Dynaflite GPMA0090 Butterfly - Manual (Page 15)

15
❏ ❏
16. Roughly carve the wing tip with a razor
plane or a hobby knife. Final shape the tip and blend
it to W-15 with a bar sander and 150-grit sandpaper.
❏ ❏
17. Carefully remove any glue blobs and blend
all the ribs to the spars, TE and LE with a bar sander
and 220-grit sandpaper.
❏
18. Arrange the plan so the left outer wing panel
is on your building board, then cover it with wax
paper. Return to step 1 and build the left wing panel
the same way you built the right.
Don’t forget to
switch to the left wing panel plan so you do
not build two right panels.
Join the Inner Panels
Do not permanently join the inner wing panels, but
permanently install the joiner tubes so you can
temporarily join the panels for a days fl ying session.
Take the panels apart when it is time to go home.
❏
1. Thoroughly roughen the outside of the wing
joiner tubes with 150-grit sandpaper so the glue will
stick. Use a metal fi le or a powered hand tool with
a cut-off wheel to remove the burrs and chamfer
the ends of the 1/4" x 10-1/2" steel
wing joiner rod .
Remove any dirt or manufacturing oil from the rod
with a cloth dampened with alcohol or other solvent.
❏
2. Plug one end of both wing joiner tubes with a
piece of 3/32" or 1/8" leftover balsa, then carefully
glue the plug in position with a few drops of thin
CA. Do not allow CA to fl ow into the tube because
it may interfere with the joiner rod.
❏
3. Without any glue, temporarily join both inner
wing panels with the joiner tubes and the joiner
rod. Hold the wing halves together and inspect
the fi t between the W-1 ribs of the joining panels.
If necessary, separate the panels and use your bar
sander to adjust to the ends of the spars, LEs or
TEs so the W-1s fi t together well.
❏
4. With the joiner tubes and the joiner rod
in position, temporarily clamp the wing halves
together, then place a weight on one of the wing
panels to hold it down. Measure the height of the
outer W-4 from the building table. It should be
approximately 4-1/2".
❏
5. Remove your clamps, then position 1/8"
leftover balsa “spacers” between the W-1s and
clamp them together. The spacers will allow both
joiner tubes to protrude 1/16" from the inner panels.
❏
6. Use a stack of books, blocks of balsa or similar
to support the raised wing panel at W-4. Align the
joiner tubes so the ends meet in the center of
the wing and clamp the tubes to the shear webs.
“Spot-glue” the ends of the joiner tubes in each
wing panel with medium CA or epoxy.