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Sanding epoxy primer

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JPSmit

JPSmit

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So, I've got Ms Triss in the garage and have mostly cleaned up what I can clean up from my previous bad media blasting experience - told on the Sprodget boards actually. Anyway, here is my question - apparantly epoxy primer needs to be sanded before painting if time elapses between priming and painting - like a month +

What grade of Sandpaper should I use? I figure I might as well sand some while I'm waiting rather than pay the body guy to.

thoughts?
 
My advice JP, is if you are not experienced with proper sanding techniques, you can do more harm than good. Leave it to the painter at the body shop.--Fwiw---Keoke
 
Depending on who your painter or body guy is, you may or may not save any money. Most will probably redo your work anyway. I first started using PPG epoxy and liked it enough to not try others. So I can only speak for that one. If I remember right, they recommend sanding if the primer is over 72 hours old. I have had good luck with 400 grit but if you tend to be heavy handed you might try 600 first. This is all hand work, no machines. The PPG at least and probably most epoxies will develop a sort of eggshell surface with an almost oily look and feel. You just need to knock that down slightly. Just scuff the surface to give the paint something to bite into. Also, PPG recommends to shoot another coat of thinned epoxy sealer after sanding and before top coating.
 
I used Valspar's epoxy primer (I suspect they're all very similar), the final sanding before topcoat I used a block, #600 wet-or-dry and wet-sanded "flat". Rinse, dry, tack-rag and shoot top coat... Worked amazingly well.
 
I’ve seen way too many paintjobs lately with visible sanding scratch below the color coat. I'd make the final step on the primer at least #600.

I’ve seen base coat instruction sheets that even recommend #800 for the previous stage to get the best finish.


PC.
 
reading this a bit late in the game, but is the 2 part epoxy is much like the one I used it must be recoated within 3 days. If not sand with 180 grit and recoat primer before paint. More than likely you run the risk of sanding through so I would leave it until it is truely a day or so away from being painted. (To resist chance of flashing.)
 
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