Basecoat Adhesion Issues (BITING?)

What causes this???

@Lstyke This is commonly called BITING. Usually something underneath or an unclean surface. Uncured putty (or even lacquer putty?) I hope you didn’t use any of that. Could also be the paint or feathered paint/primer below it. I don’t think it was properly sealed underneath. Did you paint over a 2k sealed primer?

Anyway the FIX: Sand it out 400-600 grit - Prime the area in light coats 3-4. Sand flat with 400-600 and rebasecoat and clear. Good luck!

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@TonyB I did use a 2k primer that I feathered out. However it did not occur on the edges of the primer as I rebased the entire hood. Areas not needing repair I wet sanded with 400. Could this also happen if I laid my second basecoat too quickly??

BTW I learned everything from you and really appreciate all you have thought me. Thanks

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It is a possibility because your first coat wasn’t completely dry. Spraying too wet can cause this, but is not common if the undersurface is prepped properly. Hope the next layers spray on good. Remember, I would mist and spray the next coats especially over that area lightly until you cover. Use a lot of air and dust the basecoat. I talk about this and show you in VIP. Here’s a good video: https://www.youtube.com/watch?v=e0Ompce3wVg

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The following are photos of car following sanding down of biting issues, dusting 3-4 light coats over areas where this occurred, a couple heavier base coats, and then 2 coats of clear. I plan to color sand and buff and upload pictures to see if anyone can tell a difference.

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@Lstyke looking forward to the finish pics :sunglasses:

@Lstyke - Not too shabby my man, great job!

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Is what you call Biting the same as alligator skin? I always heard to referred to as alligator skin, just want to make sure we are talking about the same thing

Look at the first picture in the thread. Whatever you call it that’s what it looks like lol

The only other thing that I know you may be referring to is orange peel where the paint has a texture. When you look at reflection of clear coat it is not smooth

Tony’s first response was correct. It is a chemical reaction caused by something not agreeing with the paint that you laid on in that area. I live by sealer for this reason. It cost more in price but skipping it causes more time, aggrevation and paint/ other materials.

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Any 2k primer will do as well. You just need something that will seal the paint to give it a good foundation to paint over. Welcome to the group my man!

I found out the hard way after redoing it like a million times. What caused it was the reducer used in the clearcoat, also the clearcoat itself is causing it at a lesser degree. test this by using an old hood, sand it smooth and spray on basecoat, allow to fully dry 30 mins or 1 hour. next clean your gun and put in ONLY the reducer for the clearcoat, just the reuder, nothing else, you may notice that cracking reaction in seconds. if you were not using any reducer for clearcoat, make a tiny batch of clearcoat and get a stick and drip some on the dried basecoat, try to smear the clearcoat on that dried basecoat, does it dissolve it? that’s your problem, bad solvents in the clear. for me I simply test several reducers for the clear and settled on ppg omni 186 medium reducer, less reaction to basecoat. I was using proline reducer and pro32 clear, both have horrific reaction to ppg base. solution is either substitute reducer with a stable tested one or stop using that horrific clear, cheap clear and reducer have cause a nightmare for me. next I’m trying to figure out why my omni base has so much mottling for metallic basecoat. not sure if it’s my gun or what