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Ted Mooney, P.E. RET
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Paint chip-off
2004
Greetings!
I would like to ask, what are the probable causes of paint chip-off after phosphating has already been done to the metal?
Thanks!
automobile restoration - Manila, NCR, Philippines
Hi Richard,
Poor cleaning, poor phosphating, poor rinsing, poor paint application and poor paint curing are possible causes for your problem.
- Naperville, Illinois
2004
The most common cause I have seen over the years is poor rinsing prior to phosphating. The phosphate forms crystals on the surface due to a pH change. This is normally the result of the acid reacting with the metal. A layer of soap gives the required pH change to form the crystals without any real adhesion to the metal.
Ronald ZeemanCoil Coating - Brampton, ON, Canada
2004
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