All,

I’ve got a van that I’m converting to a camper and long story short I decided to Raptor Line the exterior. That project came out really nice but the mismatched interior of the doors was driving me crazy so I decided to paint them as well.

I scuffed them the same way I did the exterior, used a Upol #8 acid etch primer on any bare/damaged areas, wiped with Prep-All, and then applied Upol #4 Adhesion Promoter. The paint I used was Sherwin Williams AIC acrylic enamel and followed the paint shops 8:2:1 ratio (Paint:Reducer:Hardener). I applied 2 coats and waited 1 hour between them. The whole job went really smooth and while the finish is no where near perfect, it looked good enough for a camping/off road vehicle.

My problem is that the paint is super delicate. I started to put all the seals back on this morning (24 hours post spraying) and stopped rather quickly because I nicked/scratched the paint several times in the process. Just to make sure I wasn’t just going crazy, I lightly (like very lightly) scratched at the paint with a finger nail and the paint came right off.

I dug around the internet and couldn’t find anything, but fortunately I stumbled across this forum. I also did a search here, and while there were several topics that were really close, I didn’t see anything that really helped.

My question(s) for all of you experts is, is this normal? Does it take a long time for the paint to harden up? Will it become more durable? If not, is there a way to fix it without having to sand and redo everything?

Obviously, I’m really frustrated as the time and money involved seems wasted and I could have just just gone with a rattle can job and it would have been more durable.

Any info, guidance, or help would be greatly appreciated.

Let it sit in as much sun as you can get on it for a week and then check it. I'm betting you will be fine. Ultimate hardness on almost any modern paint job is not reached for 90 days or so. Acrylic enamel wouldn't have been my choice for paint but it is what it is.....

Right on. It’s sitting in the drive, doors open, baking in 100+ AZ summer sun. I’ll leave it parked where its at and hope for the best.

Out of curiosity, what would you have used and do you know why its so fragile at the moment?

I would have went SSU (single stage urethane). I haven't played with those old enamels in over 30 years now. ALL coatings take time to harden. Something a lot of us do is keep an eye on our "puck" which is just the left over paint from a mixing cup. That puck can be soft for quite some time and then you gradually see it hardening. If I had a puck that was not appearing to harden over time, well, then it is time to panic as the mix was probably off.....

I'm pretty sure the shop told you the wrong mix ratio.
It should be 4:1:1, which at 8:2:1 means you added only
half the necessary hardener.

Good advice about leaving it in the sun though. It should
cure fine, just take a little longer. I've painted my share of
acrylic enamel in the past, and remember the stuff would
gas off and smell for literally weeks afterward, as it cured.

I came to love that smell...

Whenever I hear Prep-all it makes me cringe. Had a very bad experience with it causing my paint not to adhere properly.

I only use paint grade Wax and Grease Remover for final wiping now.

Man… I wish I would have know that about the Prep-all and the ratios. I guess its one of those things. When you dont know about something you tend to lean on the local expertise… seems like I might have been misled.

Thank you guys for the info though, I really appreciate it.

I agree with 68 Coronet. Not a huge fan of Prep-all. If you don't follow the wet wipe-dry wipe procedure, you can have adhesion problems. Another is: what grit sandpaper did you use to sand it? I find AE like coarser sanding before paint than base/clear. I usually do 400 grit, sometimes leave it at 320. I've done some pretty nice paint jobs with Centari (Dupont's AE), and find it's very durable paint.

Probably another rookie mistake, but I didn’t sand the surface first. I scuffed it with green scuff pads just like I did the exterior when I prepped for the Raptor Liner. In hindsight, and from what I’ve learned here on this forum, that appears to have been a bad decision.

It’s better than it was the day after, but its its still really delicate. Right now, I’m thinking I’m screwed and I’m going to have to redo everything. I’m still going to leave it for a week and see if it gets better.

One thing I was wondering though, would a clear coat or three help?

Sixtop wrote:One thing I was wondering though, would a clear coat or three help?

No. The paint, even though under-hardened, will cure in time. By overcoating it you've already made it more difficult for that to happen. Adding clear will only slow the process, maybe stop it and risk solvent pop.

Leave it out in the sun for a couple of weeks.