Polly
Pusher
Study
the free Wally Wing plans since much of the construction is the same. Do the TEs and main spars the same before
cutting and joining the wing sections. You'll want some vertical doublers of
thin ply cut in later at the spar and TE joints to strengthen them. (Note for a
very light version - Not tried yet, but possible to make wings without any wood
TEs/spars and with sheet foam TEs and tail feathers for slow flyer with
light-weight power systems)
The
wing centers are joined (do first) with their TE straight in line as viewed
from the top, and the TOP center surfaces are flat (gives slight dihedral to
the center section since the wings taper in thickness) Just block it up till you can lay a straight
edge flat on the top at the max thickness point.
The
wing breaks are at 11 inches in from the tips measured on the LE. The tips are
sweep back at about 1 inch at the tip from the adjoining mid-section wing panel
LE line.
With
the center section of one wing flat on the table, the tip LE is raised 1.75 inches. The tip TE should be raised about 2 inches
for the built in washout. This results
in a slight off-set of the LEs where joined but won't show once taped. (request a pic from me if this doesn't make
sense).
Tail:
The CF booms are .254 dia. and are 20" long. 1/4" cable clamps hold them real snug. Go a little thinner if you want for weight
savings and to help with CG for light packs without having to add weight. There is thin-walled .230 diameter tubes
that should work but you'll have to put a little heat shrink or other shim
under the clamps to make them tight.
Arrow shafts and fiberglass kite rods can be used for the booms
also. Try to keep the tail as light as
possible however for easier CG balance later.
The
fronts of the booms end at the spar and they mount via either threaded spacers,
blind nuts in a small square of lite ply, or threaded wing mount block
etc. Glue whatever you use to the back
of the spar for strength and put a square piece of reinforcing tape over it
before taping the wings to keep it from pulling out.
You
can adjust the incidence of the tail here with nylon washers under the clamp if
needed, but mine just lays flat on the rear bottom of the wing and seems to
give enough. Rear clamps bolt through the center of the TE with thin ply on top
to reinforce the hole.
The
booms are spaced 11 in. apart. The tail
section is 18 in. "span" laying flat. (draw out on 1/4" =
1" graph paper to get layout if needed)
The
outside tail surfaces are 5" wide and the center is 3.5 in. including the
control surfaces. Control surface is 1.5" wide. Use the thinner type coroplast if available for tail weight
savings here also or better yet, sheet foam if going for a very light version.
Lay
it out so the webs of the coroplast run parallel to the hinge line. For the hinge, slice through one layer of
the coro between the webs. Take a
sliver out of that side between the webs to allow the other side to act as a
hinge and move freely.
For
the V bend, don't try to make the tail angle 90 degrees. It's much flatter than that. About a 6"
rise in the center. Cut a notch half
way through the bottom at the V center line and fold and tape for strength
along the fold.
The
rest you should be able to get from the pics.
Be sure that the tail gets mounted parallel to the booms so you don't
add any unknown incidence to deal with.
CG
it 2.5" back from the root LE of the wing and work your way back some. She
will bite bad if too far back.
Fuse
pod is 14.5 " long and about flush with the TE with the motor sticking out
a tad. See the Wally Wing plans for
mount details. Also, get the battery
pack as far forward as you can to keep from having to add nose weight.
Good
Luck!
Ken
Hill
Ace
Sim RC