Just had a paint reaction on a 2021 Civic hood in the middle of a blend

I was spraying a basecoat blend on a silver Civic in the booth when the new paint started wrinkling at the edge of the old panel. I had to stop, sand the whole mess back to bare metal, and re-prime before starting over, which added about 4 hours to the job. What's your go-to method for checking solvent compatibility on these newer waterborne systems?

3 comments

3 Comments

the_nina1mo ago

Oh man, that "wrinkling at the edge" is the worst, I always do a test spray on a scrap fender now.

nancy_smith1mo ago

Ugh that solvent pop is such a headache on these newer cars. Read a tech bulletin once that said to always do a test spray on a taped-off section of the blend area, like @the_nina said, but also to let the old paint flash off way longer than you think. Those factory clears can hold solvents forever. Had a similar thing happen on a Toyota bumper, the new coat just lifted right off. Now I hit the edge with a gray scuff pad and give it a solid thirty minutes in the booth heat before I even think about spraying.

grace_allen25d ago

Hold up, I gotta push back on this a little. In my experience, those test sprays on scrap panels don't tell you squat about how the actual car will react. Your scrap piece isn't cured the same way or baked in the same factory conditions. I've had perfect results on a test fender and then total wrinkling on the real job. Honestly, I think most of those "wrinkle at the blend edge" problems come from not letting the factory clear flash off long enough before you shoot. I'd rather just scuff the whole blend area back a little further and give it a good 45-60 minutes in booth heat. Your mileage may vary, but I stopped test spraying a while back and just focus on prep time.