Etch priming bodywork

Hi all,

I'm just about to start painting the first bits of bodywork for my defender rebuild. I've given it a thorough sanding with 180 and 600 grit paper so it's now ready for primer. The problem I've got is I've gone through to bare metal in a lot of places and I'm not sure of the best practice for applying etch primer around existing paintwork as I can find a definitive answer on whether it will react with the old paint. Do I need to dab it on where I've gone through or can I just go over all the old paint? It's a 2k etch primer which I will be applying with a spray gun.

Thanks

Albert

When I had to replace my rear door I did the usual prep, and used a 2K primer all over with no problems... I was only using cans as it was just one panel... if in doubt try a small patch/panel of primer on the old paint before you commit to the whole vehicle.

Ive just painted my mk2 escort took it back like you did some filler, the paint shop advised me to etch, then high build primer and dust in black and flat off.







Then the top coat when your happy with the high build,

We did not use 2k etch primer but did use 2k high build and used a spat gun

The Gribbin said:

When I had to replace my rear door I did the usual prep, and used a 2K primer all over with no problems... I was only using cans as it was just one panel... if in doubt try a small patch/panel of primer on the old paint before you commit to the whole vehicle.

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2k primer from a rattle can???

2k primer is not known for reacting. It is the thinners you mix in that will eat into whatever is below. If the panel is generally already painted then just get the 2k primer on, don't go mad, you don't need a lot of thinner in 2k, only 10 - 15% to help it exit the gun. If you spray celly it tends to react with what's below because it's 50% thinners.

Discokids said:

2k primer from a rattle can???

Click to expand...

Yeah you push in a button on the bottom of the can and it releases the hardener into the paint and then you have a certain amount of time to use it in

This I've GOT to see.

If you are etch priming alloy it needs to be flatted to present a new surface cleaned and the primer applied within half an hour to prevent oxidation setting in.

Thanks for all the advice, I've already painted multiple parts however they were all bare metal and I'm happy with the results I'm getting with the primer, metallic base coats and laquer. It's just now I'm in unfamiliar territory respraying old bodywork.

The only answer I really need is will the etch primer tear off the old paint so I know whether I'll have to spend hours dabbing it onto all the little exposed areas or will it be safe on old paint which has been flatted back with the da?

Thanks

Albert

This is the finish I've got on the galv bulkhead which I t-washed, etch primed, hi build primed, flatted then base coat and laquered it

Should be ok. Alloy is funny stuff it's the naturally formed oxidation layer that stops it from corroding, but it also stops paint from sticking hence the need for etch primer.