Etch primer vs Zinc Primer

[FrankM83]

Hi all, just shot blasted the chassis of the van as I realised that was the ebst way to get all the areas done, now the van is awaiting spray my sprayer and friend of mine is saying it would be best to etch prime the chassis whilts I think it would be best to paint it with sinc primer what do you think? I'm planning to use the van regularly though not on rainy days

[Alec]

Hello Frank,

the idea of etch primer is to give better adhesion to the subsequent paint layers to prolong durability. I don't know if zinc primer is the right way to go?

Alec

[alainmoran]

surely zinc primer would give just as good adhesion (especially to something as rough as a shot-blast finish) but also give a layer of electrochemical protection?

Me I'm going with a rust-converting primer, followed by high-zinc primer, followed by a light coloured enamel topcoat (enamel so that it doesnt chip so easily, and light coloured so that I can see any rust-spots developing before they become holes)

[flying]

etch primmer will give alot thicker/stronger coat than zinc primmer...and etch is for bare metal

[bigginger]

Etch doesn't give any protection from water
ac

[chickenjohn]

If they have just shot blasted all the rust off, and they have the facillity I would get it etch primed straight away before rust starts again- then apply a water proof top coat- such as chassis black, 2-pack, cellulose, which ever you prefer. As Big G said, primer is not waterproof.

If you shot blasted it yourself and would have to take it somewhere to be etch primed, then I would just Zinc prime it yourself (to minimise the risk of the chassis re- rusting). I think once the rust has been removed its more vital to protect the clean steel ASAP. Time here is more important than the method used.

[MoggyTech]

Better still for chassis is epoxy primer.

[bigginger]

...and etch primer will deteriorate fast unless painted over.
a