Fisheye problems

[kylelord]

I just sprayed a test panel with Omni paint, and had many many fisheyes appear in the paint. From what I understood, they come from something the paint can't bond to underneath. However, I went afterwards and took a rattle can and sprayed over, but that didn't fisheye. Another thing I'm wondering about is the hardener. It's a few months old, but has been closed the whole time after it's first use. Could that cause a fisheye? The last thing I could think of is my application. I put it on kind of heavy, without letting it tack in between. Should I have done a tack coat first, then put a heavier second coat on?
Sorry for all of the variables, and thanks for any help.
Kyle

 

[blaino]

Kyle,

First off ...Are you spraying Single stage or spraying Primer or Clear because PPG Omni system does not use harder in the base (At least, not the MBC).
Fish eyes from what I have learned, are do to Oil contamination if not from your air compressor then from your skin.

Here a link for ya....
http://autobodydepot.net/sol12.html

 

[kylelord]

Thanks for the link. I was spraying with single stage omini.
Thanks,
Kyle

 

[rex]

Fisheyes are from contaminants like oil,silicone,wax,etc that was either put on the surface and sanded in or from airborn stuff done upwind and it settles on it.If they were there from the first pass of the gun the surface wasn't clean.If they happened later into the spraying either contamination was sucked in the booth or pumped through the airline,or it's solvent pop from hosing it on.Some paints will look like they have tiny fisheyes but it's really a pop that has popped.I've had PPG's singlestage do it and a few of their older clears.I'm aweful about preaching about putting it on thin but I get heavy handed at times too.

 

[kylelord]

I'm not sure if they are fisheyes or solvent pop, but they have the substrate color in a little circle with a dot of the paint color in the middle. I'll do another test panel tomorrow, and this time double check the cleanliness of the surface, and spray a tack coat on, then proceed with a heavier one. It wasn't contamination from a booth because I was spraying outside.
Thanks for the help,
Kyle

 

[rex]

Yea,sounds like fisheyes.Use a good wax and grease remover for the first wipedown and be sure to keep drying until it's dry,don't just wipe off the top and move on because if it's still wet it's still floating contaminants.Sometimes I wipe it down twice if I can see the fisheyes in the wet solvent.The quicker drying ones work great if you'll need to wipe down sealer or basecoat but you have to use alot of it the first go.Don't use lacquer thinner or anything but grease and wax remover.