Reply to: Re: Wet Sanding
Mike Gendimenico admonishes us to prevent sand scratches by wet-sanding our
primer. I used to do that. I don't anymore. Dry-sanding is a pain in the
butt; the sandpaper lasts about two swipes; then you have to change it. But
it's better than having a job ruined because of water in the primer. See,
Lacquer primer/surfacer is quite porous. In fact, it soaks up water like a
sponge. You might think it's dry, and spray your color coat. In fact, it
isn't dry, and it lifts up your color coat in little "zits". Not only that,
but it gets down to your metal and rusts it.
To wet-sand successfully, you should:
* Preceed the primer/surfacer with a sealer, so that the water can't get
to your metal.
* Let the wet-sanded primer dry FOR A LONG TIME. Maybe two weeks would
be enough; I don't know.
On the other hand, dry-sanded primer can be color-coated as soon as you're
through sanding it, and you will never get water trapped down there in it. A
body man showed me a trick. You get a piece of coat-hanger wire, and bend it
double, making a tool that you can whack the sanding block with, right on the
paper. When you whack the paper with your sproingy coat-hanger tool, the
sandpaper clears off as if by magic.
Another trick is to use the sandpaper 'till it gets clogged, then wash it
in the sink. Hang it up to dry. You can always tell when I'm sanding primer,
by the clotheslines :-).
- Jerry
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