Block Sanding Repair

Craigbro63

Promoted Users
I'm currently block sanding my 2k at 320 and have a few very small break throughs to metal which are maybe 1/16 diameter at the largest. See pic areas circled in red, note not all area is metal- grey epoxy primer shows.
I will be spraying an epoxy sealer before basecoat and was wondering being these are really small areas if it is common just to continue to 600 grit as planned and the epoxy sealer will take care of these areas?
If not what is the recommended process.
Thanks!
 

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Are those lighter spots filler or sand throughs to something else? The epoxy sealer will take care of the metal spots, but filler needs full strength epoxy or 2K before sanding with 600. Looking at that, I would shoot a coat or 2 of full strength epoxy over the whole thing, then final sand.
 
The lighter color is grey epoxy primer below the black 2k. There is no exposed filler. The metal spots are typically surrounded by the grey epoxy primer in the picture where the red circles are.
My plan at this point is to sand 400, 600, then epoxy sealer as long as no other issues arise. Sound ok?
 
First question you need to ask yourself is, what level of paint job are you looking for?
If this is to be a show car, it will take a bit more work like Texasking is suggesting. If just a driver and you don't mind seeing a few flaws then continue as planned.
 
Thanks for the responses and patience!
I guess the exact question should be, will the epoxy sealer show through or fail on the metal spots?
If so, can I touch up epoxy just on these spots and continue sanding or would I need to re-coat the entire panel? Also, no exposed filler anywhere.
 
Anytime there are 2 layers of differing materials showing, there is a chance of a "ring" forming. It is caused by the epoxy and 2K, for instance, having a different porosity. The epoxy will not let solvent penetrate like the 2K will. Like '68 mentioned above, it depends on what your expectations are. Sealing and painting what you have will not cause failure, but you may, or may not, see the sand through spots in the finished product.
 
Anytime there are 2 layers of differing materials showing, there is a chance of a "ring" forming. It is caused by the epoxy and 2K, for instance, having a different porosity. The epoxy will not let solvent penetrate like the 2K will. Like '68 mentioned above, it depends on what your expectations are. Sealing and painting what you have will not cause failure, but you may, or may not, see the sand through spots in the finished product.
Understood. Would spraying full strength epoxy rather than reduced over the full car as a sealer work?
Would I spray at the current 320 grit then pick up with 400 and 600 after the epoxy?
 
Full strength or reduced 10% will fill 320 scratches easy. Shouldn't need more than a light sanding with 600 after overnight dry before base, unless there are issues. If there are, you could wait 30 minutes and apply a second coat, then sand with 400-600 the next day.
 
Full strength or reduced 10% will fill 320 scratches easy. Shouldn't need more than a light sanding with 600 after overnight dry before base, unless there are issues. If there are, you could wait 30 minutes and apply a second coat, then sand with 400-600 the next day.
Got it. I appreciate your, and everyone else's advice!
 
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