Hey guys, was wondering if I could get some input on why you think this may be happening. Could be normal for all I know?? Anyway, this is Evercoat 4:1 feather fill poly primer. Sprays out nice and fills pretty decent, but seems to clump up on the paper when you first get after it. Once you have the outer shell sanded off out doesn't seem to do it anymore. I'm posting some pics, but they may not show very well.

Should add that it had dried for about 24 hours before I started sanding it, and it says it can be ready to sand from 1-3 hours depending on build. This was 3 medium wet coats.

Should have said this was with 120 grit paper.

yea the 4:1 does that. is that 3m red paper? try 3m purple paper.

Yeah its 3M red. I got at it with some 80 grit first and it didnt do it with that. I will try some purple next time.

I keep a red scotchbrite pad nearby to scrub off the primer that sticks to the sand paper, it helps sometimes and gets a little more use out of the paper. Also I DA the primer a little first to get that hard to sand film off before blocking.

I have a semi soft brissle brush to knock it off with, or a blow gun. Probably wont be using that primer again though. Doesnt seem worth it.

I absolutely always start with 80. No problems.

I'm finishing off every last sheet of all random sand paper I have and going to Eagle paper exclusively. Their MaxCut paper is the most amazing stuff for blocking I have ever seen.

www.amazon.com/Eagle-749-0080-Maxcut-SUP...per-Tack+File+Sheets

It's the resins in the filler that causes it. using the 3m dry guide coat powder before sanding helps to reduce the clogging.

Once you get through the "shell" of the primer it doesnt do it anymore.