this is the worst bit):

I have prised open the seam and will do a bit more work on the rust. The hole will be cut out and a patch welded in. Then I planned to coat it all with Bilt Hamber Hydrate 80, which is a rust killer and coater. What's next? Epoxy primer, then seam seal, then primer again? I have some Upol Grey Stripe brushable seam sealer, but wondered if the Puraflex 40 polyurethan tube sealant would be better? I had never heard of using this on cars, but it was recommended in another thread.

So, prime , seam seal, prime again? Any comments welcome.

 

[steveo3002]

id skip the hydrate 80 on clean metal ..leave it bare for a better key on the epoxy

prime it ..make sure its worked into the gaps etc , seam seal then paint

grey strip is good stuff if you want brush on , if you want caulk type then a pu sealer like tiger seal will be good, not heard of your puraflex i suspect its prob the same stuff

 

[richie00boy]

Yeah, the epoxy is a lot better than Hydrate 80. The Puraflex 40 is good.

 

[marlinspike]

Ok thanks, guys. I have been looking online for epoxy primer but it's a bit confusing. I need something you can spray at home, so can't be 2k. The only one I can find seems to be Jotun 80. I thought Lechler made a 1k epoxy primer, but I can't seem to find it now.

 

[Rocketman]

2K epoxy primer isn't as dangerous as 2k top coats and doesn't need a air fed mask - you can actually brush it on to. If you don't do epoxy primer I would use the hydrate 80.

As far as other coats you could use a seam sealer on the seams and stone chip the lot. Finish off with primer and top coats.

 

[marlinspike]

Thanks, Rocketman, I get it now. I will find some epoxy primer for the repaired bits and use Hydrate 80 on bits like the hinges where there has been slight surface rust.

 

[Rocketman]

Another thing worth considering if you will never be able to get to the insides of the cavity you weld up or lap joints use some weld through primer/similar on all the hidden faces. It's about the only thing you can do to give a bit of protection.