I would like to second the comments below.
Having experience with 3 projects, the last one I did in PU. The
results were out standing, even though the spraying was done in a home
made spray both , 11ft x 34ft with a 1HP exhaust fan and fresh
filtered air coming into the spray both. The unsanded final finished
would have been ok too. But the miniscule orange peel effect is just
not exceptable to glider pilot, hence it was sanded and polished too
a nice finished.

The PU I used is the same that is used an all Bombardier Jets.
The sanding primer that goes along with it allow for very easy and
controlled sanding without plugging the sanding pad. I also used the
primer in a squeegee process on the wing. Only when I was happy with
the accuracy of the surface did I spray on the first primer coat,
sanded it and spray a second one and sanded it as well with dye, to
control the sanding process. I also sanded the finished product with a
dye as a guide.

I also had good experience with the Polyester Product.
If you go that route, use a very good tooling gel and mix it with
20%-25% Dura Tech, it transforms the gel coat into a paint like
product.
Most importantly it prevent cracking and protects it from the sun.
I finished 2 gliders like that, they are still flying with all there
glory after 15 years, one was a St.Cirrus. The second one, only has
about 12 years on it. The gel coat is heavier, it needs to be, as it
does not hide as well.
Udo


On Jan 8, 2:11*pm, wrote:
I finished a Silent 2 Targa kit this past fall and used the Loehle
Aero Coatings which is a two-part poly formulated for aircraft. *To be
sure, there is a tremendous amount of work involved in achieving a
good finish, but the Loehle covering process worked as advertised. *I
did use a pricey HVLP spray system that pumped fresh air along with
air for the gun, in deference to the toxicity of this type of
covering. *The point of my response here is to say that I did both
sand and polish the two-part poly, to an excellent shine. *It was hard
work, but the results are quite satisfying. *I'm happy to send a photo
and correspond with anyone who is contemplating using this product.
(I'm not on commission!)

Mike Hostage
Norfolk, VA