If I can I will post some pictures but here is the problem. 42 Ford paint prep, sanded fenders to metal and sprayed epoxy primer. 1 fender sat 3 weeks other fender 2 days. I didn't use 2K primer on top of the epoxy primer, but used a laquer primer because I was told that worked just fine. Fender that sat 3 weeks, it got scuffed good, looks fine. Fender that was 2 days old has more crackle in the finish than a lot of repro antique furniture that I've seen. The crackle also went down into the epoxy primer, it wasn't just in the primer on top. I also saw that the epoxy primer was softened and I could scratch it with a finger nail, it was kind of gummy feeling. Tonight I sanded down to the expoxy primer and resprayed the laquer primer, let that set for 30 minutes and sanded down to the epoxy primer again. Everthing is smooth now, but like I said the epoxy primer is scratchable with just a finger nail at the moment Question is this, what do I do now??
If you live anywhere in this state, KY, you sprayed the first fender in a different weather pattern than we have had for the last 8 days. Several days of high humidity will cause problems. The epoxy may have never had a chance to dry. Give it a day or two to dry with the lower humidity levels and then shoot a coat of lacquer on it and watch the reaction. If it takes go for it. Had some blushing going on myself, so I put the gun down until this afternoon. Good luck.
Strip it ( all ) off. I would say the primer /activator mixture was wrong. 80da, to bare metal. Then 180da, blow it off .. wipe with pre cleaner , with clean paper towels. Listen now ! 1 light coat wait 5 min. = 1 med coat wait 10 min. = 1 heavy coat wait 15 min. = 1 last heavy coat.
Oh yea.. DO NOT. Listen to other bs. (Like put acrylic lacquer primer over epoxy) .... that is extremely. Bad info...
Did you read the tech sheet for the epoxy? Some take as long as 7 days to fully cure. The lacquer thinner in the primer most likely penetrated the uncured epoxy. Also, mixing product lines is never a good idea. I know some people "do it all the time" and it works, but how many times do you want to do this? The tech sheet spells out the acceptable under/overcoats for any product...
Do not put lacquer over the epoxy...its called the oreo cookie syndrome. The bottom it still moist and the top is hard..two different curing times. If it were mine..sand it down and redo using the epoxy or a DTM (direct to metal.) Which uses a etch primer and surfacer all in one, for good adhesion....good luck
Good info here. Mixing product lines is bad news. I agree also with stripping it completely. If you're having issues this early they will only come up again to haunt you later. Whether it be when you apply your base/clear or single stage or 5 years from now when you have cracks all over from checking or other paint failure issues. On all my bare applications I apply 1 to 2 medium coats of etch (direct to metal) primer (letting it flash off between coats) let it flash an additional amount after last coat recommended by the manufacturer and then apply my 3 coats of primer surfacer for blocking. Let that sit for 2 days before sanding if the temp is at least 70. Let sit longer if its cooler out. I'm a big fan of PPG stuff. Great results Posted using the Full Custom H.A.M.B. App!
Simple as staying away from lacquer. If you spray epoxy, go over it with a 2k sealer, then your top coats.
If you are looking for a great long lasting paint job, start over. Laying anything over it when it's not cured will just end up in a bad way. Take time and do it right. Double check your measurements. Use products from one line. Wait for dry air days. Just slow down and cover your bases and you will have an outstanding finish. Posted using the Full Custom H.A.M.B. App!
Pretty simple, you have the evidence of what went wrong. The epoxy that was 3 weeks old looks fine because it fully cured, the rest the lacquer thinner ate into the still uncured epoxy. Lay a rag wet with thinner on cured and fresh epoxy and you'll see what happened right away. I know lacquer products are not recommended anymore but we used them for years incuding over DP epoxy primer, it can still be done. Just got to have lot's of patience with them, any non lacquer product must cure at least a week before you go over it. One problem with all lacquer products is there is a fine line between shooting it too wet where it attacks the underlayment and too dry which leads to poor adhesion. That fender that looks good now will be fine to continue on with, the other, sorry but that softend epoxy gotta come back off.
I learned the hard way (like you are) not to use laq. primer over/under any 2K paints.... I'd strip it down to the epoxy (or in the case of the wrinkled one to bare metal), then either go over it with a 2K primer/surfacer and then a 2k sealer, then paint..... or epoxy, then sealer, then paint.... to many chemical reactions to deal with..... it is not so important to keep all the same "brand" paint as it is to keep the same "system".. it all needs to be compatible.. You have not said what topcoat you will be using (single stage, Bc/CC)? Tom
Thanks a lot for all the advice. I kinda figured it was a start over kind thing. Oh well, at least I didn't spray the body and doors, that would have been ugly bad. It will be painted with a single stage paint, a midnight blue on the hood, body/doors and trunk lid. Interior is also going to be grey. The four fenders and front end will be a charcoal grey and possibly ghost flames coming from the front fender stopping just before the back fenders.
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