Originally Posted by Lizer
Would you wet sand body filler? My answer to that question is 'No,' which is why I elected not too. Apparently it's the same answer as Barry's. My fear is the poly primer absorbing too much water and not getting out. I think deadbodyman has actually discussed situations where it lifted when wet sanded. This clearly needs googled. I'd consider spraying 2k over it, blocking and wet sanding that but a concern of Barry's was having too many different substrates on there.
How long is long enough to breathe? After sanding these I'll be sealing in good time and I think it would be devastating to have that moisture trapped in there.
Agree with "no" on wet sanding poly primer and all the reasons you have given. The poly primer I am using now is super porous, would not even consider wet sanding this stuff as it would probably soften it up a bit. And this particular poly must be topcoated with an epoxy or 2K, hence the name its called "base primer".