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I got home tonight and was going to do a little wet sanding on the OPP. Guess what, the paint shop mixed me urethane enamel instead of urethane basecoat. The thinner was right, 2:1, but I noticed the paint wasn't hard like it's suppose to be after 24 hours. After doing some digging and thinking, I was sold the wrong paint tomorrow I will return to there and see what they have to say about this. The problem is with the urethane enamel, it takes hardner. The ratio for that system is 8:4:1(1 being hardner). I'm hoping I can set the parts outside in the hot sun for a day and the enamel will harden up enough to be wet sanded. Fortunately the clear coat I'm using is compatable, as in urethane clearcoat.
I noticed the gloss on this supposed basecoat was high, I figued something was fishy right then!
Regarding the paint store, I took them the correct part number from the last time (black) and also had them mix up a like quart from a color chip matchup (Johnson Gasolene orange).
Just another day in paradise!!

Neal

I have had this happen because I used to slow of reducer for the weather. My best friend owns a body shop will take a forced air space heater and blow it in the paint room not directly on the paint. Keep it that way for about 2 hrs and it will run up around 110 degrees. Its better than the sun because you have an even heat all around. He uses a natural gas heater 300,000 BTU and I use 150,000 BTU propane from Home Depot the most common are kerosen.
Good luck Greg

Neal,
Check with the paint vendor to see if there is a "window" for recoating that paint. Often, paints have a certain period of time that they should not be recoated. It is possible for the new paint to loosen and lift the paint under it during that vulnerable period.

Even though your single stage paint was designed to use a hardener to cure, it may air dry to an acceptable cure over time, especially with a little heat. Hopefully your paint vendor should have info on that too.

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Jim "Oldgas" Potts
Your host and moderator

Thanks for the good info guys! I called the paint vendor this AM, he wants me to strip it and start over. He will give me all the material I need but I HATE to go back to square one!! I am taking the sheet metal to my old motor shop tomorrow, put them in the bake oven which used to cure varnish/resin on motor stators. It's a super high dollar/high tech oven that slowly ramps the temp up & down, I'm going to set the temp at 130F for 2 hours.
If this doesn't work I will strip the sheet metal and start over.
The way I see it, I'm smarter today than I was yesterday, that's how I learn most of my lessons.

Footnote: regarding catalized coatings I have found that polyester resin less catalyst (for example) will cure with the presence of three things;
* elevated temperature and/or
* the presence of air and/or
* time
The same property I have seen in epoxies.

I'll make it work one way or the other!
Again THANKS for the help!

Neal

Neal, Hope you get it figured out! I too am smarter today than yesterday. I learn something new each day but dang if I don't forget two or three things every day that I used to know. LOL Good Luck Larry