Preventing chipping paint

Desertguy

New Member
My wife's car was repainted by a small shop about 5 years ago and I don't want the same problems she has on my Cherokees paint job I'm working on. Her paint has tons of rock chips on the front. She's probably only driven 15k miles in that time. The painter I think said he used Sherwin Williams primer, and I'm not sure about brand of BC/CC on top. The chips seem to be mostly taking the BC/CC off and I can see the buff color primer still there. What could be some reasons that the paint isn't adhered well to the primer? Not scuffing or cleaning enough before paint? No seal coat?

I'm in the process of painting an old Cherokee. Have sprayed SPI Epoxy, and my SPI 2k primer comes today and I'll do a seal coat once blocked good. I want to do this right.
My Jeep will do a lot of off-road, so I don't want the same issues. Any ideas?
 

Jorge M.

Member
Use the epoxy mixed 1:1 with reducer as a sealer before your basecoat application, activate the basecoat with the SPI clear activator even at 3% will help with durability.

Give plenty of flash time between color coats and specially between base and clear. This should make your paint job stronger than any collision insurance job out there.
 

Desertguy

New Member
Great. I've got an extra gallon of reducer to thin the epoxy. That's good to know about the activator in the base coat. Sounds like a plan. Thanks
 

crashtech

Combo Man
Not using activator on the base makes the system way less chip resistant. Using cheap primer with lots of fillers seems to make things chip prone as well. There was a brand of primer made by a major that was notorious for being weak like that, guys loved it because it dried fast and sanded easy, but it actually sucked at everything else.
 

Jorge M.

Member
Not using activator on the base makes the system way less chip resistant. Using cheap primer with lots of fillers seems to make things chip prone as well. There was a brand of primer made by a major that was notorious for being weak like that, guys loved it because it dried fast and sanded easy, but it actually sucked at everything else.
It’s commendable that you don’t want to name names, my curiosity is picked though
 

Desertguy

New Member
So if I do an unreduced coat, then a flow coat of epoxy, do I sand flat next day, or will it be pretty flat that I can just clean and spray base the net day? This will be over my epoxy, filler, epoxy, 2k primer.

I'll definitely be activating my base. Glad I checked with you guys because I didn't realize exactly why I would do that.
 

Jim C

Oldtimer
you can go 2 ways here. you can reprime with epoxy and sand flat before you apply base but you need to get your base on within 48 hrs. imo, this is just a reprime. you can also reduce your epoxy down and shoot as a sealer. mix 1:1:1 or reduce 25%, spray just 1 coat over your 2k primer, wait 15-30 min or until it flashes dull then go right to your base. you will get better adhesion with the seal method but it also wont cover either or fill in any sanding scratches so if your are shooting a poor covering metallic and you blocked your 2k with 320/400 then you might want to go the first route.
 

texasking

Active Member
It was NCT or NCP a non iso primer, forgot the exact name.
That primer(NCP 250, I believe) cost PPG a complete repaint on a Mercedes that I did. Painted it for my father in law because of a few dings and chips. Spot primed everywhere and left it out 2 days in the sun. After painting it sat 2 days outside and every single spot I primed ringed out because of shrinkage. I raised enough hell with the rep they wrote me a check to respray it plus material. Never used it again. Their experiments with non-iso primer and clear(dc 1100) was a big failure. It never fully cured.
 
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