All,
Recently a message was posted regarding filling and
the difficulty of getting rid of the pin holes unless
one used a more wet Expancell mix, even though this
might add a little weight. But how much will be
added?
I did a quick measurement this afternoon of the
specific gravity of wet Expancell (like a medium thick
syrup, running fairly easily) and "dry" (almost
standing up on the mixing stick) mixed into Aeropoxy:
- Aeropoxy with hardener only: Sp. g. 1.11
gram/cu.cm.
- Wet Expancell mix: Sp. g. 0.62
- Dry Expancell mix: Sp. g. 0.47
Assuming that the wet mix is used instead of the dry
mix in a 1 mm thick layer(comparison for those not
intimate with metric units: the skin of the flaps is
0.8-0.9 mm thick), and further considering this
applied on the rudder, stabilizer/trim tabs, ailerons
and flaps, the total weight difference is approx. 1.25
kg or 2.8 lbs.
The real weight increase would probably be even less
due to thinner layer than 1 mm required to avoid the
pin holes and also a drier (lighter) mix could perhaps
be used than the "wet" used in the above example.
Of course bad to carry all this weight forever
after, but if I am able to get in the air earlier - -
-
Happy filling!
Svein #A225
http://promo.yahoo.com/videomail/
|