Re: Did I Ruin It?


ed_mines
 

Professor Golden is correct.

 

I was senior chemist at HumiSeal (supplier of sprayable, solvent borne coatings) for 12 years.

 

The whitening is caused by moisture condensing and is called gun blush. As solvent evaporates it draws heat away from everything in the vicinity of the coating. When the coating temperature goes below the dew point moisture condenses on it, sometimes causing spots and sometimes whitening the entire coating.

 

Humid days have higher dew points.

 

Occasionally the whitening can be eliminated by baking in an oven, but plastic may deform before the white goes away.

 

Ed Mines

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