>>Varnish never totally dries, which makes it very good for covering
>>something that might be exposed to water (like a sailboat!). I
>>wouldn't think it would cause any warpage on the backside of a dash, esp.
>>a plywood one
Actually, it's a GOOD idea to always finish BOTH sides of any piece of
wood. It turns out that only finishing one side will CAUSE warping.
The back (unfinished) side will dry out (or moist in??) faster than
the front (finished) side, and since wood changes its size with
varying moisture content, we get warpage because the back changes
faster than the front.
Having said all that, allow me to point out that plywood is extremely
stable, even in the face of such differential humidity, so do what you want.
I would say finish it all around to prevent rot, especially if you leave the
top down and the car outside at night.
--berry
(Finally got my TR6 engine mounts changed and the radiator recored, and
am happily commuting. Now if I can only find a headlight dip switch (floor
mount) and figure out what's loose in the rear end...)
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