Wet Etch Primer

[MK1_Oz]

Took the shell to have it's cage put in today and blow me down if it didnt rain all the way into the hills

I put a car cover on then a tarp and some of the car still got wet (spray off the road I suppose).

Should I be worried about rust forming under the etch???????? Should I strip the areas that got wet?

[ozstang65]

Etch is a pretty good seal, unlike undecoat primer/filler which is as good as a sponge.

[Danny M]

I was advised by the guys at PPG that Etch and I used their 2 pack Etch primer that it's porous and shouldn't get wet
Also use the best etch you can was another thing they stressed

Danny

[MK1_Oz]

Cheers Danny. Pretty much as I thought. I am using Protec Etch which I am led to believe is a very good one.

Sounds like I need to do some stripping just to be safe.

I will contact Protec today to get their opinion too....

[gen mk 1rs2000]

i use pro tec etch all the time , never had a problem , it seems to
be prettywell waterproof
if you are worried wipe down an area with ACETONE
& see whats underneath , i think you will find its ok

[MK1_Oz]

Thanks again fellas. I just spoke to Protec and on either the Vinyl Etch Primer (426) or the Etch Pro Black he said just to scuff the surface back with a scotch brite pad then reprime as a holding primer.

This is good news as a 20 minute rub over is much better than hours of paint removal!!!!

[jpayne]

While many of these paint systems are hygroscopic there must be some tolerance for moisture as many repairs are wet sanded prior to color to get a smooth base finish. wet sanding involves water.
Or am i missing something in their preparation which shouldnt have a wet sanding stage, you think you may have hours of paint removal Oz, Id have years! ahhh

JP

[Danny M]

Yeah but it's usually after it's had spray putty primer that gives an almost paint like finish when blocked back where etch is quite porous and doesn't have any real "fill" properties

Danny

[ozstang65]

2 pack high build primer is usually sanded dry, well, by me anyway. Undercoats are not so much hygroscopic, but porous. If you wet sand and dry it out then there's probably no harm, but to leave it un-topcoated for a long time isn't good. 2 pack high build seems to sand better dry anyway.

I've used Wattyl super etch as a long term cover after fixing panels and before final finishing, no problems. Maybe a light sand and a fresh coat of etch before going for the undercoat. Having said that, it's not as though they are left out in the weather either. I'm also surprised how well 2 pack topcoat works directly onto etch. I did this with the door handles and bullbar on the F100, no flaking to date.

[gen mk 1rs2000]

ozstang , i have used watyl etch on aircraft for over 20 yrs
more recently , pro tech etch & found very similar results ,very good !
next best thing is zinc chromate etch primer (yellow in color)
used on all
good quality marine or aircraft grade alloys ,


my method now is , protec black etch primer
then
a light coat of 2 pac black
then
a coat of clear 2 pac gloss
sometimes i just 2 pak clear gloss
straight over the black etch
just make sure the part you are painting
is nice & clean & dry & warm
before painting