WarbirdKits Boulton Paul Defiant Mk I Instructions for use

Boulton Paul Defiant Mk I
Manual Version 2.1 –January 2011
Scale: 1/15
Wingspan: 31.3 Inches
Area: 150 Square Inches
Power: 2408 Brushless
Original Design by David Collins

Boulton-Paul Defiant Construction Manual
Version 2.0 Page 2
PARTS LIST:
The builder will need to provide the following parts:
/”  ” X ” Balsa sheet  – Wing sheeting
/" X /" X ” Balsa stick (1) –Wing leading edge
/" X ” Balsa tiagle stok  – Fuselage
/” X ” Musi ie  – Ailerons, Elevator pushrod
/” ID X ” Aluiu tue  – Ailerons
/" X /” X ” Balsa stip  – Fuselage
/” X ” X ” Balsa sheet (1) –Fuselage sheeting
/” X ” Hadood doel  – Wing, Elevator joiner
Fiberglass Tape –Wing joint reinforcement
Self-tapping Screws –Cowl mounting
1/4" Square Hardwood –Cowl mounting
TRIM THE PLASTIC PARTS:
* Turret –.” tall.
* Cowl –.” fom spinner ring to rear of cowl. The cowl should overlap the
fuselage aout .”.
* Canopy –aout .” tall.
BALANCE
Balance the finished, read-to-fly model approximately 1-/” ehid the leadig
edge at the center of the wing. The balance point should be slightly ahead of the
front edge of the wing spar.
Glue the lower wings skins W1 thru W4 together. Sand both sides
smooth now. Do not glue the center and outer panels together.
Slot the ribs W5-W9 in to the slots in the spar W13 but do not glue yet.

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Lay down waxed paper and pin the center section sheeting to a flat
sufae. Net glue the /  /” leadig edge to the fot edge.
Glue the ribs and spar to the sheeting. Use a square to get the ribs
perpendicular to the spar and push the ribs up against the leading edge.
Glue the rib doublers W5A to each side of the center rib as shown.
Sand everything flush and smooth and try to get a bevel on the bottom
sheetig tailig edge to aout /” thik. Set the ete setio aside ad uild
the outer wing panels.

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Version 2.0 Page 4
Follow the same steps to build the outer wing panels. Be sure to build a
left and a right side.
Glue /” suae alsa stip to eah side of the slot. Pis i the edge of
the sheetig help to alig the spas. Thee ill e a /” gap etween them.
When the outer panels are finished pin the center section down followed
by the outer panels. Blok up the oute i /” as sho ad glue the paels
together.
Cut away some of the rib at the joint and glue some scrap 1/16 ply to
reinforce the dihedral break.

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Version 2.0 Page 5
Cut 4 each 1/2”lengths and 4 each 1/4”lengths of 1/16 aluminum or
plastic tubing (not included).
Cut a length of 1/16 music wire to 10-/” long. Bed up oe ed /”.
Slip on the tubing lengths /”-/”-/” as sho.
Bend the other end of the wire /” as sho. Make a left ad a ight
side.
Glue the tue eaigs to the is as sho. Do’t glue the eaigs to
the music wire!

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Version 2.0 Page 6
Glue a 1/4" piee of tuig oto the aileo. Do’t glue any of the tubes
to the wire!
Sheet the top of the ete setio ith /” alsa, a pape puh
makes neat holes for the aileron horn wire to protrude.
Sheet the oute paels ith /” alsa.
Cut the ailerons free from the underside. Sand the wing and aileron
flush.

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Version 2.0 Page 7
Use a scrap of /” ie to ake a hole i a stip of /” alsa. Glue the
strip to the aileron using the wire as a guide as shown.
Bevel the strip and notch for the aileron wire.
Hige the aileos to the ig usig /” stips of CA hige.
Glue the wing doublers F8 to the fuselage sides F7 using F2 to align them
as shown, Make a right and left side!

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Version 2.0 Page 8
Glue 1/4" balsa triangle to the aft bottom edges of the fuselage sides and
bevel the tail ends as shown.
Make up the battery box / motor mount.
Glue sap /” tiagle to the iside oes of the fieall as sho.
Using a square, glue F2 and F4 in position.

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Version 2.0 Page 9
Glue the other fuselage side in place.
Glue F1 to the battery box keeping it square.
Glue the battery box / F1 into the fuselage.
Glue F6 flush to the top of the fuselage sides.

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Glue scrap balsa to the underside of F6 to support it.
Glue F9 in place.
Laminate two F14 pieces together and glue in place. Glue some scrap
1/4" triangle into the inside corners for reinforcement.
Glue F5 in place and glue the fuselage sides together at the rear.