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Finishing problems when using water base CARC paint

2007

Hello,
We are a company that specializes in the machining of aluminium parts. Our finishing department does the surface treatments and painting of the parts. We currently are encountering a problem when applying waterbase CARC paint to our parts. The paint bubbles in the drying process.

We need to paint pieces that are composed of multiple fins of 1/8'' in width and ¬ to — in depth, with CARC (Chemical Agent Resistant Coating) Military water based paint. The pieces are Aluminium 6061-T6 and where treated with class 3 chemical film before being painted. Up to now, we have always used standard Green CARC paint and have obtained very good results. We will need to continue our production with the water based paint. Since the beginning of August, we have been experimenting with this paint on our products. We need to obtain a uniform smooth finish on all surfaces.

With the water based paint, we obtain good results with the surfaces are flat and even. But, we are getting bubble formation on our fins after the drying process. We have tried different techniques, but we have not gotten very positive results (change numbers of coats, paint mixture, application sequence and drying time).

It is extremely important for us to resolve this problem and help would be greatly appreciated.

Thank you!

Sindy Blais
Paint shop - Quebec, Canada

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The water dispersable CARC will blister or bubble when it is applied too heavily. Contact your paint mfgr. for wet film thickness requirements.

Bill

William Morgan
- Saratoga Springs, New York, USA
2007