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[MW:3327] Re: Painting

Saravanan, 

The painting defects pinholes and fish eyes were application failure,mainly fish eyes persist wen the coating surface have dirt,oil,silicone or any incompatible coating and pinholes persist wen spray gun too close with air bubbles forced into the coat,pressure difference in spray pot with air pressure ,or moisture or trapped solvents in spray.

Insists your painting operator for an careful operation.Only remedy is sand smooth the surface and recoat.

Any related queries drop me a mail.
 

Thanks & Regards

 

kevin mathew varghese
Senior QA/QC Engineer(Mech),FCE
kmvkerala@gmail.co.in 







From: Saravanan Mohan <sardev@gmail.com>
To: materials-welding@googlegroups.com
Sent: Saturday, 26 September, 2009 2:16:29 PM
Subject: [MW:3324] Painting

Dear Guys!!!!!!!
 
The project which I am involved following the paint systems as per client spec follows:-
 
Inorganic Zinc(75-100 micron) as a primer
High Build Epoxy(100-150 micron) as a Intermediate
High Solid Aliphatic Polyurethane(40-100 micron) as a finish
 
Total Dft between (215-350 micron)
 
After the complete curing of the finish coat visually I observed tiny pinholes like appearance or fish eye only inspector eye can find them.
 
Please give me the suggestion where the problem from? this appear in almost all the painted works which applied many different days, different paint batch followed by airlesspray method.
 
 
 
 




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