Letter 6041

Spray defect:Fisheyes/cratering/cissing 

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Hi, my names is Jonathan Twynham and I live in the UK. My fatherand I are trying to restore an old Jaguar, but every time we try topaint it, it always has fish eyes/craters/cissing in it and no matterwhat 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 ouryard. The building we were using is fully lined, it has an overheadventilation system, sealed and painted walls, painted floor. We haveeven tried using a special paint that is supposed to seal in anydefects so that you can paint over the top.

We were told that this defect is caused by silicone - we have usedanti-silicone wipes, anti-silicone liquid in the paint, but it doesnot 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 for a local hobby shop and check it out.

Rick Jacobson
- Sedalia, Missouri, USA

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