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  for Metal Finishing since 1989
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Two coat process cracking

Could someone please advise the cause of a two stage process cracking underneath the clear coat? The product is metal handrail. The clear coat feels smooth and unbroken however you can see cracks in the color coat beneath.

Thanks,

Kent Houston
- Ft. Collins, Colorado
2001

Dear Kent,

The cracking on the handrail is caused by the clear topcoat's solvent system attacking the bottom color coat. It sounds like the color coat is a synthetic air-dry, which would produce a very high gloss color. If incompatible solvent systems are being used, then you will get that "lifting" and cracking. The handrails will probably need to be stripped and repainted for repair.

Good luck.

Jake Koch
G. J. Nikolas &Co.,Inc.

Bellwood, Illinois

2001