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Spray Defect:Fisheyes/Cratering/Cissing

2000

Hi, my names is Jonathan Twynham and I live in the UK. My father and I are trying to restore an old Jaguar, but every time we try to paint it, it always has fish eyes/craters/cissing in it and no matter what we do it will not go away.

We have tried swapping air compressors, paint, spray guns, airlines, we have even tried painting in a different building in our yard. The building we were using is fully lined, it has an overhead ventilation system, sealed and painted walls, painted floor. We have even tried using a special paint that is supposed to seal in any defects so that you can paint over the top.

We were told that this defect is caused by silicone - we have used anti-silicone wipes, anti-silicone liquid in the paint, but it does not work.

The paint that we are using is 2K

Jonathan.

P.S The paint defects looks like this: (side view)

_______ _______ paint surface



 
 
 
\ / 



 
 
 
--0--     particle below paint surface

Jonathan Twynham
- Mkt Harborough, Leicestershire, ENGLAND, UK

Check the following for contamination: Air supply (needs good filtration, no oil, no water, extremely clean), environment (are you around any silica sand producers, is there any caustic or acid around, etc...), based on what you have stated above, I would look at the base metal itself, is the defect already there, so what you are painting is highlighting it? Get a cheap 30 power microscope from a hobby shop and check it out.

Rick Jacobson
- Sedalia, Missouri, USA
2001

Hi, my names is VISHWAS SHEWALE and I live in the India. I am working in one of the reputed spray painting companies. We do spray painting job on ABS and PLASTIC parts. We are facing a problem of fish eyes/craters/cissing on base coat parts. fish eyes/craters/cissing mostly occurs on ABS parts.Some times it appear after clear coat application also.We would happy if you could guide us.

Vishwas Shewale
production supervisor - Nashik, Maharashtra, India
October 4, 2011

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Hi, Vishwas.

Can you please post your question in terms of the suggestions already provided, so that we don't just go in circles?  :-)

What can you tell us about your air supply, the local application environment, and what you see with a 30X scope please? Thanks!

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October 4, 2011