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  for Metal Finishing since 1989
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Humidity-spray booth-waterborne paint

I wonder if anybody has some data on the effect of high or low humidity in the spray booth when applying a waterborne paint. Especially the effect on paint adherence and corrosion is of interest. Is absolute (g/mů) or relative (%) humidity determining?

Best regard,

Peter Piessens
- Bertem, Belgium

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We have converted our entire corrosion control operation to waterborne "direct to metal" coatings. However as we generally have over 80% humidity and high temps. (over 85 °F) would we be locking moisture into the metal, thus reducing the effectiveness of the coat? I am looking into a spray room with AC and a dehumidifier, actually a conversion of an old Binks oilfall unit. Use would be intermittent, maybe 2 times a week. Would drying the item to 40% humidity, and cooling it to 75f, shoot it and leave in the cool room overnight help? Any reply would be appreciated.

Thank you very much,

Gordon Tilley
USAF - Hnolulu, Hawaii

Try a rapid dry dehumidification system with a high air velocity.

Jim Kemmerer
- Pittston, Pennsylvania, USA