Top Flite TOPA0410 - Manual (Page 41)

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BUILD THE MIDDLE FLAPS
❏ ❏ 1. Glue two of the die-cut 1/4" [6.4mm] balsa middle
flap LE’s together to make a 1/2" [12.7mm] thick flap LE.
❏ ❏ 2. Tack glue a leftover piece of 1/16" [1.6mm] plywood
and a 1/8" [3.2mm] plywood flap end to the inboard end of
the outboard flap and the outboard end of the inboard flap.
❏ ❏ 3. Sand the ends of the middle flap LE so that it fits
between the inboard and outboard flaps. Also, sand the
flap LE to match the sweep of the wing TE and the taper
of the wing top and bottom.
❏ ❏ 4. Position the middle flap LE over the plan and mark
the rib locations.
❏ ❏ 5. Place a piece of wax paper or Plan Protector over
the plywood flap ends on the inboard and outboard flaps.
Tack glue the LE between the inboard and outboard flap
and glue the die-cut 1/8" [3.2mm] balsa flap ribs to the LE.
❏ ❏ 6. Make a bottom middle flap skin from a 3/32" x 3"
x 30" balsa sheet. Note the fore and aft grain direction.
Taper the aft edge of the skin to match the angle of the
flap ribs. Glue the skin to the middle flap frame.
❏ ❏ 7. From the 1/2" x 1/2" balsa stick, cut 3/4" [19mm]
long hinge point backups and flap torque rod blocks. Glue
the blocks on the back of the LE, end ribs and bottom skin.
Sand the flap torque rod blocks flush with the end ribs.
❏ ❏ 8. Make a top middle flap skin from the remaining
3/32" x 3" balsa sheet. Again notice the fore and aft grain
direction. Glue the skin to the middle flap frame.
❏ ❏ 9. Sand the top and bottom flap skin flush with the LE
and both end ribs.
❏ ❏ 10. Break loose the die-cut 1/8" [3.2mm] plywood flap
ends from the inboard and outboard flaps. Drill a 3/32"
[2.4mm] hole through the flap end ribs at the forward
punch marks only. Glue the plywood flap ends to the ends
of the middle flap, aligning the front of the plywood flap
end and the LE. The larger radius LE on the flap end goes
toward the bottom of the flap.