Flight Video is at;https://www.youtube.com/watch?v=rDfcimUYEP8&feature=youtu.beFlight Report below at post #47Christmas is over and the forecast is heavy snow.
Good time to build something !
My previous posts about building the
Cox Spitfire Replica and the Top-Flite
Form-Flite P-47 show my enthusiasm
for molded 1/16" balsa. It's light , stiff,
crash resistant and straight forward.
Check out those posts for the details
about molding.
The Focke Wulf 190D is a perfect subject
for this technique. I've decided to build a
stunter but a scale FW-190 would be even
easier.
The first picture shows the concept
drawing and the plug.
I have always found conceptualizing
with a pencil let's me think more freely
so since the fuselage is more sculptural
I just nail down the dimensions then
have fun making it pretty.
Carving the forms to mold the fuselages
is simple. I just use lots of pencil lines,
carve a little, then more pencil lines,
sand and more pencil lines.
Nothing fancy.
Notice that the bottom of the plug is flat
and straight at the wing root. This gives
me a datum line so that I can set the
incidences at 0-0-0.
The other thing I've learned is to
NOT cut out details like the cockpit and
wing/stab mounts from the plug.
It makes molding the wet 1/16" impossible.
So the big deal here is the wing.
It didn't take much addition to realize that
a 1/2A stunter with 210 sq/inch wings
has to be super light if a Cox .049 is
going to pull it.
Looking at Other designs (Thanks Larry!),
12oz. has to be the absolute maximum.
I have considered everything. Foam, Foam board,
traditional built up, Millennium, I-beam and even
(very briefly ) Coroplast.
What I have decided on is a molded "D-tube"
like a Nobler but without a traditional leading edge.
The picture says it all.
I used the "Blend" tool in Adobe Illustrator
to generate the NACA 15 wing ribs.
Just draw the root foil and tip foil and...
Push the button Max!
A technique I have used constantly for many
years is to design everything in CAD and then
print it out and glue the paper to the balsa.
Keep the #11 sharp, cut to size then sand to
the printed outline.
The parts I hand cut are amazingly accurate.
Everything fits together like magic.
The pictures show how the molded leading
edge fits accurately over the ribs and the
main spar. It is tight and straight!
The trailing edge will be carbon rod salvaged
from Brad Lapoint's combat casualties.
God bless those Russians!
More to come.. - K