In my opinion the wobbling of the spinner could be due to the
feebleness of
the spinner fiberglas bulkheads. This causes that any small
eccentricity or
imbalance gets amplified dynamically and originates strong vibrations.
I have had the opportunity to make the dynamic balancing of the
propeller.
Without spinner the vibrations were into the normal range but with the
spinner the vibrations were absolutely inadmissible. This fact
surprised me
because, in static, the spinner eccentricity was only about 1.5 mm
measured
at 120 mm from top, which does not looks like too much. In any case we
solved the problem by adding about 25 g of adhesive lead in some point
in
the interior of the spinner.
I think that all will be easier is the spinner bulkhead were in
aluminium as
they are in other aircraft with fiberglas spinners (yak, sukoi).
Best regards
Javier Barahona
#187 Classic
-----Mensaje original-----
Enviado el: mi=E9rcoles 27 de septiembre de 2000 22:24
Para: europa@avnet.co.uk
One of my first impressions of the Europa, way back in the earliest
days
when G-YURO was the only one in existence, was that when the engine was
started, the spinner didn't spin, it wobbled. Now that I'm trying to
fit
the spinner I can see why.
Most of the completed Europas that I've seen since have been at
Cranfield with their engines stopped so I don't know whether wobbly
spinners is still a general problem or not.
I have a VERY early Mk 1 kit (No 26), if any other early pioneers could
give me a hint on how to make the spinner run true I'd be very
grateful.
Thanks
Graeme Smith
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