Gelcoat repair

Jim Phoenix reads RAS from time to time, so I'll try not to tell
any
lies. *I corresponded with him quite some time ago, about the time I
was re-finishing a small portion of my fuselage with gelcoat.
Regarding the gelcoat vs poly, *I'm pretty sure he said if he had it
to do over again, he wouldn't gelcoat, he'd shoot polyurethane.- Hide quoted text -


Yup, I still believe that. Gelcoat is very forgiving for the amateur
(like me), but I was shocked at how much weight it adds, and when done
poorly, you can add a lot of weight covering up bad spray jobs. Flight
controls expecially get heavy with gelcoat and I ended up shooting the
elevators on the Nmbus with polyurethane because I couldn't get them
mass balanced within limits - very frustrating. If I had to do it
again, I would do the gelcoat removal and sanding and profiling and
priming myself then have a pro shoot on the polyurethane. Polyurethane
is dangerous if not applied in a proper envirnment due to it's
hazards.

With regard to Bob K.s reading of part 43, he's right - almost... 43.1
applicability reads "This part does not apply to any aircraft for
which the FAA has issued an experimental certificate, unless (here's
the fun part) the FAA has issued a different kind of certificate for
that aircraft [Amend #39, eff. 01 SEP 2004].

So what that means is that if your glider was a TC'd model with a
standard airworthiness issued and you somehow got an experimental
certificate for it later, well then part 43 does apply to you. Sounds
kinda crazy I know, but it's happened in the GA world - but is much
more prevalent in the air carrier world when STC developers need to
take a TC'd aircraft and put it into experimental R&D or some such
thing while they perform test flights to satisfy the FAA, then the
aircraft goes back to Standard Airworthiness after the test flights
are done and the STC is approved - bottom line is that 43 continues to
apply throughout the experimental life of the project. Too much info
probably, but hey there ya go.

Jim