What does wet-sanding do?

[10 count]

What does wet-sanding do that regular sanding doesn't?

Thanks.

[MONeill854]

The water used during wet-sanding acts as a lubricant and 'smooths' out the
abrasive effect of the sandpaper being used. This results in a smoother finish
and also helps to eliminate the 'deep' scratches that can occur in a painted
surface being sanded 'dry'. Be sure to use wet/dry sandpaper as regular
sandpaper will just disentigrate when wet. Before wet sanding, make sure that
the underlying base material that was painted won't be negatively affected by
getting wet (i.e cardboard body tubes are best not wet sanded!). Also, enamel
and epoxy based paints usually don't sand as well (dry OR wet) as do lacquer
based paintes. Hopes this helps.

Mike O'Neill

[Bob Kaplow]

In article <7q49vtg6o63q4dhm6...@4ax.com>, 10 count <spa...@testor.org> writes:
> What does wet-sanding do that regular sanding doesn't?

The water acts as a lubricant, carrying away the sanding dust. The end
result is s smoother finish and less dust in the process. Yuo do have to use
sandpaper that can handle water. Both the backing material and the adhesive
must be impervious to DHMO. The mylar and cloth backed stuff is OK, the
paper stuff is not.

Bob Kaplow NAR # 18L TRA # "Ctrl-Alt-Del"

Kaplow Klips & Baffle: http://www.nira.chicago.il.us/Leading_Edge/MayJun00.pdf
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[Bob Kaplow]

It's been a long time, but my experience with epoxy paints was that thye
sand as well as laquers.

Bob Kaplow NAR # 18L TRA # "Ctrl-Alt-Del"

Kaplow Klips & Baffle: http://www.nira.chicago.il.us/Leading_Edge/MayJun00.pdf
NIRA: http://www.nira.chicago.il.us NAR: http://www.nar.org

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[Jon Rose]

It also has the added benefit of not loading up the sandpaper like dry
sanding does. The material washes out of the sandpaper pretty easily making
it last a long time. Before switching to wet sanding I used went through a
few packs of sandpaper for each rocket. Now I go through a few pieces
(usually 1 in each grit).

Jon

"Bob Kaplow" <kapl...@eisner.encompasserve.org.mars> wrote in message
news:j+PTRj...@eisner.encompasserve.org...

[Stefan E. Jones]

Another benefit of wet-sanding:

Sanding generates heat, which can actually muss up plastic surfaces.

A bit of water helps things cool down.

I sand almost every plastic rocket part I use. First I use the edge of
an Xacto to scrape away the flash and mold lines.

I might follow up with ordinary dry sandpaper, to grind down the
remaining flash, but I try not to actually scratch the surface.

Then I wet sand (actually _underwater sand_, in a basin of clean
dish-water) using black (320 grit) mylar-backed sanding material. With a
little work, you can eliminate all traces of the mold lines and kill the
"phony gloss" of a plastic surface. Sanded and polished plastic isn't
glossy, but it is smooth.

[The Silent Observer]

MONeill854 wrote:
>
> Before wet sanding, make sure that
> the underlying base material that was painted won't be negatively affected by
> getting wet (i.e cardboard body tubes are best not wet sanded!).

Actually, I routinely wet sand balsa fins and paper tube after several
coats of primer to seal the surface. This isn't a problem, providing
you're careful not to sand through the primer and expose the base
material. One very good way to avoid sanding through the primer: apply
one color for the first one or two primer coats, and then use a
contrasting color for following coats -- I use black for the first, and
gray for following. When I see black, it's time to stop sanding that
area.

After thoroughly drying the water from wet sanding, when applying more
primer, I again apply a witness coat of black before more gray. Works
very well; I haven't sanded through on the paper body tube since the
first time I wet sanded.

--
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Donald Qualls, aka The Silent Observer NAR # 70141-SR Insured
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Opinions expressed are my own -- take them for what they're worth
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