Bob and Reuben,

Your postings are the first I have ever printed from
RAS for reference.

When addressing the question of to what extent liquid
water can penetrate a gelcoat surface and whether or
not to wax, would either of you be prepared to comment
on whether reduction of gelcoat surface deterioration
by using a UV filtering polish (e.g. Wx/block + Wx/seal)
will have a significant effect on the ultimate advice?
Apart from crazing a non waxed weathered vorgelat
gelcoat also eventually goes dry and powdery and looks
and feels like it would soak up liquid water into its
surface layer more easily than a highly polished and
uv protected (by polish or covers/hangaring) gelcoat.

BTW, and in support of the opposite point of view,
I have been in the sad position of monitoring a friend's
Std Cirrus that has not been out of its metal non insulated
trailer in Scotland for 10 years. The fuselage was
rebuilt in about 1981 and painted in vorgelat. The
wings are original Scwabbellack. Both were fine in
1993 but since then, in the dark, the fuselage has
crazed dramatically and became dull and powdery so
that (before I polished it a year or so ago) you could
get your clothes white by coming into contact with
it. This expensive unintended experiment confirms
that gelcoat can definitely detriorate very badly in
the virtual absence of UV. Is this just moisture or
does vorgelat gelcoat just molecularly age no matter
what?

It would be fascinating to store gelcoat glider samples
in a typical glider trailer in the dark - some polished
and some not - and to see whether it polish does or
does not prevent moisture and temperature gelcoat deterioration
in the absence of UV.

Supplementary question - if cost was not an issue would
you get a new glider painted in PU or T35?

John Galloway