Use a 3M fiber pad....NOT steel wool or sandpaper
Thanks for the reply. All the things you mention are what I was concerned
about. I think I may just wipe it down with mineral spirits & paint it w/o
the abrasion. The primer is flat, and no doubt quite thin. I'm imagining
that sanding through to the bare metal and subsequent rust is more of a
threat to the final finish than the need for adding more "tooth" to the
already flat primer.

Dan


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