Rustoleum aerosol clear coat failure

[Orca]

Hi, Asking about a 2x Clear coat failure using Rustoleum products. I prepped the metal and had a good coat of primer on the parts. According to instructions I used Rustoleum High Performance Enamel aerosol to put color on the job. Several light coats with 20 minutes between coats. Came out great . Let the job sit for 2 days to again be sure paint was dry. I then used a light coat of Rustoleum 2x Clear coat to protect the job. As I applied the clear coat the paint crazed up. I stopped and let everything dry. I tried to sand off all the paint to a smooth finish. No go. So I wire brushed the piece and re primered it again. Here is the rub, I have done the same thing with other parts and they came out great. What could be causing the crazing? Thanks

 

[BlindViper]

crazing like the paint is crinkling?

 

[CMB41]

Humidity? 2 days of drying may not have been adequate in high humidity. Did you wipe the enamel down with mineral spirits before applying clear?

 

[mreisner]

You either have to apply the clear coat within the recoat window like your other coats or wait for it to totally cure which I believe is 2 days, but that is highly dependent on temperature and humidity. Since it is an enamel and it cures not dries like lacquers. The solvent from the clear coat soaked into the base coat which was not cured but merely dry on top and that caused the crazing. Generally you need a minimum of 48 hours at 70° and less than 50% humidity. To be safe 3 days at least, or better yet just put the clear over the top after you finished your color coats and that should insure no crazing and also good adhesion.

 

[dnschmidt]

This is a common problem with automotive basecoats as well. You typically want to get the 2K clear on them within an hour or crazing can occur unless you've added activator to the basecoat which is the best option but is seldom used as activated basecoat cannot be stored once it is activated. Considered the price of basecoat throwing 8 oz. of this out is very painful. What you are experiencing is a partially cured color (meaning you waited too long) being attacked by the solvents in the clearcoat.

 

[PWC Repair]

Sounds like the 2x clear is LAQUER.........which atteacked the enamel. I've found out you really need to test any spray cans on a test surface first because they DON'T tell you what the base product IS!!!

 

[Bert_]

Not real helpful but I used the Rust-Oleum clear on the trunk lid of my car. I lightly sanded the failing original clear coat and sprayed this stuff on. Put on several coats in no particular amount of time.

I am pleasantly surprised it is holding up fine so far. Very happy for the price. Time will tell if it holds up long term

 

[Orca]

O.K. Thanks for the replies. Odd that some sections crazed while other areas did not. Thought 2 days in the sunlight would have cured the base coat.. Will redo with advice given here. Appreciate the help.