DuraPlane Trainer 40 User manual

DuraPlane
Champaign, IL
[phone], Ext. 5
[e-mail]
Assembly Instructions
Specifications:
Wingspan: 50 in (1270 mm) Weight: 5.25 lb (2380 g)
Wing Area: 500 sq in (32.3 sq dm) Engine Required: High-performance
Fuselage Length: 44 in (1117.6 mm) 2-stroke .40 to .46 cu in (6.5-7.5 cc) or
Radio Required: 4-Channel with 4 servos 4-stroke .48 to .51 cu in (7.86cc)
READ THROUGH THIS INSTRUCTION MANUAL BEFORE BEGINNING ASSEMBLY. IT CONTAINS
IMPORTANT INSTRUCTIONS AND WARNINGS CONCERNING THE ASSEMBLY AND OPERATION OF
THIS MODEL.
ENTIRE CONTENTS © Copyright 2003
Printed in USA DT40P03 for DURA1111 v1.1

The Trainer 40 is a great “dual purpose” model because it's
extra durable and simple to build for a beginner, and it builds
fast so experienced modelers can quickly get something in
the air if their primary model is out of commission. After you
move on to a fully aerobatic sport model, or get your best
model back into the air, the trusty Trainer 40 will still be
waiting in the wings for you to take it out and get in a few
relaxing flights. The “low risk” factor of the inexpensive, quick
building DuraPlane series makes them great test beds for
new radio equipment or breaking in new engines. Besides all
that, the Trainer 40 flies great and we're sure you'll enjoy lots
of smooth takeoffs and landings!
If this is your first model, the best way to learn to fly R/C is
to join a flying club. The Academy of Model Aeronautics is
the national organization that charters model clubs,
sanctions competitions and insures flying fields throughout
the United States. We urge you to join the AMA because
membership will bring you flying insurance, a subscription
to Model Aviation magazine and many other benefits. The
AMA will gladly send you membership information and lists
of AMA-chartered clubs in your area where you can seek
the help of experienced modelers.
Academy of Model Aeronautics
5151 East Memorial Drive
Muncie, Indiana 47302-9252
[phone]
FAX [phone]
Your hobby shop is also an invaluable place for service,
parts and information that you require. We urge you to
patronize your local hobby dealer – he’s there to help you
enjoy your hobby. Finally, if you have any questions or
comments about your DuraPlane, please write or call us at:
DuraPlane
3002 N. Apollo Dr. Ste. 1
Champaign, IL 61822
Telephone: [phone], Ext. 5
Fax: [phone]
E-mail: [email protected]
DuraPlane guarantees this kit to be free from defects in
both material and workmanship at the date of purchase.
This warranty does not cover any component parts
damaged by use or modification. In no case shall
DuraPlane’s liability exceed the original cost of the
purchased kit. DuraPlane reserves the right to change or
modify this warranty without notice.
This instruction manual provides step-by-step instructions
for assembling the Trainer 40 kit. Assembly of the Trainer
40 consists of eight major steps and must be completed in
the following order:
BUILD THE TAIL FEATHERS.......................Page 3
ASSEMBLE THE FUSELAGE.......................Page 5
RADIO INSTALLATION.................................Page 7
BUILD THE WING.........................................Page 9
COVER THE WING & TAIL SURFACES......Page 11
FINAL ASSEMBLY........................................Page 12
BALANCE THE MODEL................................Page 13
FINAL HOOKUPS & CHECKS......................Page 14
FLYING..........................................................Page 15
To assemble the Trainer 40, you need the following tools:
❏Flat blade and phillips screwdrivers
❏Small pliers (needle nose)
❏Hobby knife with #11 blades
❏Electric drill
❏Drill bits: 1/16", 7/64", 1/8", 5/32", #18 (or 11/64")
❏Hobby covering iron w/Hot Sock™– optional
(TOPR2175)
❏Sandpaper assortment and sanding block
❏Ruler & felt-tip pen
❏Masking tape
In addition to the parts included with the Trainer 40 kit, you
need the following accessories (we have had good success
using Great Planes®brand Adhesives and Accessory Items):
❏4-channel radio w/4 servos
❏.40-.46 2-stroke or .48 - .51 4-stroke engine w/muffler
❏Propellers (see engine instructions for size)
❏Top Flite®EconoKote®film - (1) roll
❏6-minute epoxy – (GPMR6045)
❏1 oz. thin CA – (GPMR6002)
❏Aliphatic resin (white glue) – optional (GPMR6160)
❏#6 x 3/4" engine mounting screws – (4) (GPMQ3030)
❏2-1/4" spinner (GPMQ4515)
❏8 oz. fuel tank – (GPMQ4103)
❏12" medium silicone fuel tubing – (GPMQ4131)
❏#64 rubber bands – (HCAQ2020)
❏5/32" wheel collars – (2) (GPMQ4306)
❏1/4" foam rubber – (HCAQ1000)
❏2-1/2" wheels – (3) (GPMQ4223)
❏3/4" wide fiberglass reinforced “strapping” tape
❏1/2" double-sided foam mounting tape (GPMQ4440)
❏1/16" x 5/16" wing seating foam tape (GPMQ4422)
❏Loctite®thread lock
Refer to the Parts List for a description of the parts and
hardware included with the Trainer 40 kit.
Accessories & Additional Items
Suggested Tools
Table of Contents
WARNING
Radio control models are intended for adults or use
under the close supervision of an adult. Flying model
airplanes can be dangerous and can cause serious
injury. DuraPlane assumes no responsibility for accidents
or injury caused by this product.
Introduction
2

❏1. Glue the shaped 1/4" balsa Fin Front to the Fin Rear
with medium CA. Use 150-grit sandpaper and a sanding
block to sand the Fin flat and round the leading edge
before proceeding. Glue the 1/4" x 1/2" x 5-7/8" balsa Fin
Base Sides to both sides of the Fin. Make sure that the
bottom of the fin and the bottoms of the fin base sides are
flush. Bevel the front of both fin base sides so they are
even with the LE of the fin.
❏2. Sand the Leading Edge (LE) of the shaped 1/4" balsa
Rudder to a “V” shape to allow for control movement.
Position a nylon Control Horn on the rudder so the bottom
edge of the horn is 7-1/4" below the top of the rudder. Use
the control horn as a template to drill two 1/16" holes for the
2-56 x 1/2" screws. Push the screws through the control
horn. Then thread them into the Control Horn Back Plate
until it is snug.
❏3. Mark the locations of the Hinges on the rudder and
fin as shown in the photo above.
❏4. Use a hobby knife with a #11 blade to cut the hinge slots.
Tip: Carefully move the blade back and forth to enlarge the slot
❏5. Cut the hinges from the 2" x 9" CA Hinge Strip, then
use scissors to snip the corners off. Test fit the hinges to
see if the slots are deep enough.
❏6. Temporarily join the rudder to the fin with three
hinges. Do not glue the hinges in the fin and rudder
until instructed to do so.
1"
1"
3/4"
AND #11 BLADE
WITH HOBBY KNIFE
CUT HINGE SLOT
Trim off the excess
screw threads
Assemble The Fin & Rudder
Build The Tail Feathers
3

❏1. Glue the shaped 1/4" balsa Stab Front to the Stab
Rear with medium CA. Tip: Sand the Stabilizer flat and
even before proceeding. Draw a centerline on the stab and
also on the 1/16" plywood Stabilizer Bottom Plate.
❏2. Align the centerlines. Then glue the stabilizer bottom
plate to the stabilizer. The end of the bottom plate should
be flush with the TE of the stabilizer. See the photo at step 3.
❏3. Sand the leading edge of the 1/4" balsa Elevator to a
“V” shape. Cut four hinge slots in the elevator and stabilizer
at the locations shown in the photo. Without using any
glue, temporarily join the elevator to the stabilizer with
four hinges.
❏4. Draw a line on the top of the elevator 6-7/8" from the
left tip. Align the left edge of a nylon control horn with the
line, then drill two 1/16" holes through the elevator – just
the same as you did on the rudder. Mount the control horn
to the elevator with two 2-56 x 1/2" screws and the back plate.
❏1. Drill two 1/8" holes through both sides of the rear of
the Aluminum Fuselage Channel at the locations shown
in the photo (the rear is the end with the two pre-drilled
smaller holes in the bottom that are closer together). Insert
the fin in the fuselage channel so that the trailing edge is
aligned with the aft edge of the channel. Mark the location
of the holes in the bottom and the sides of the fuselage
channel on the fin. Remove the fin and drill 1/8" holes
through only the marks on the side of the fin.
❏2. Center the black plastic stab incidence shim on the
fuse channel so that the aft edges are aligned. The thickest
part of the shim is the rear. Mark on the shim, the location
of the aft hole in the channel, then drill a 1/8" hole at the
mark in the shim.
❏3. Align the centerline you drew on the stabilizer bottom
plate with the holes in the fuselage channel and mark
their location.
Note: The TE of the stab should be aligned with the end of
the channel. Drill 1/8" holes through the stab at the marks.
Mount The Fin & StabAssemble The Stabilizer & Elevator
4

❏4. Use 6-minute epoxy to glue two 4-40 x 3/4" machine
screws in the bottom rear holes of the fuselage channel.
After the epoxy has cured, temporarily mount the stab to
the fuselage channel with the stab incidence shim, 4-40
screws, #4 washers and two 4-40 nuts.
Note: The bottom of the stab is the side with the 1/16"
plywood stabilizer bottom plate.
❏5. Remove material from the bottom of the fin as
needed to clear the heads of the screws, then temporarily
mount the fin to the fuselage channel with two 4-40 x 1"
machine screws and nuts.
❏1. Test fit your engine to the engine mount. If the engine
does not fit perfectly into the mount use a Dremel®
MultiPro™or a file to carefully grind away the plastic until
your engine drops into the mount.
❏2. Determine the location where the throttle pushrod will
exit the firewall portion of the engine mount so it will align
with the carburetor arm on your engine. For most engines
the molded-in hole on the upper right side of the mount is
close enough. Enlarge this hole with a 3/16" drill all the
way through the mount. If you decide to drill the hole in a
different location make sure the throttle pushrod will not
interfere with the fuel tank.
❏3. Place the engine on the mount, then mark the
location of the engine mounting holes. Drill 7/64" holes for
mounting the engine with #6 x 3/4" screws and washers
(not included). Some modelers prefer to drill and tap the
holes for 4-40 x 3/4" machine screws (not included)
instead. Use a #43 drill if you choose to tap threads for
4-40 screws.
❏4. Use a felt-tip pen to draw a line on the sides, top and
bottom of the fuselage 5/16" from the front edge. Fit the
engine mount into the fuselage, then drill two 7/64" holes,
evenly spaced, through the four sides of the fuselage and
the engine mount on the lines you drew. Make sure that
you do not drill the holes in a location that will interfere with
the throttle pushrod. Remove the mount, then enlarge the
holes in the fuselage only with a 9/64" drill.
Install the Engine Mount & Fuel Tank
Assemble the Fuselage
4-40 x 1" Machine Screw
4-40 Hex Nut
#4 Flat Washer
4-40 x 3/4" Machine Screw
5

❏5. Assemble a Great Planes 8 oz. fuel tank according to
the instructions included with the tank. Then install 6" of
medium fuel line on the fill and vent tubes. Cut a piece of
1/4" foam to a size of 3" x 8" and place it inside the front of
the fuselage about 1" back from the front edge. Slide the
tank into the foam inside the front of the fuselage. Mount
the engine mount to the fuselage with eight #6 x 3/4"
screws included with this kit, then slide the 12" long throttle
pushrod guide tube into the hole you drilled through the
firewall and past the fuel tank. Slide the 12" long throttle
pushrod into the guide tube. Mount the engine onto the
engine mount.
❏6. Place the fuselage on its side and use a 90-degree
triangle or a builder’s square to mark a line centered on the
forward hole in the bottom of the fuselage. Draw a line
across the center of each 1/4" plywood landing gear plate.
❏7. Fit a 8-32 x 1/2" screw through the hole in the center
of the aluminum landing gear and the forward hole in the
bottom of the fuselage. Align the outer holes in the landing
gear with the line you drew, then mark the locations of the
holes onto the fuselage bottom. Remove the landing gear,
then drill a 7/64" hole through the marks. Use coarse
sandpaper and a sanding block to round a bottom corner of
each landing gear plate so it will fit the curve inside the
fuselage. The bottom of the plates is the side with the line
you drew. Place one of the landing gear plates inside the
fuselage so the line is visible through one of the holes you
drilled, then mark the location of the hole on the landing
gear plate. Drill a 7/64" hole at the mark. Position, mark,
then drill a 7/64" hole through the other landing gear plate.
Mount the landing gear to the fuselage with the landing
gear plates and two #6 x 1/2" screws supplied with this kit.
The wood landing gear plates do not need to be glued to
the fuselage.
❏8. Remove the engine from the engine mount. Then
mount the wire nose gear to the engine mount with three
5/32" wheel collars and 6-32 x 1/4" screws included with
this kit. Insert one of the wheel collars into the nylon
steering arm. Arrange the wheel collars and temporarily
tighten the screws so the fuselage is level when sitting on
your workbench.
❏9. Drill the hub of the 2-1/2" main wheels with a #18 (or
11/64") drill, then fit a 8-32 x 1-1/4" “axle” into one of the
wheels and thread on a 8-32 nut. Screw the axle with the
wheel and nut onto the landing gear and secure it with
another 8-32 nut and a drop of thread lock. Mount the other
wheel to the landing gear in the same manner.
❏10. Mount the front 2-1/2" wheel to the nose gear with a
5/32" wheel collar (not supplied) on both sides of the wheel.
Mount The Landing Gear
6

❏11. Set the fuselage on your work bench and readjust
the wheel collars on the nose gear so the fuselage is level.
Secure the 6-32 screws in the wheel collars with a drop of
thread lock.
❏1. Use 6-minute epoxy to glue two 6-32 x 1/2" machine
screws in the front holes in the fuselage channel. Insert the
screws from inside the channel just like you did the 4-40
screws in the rear of the channel for the stab.
❏2. Insert three servos into the fuselage channel in the
orientation shown in the sketch. The front servo should be
approximately 3" from the front of the channel but should
not interfere with the 6-32 screw you glued in the channel.
The other servos should be behind the front servo but not
contacting each other.
❏3. Temporarily connect the servos and a battery pack to
the receiver. Then turn on the receiver and transmitter to
center the servos. Place a servo arm on each servo in the
orientation shown in the sketch, then turn off the system
and disconnect the servos.
❏4. Mount the receiver to the fuselage channel behind the
rear servo. There are a few ways to mount the receiver but
the most secure way, and the recommended way is to make
a receiver plate from a piece of 1/8" “lite-ply” and a piece of
3/4" wide balsa (not supplied). Glue the receiver plate (the
approximate size of the base of the receiver) to the balsa
block, then fit the block in the fuselage channel like you did
the servos. Mount the receiver to the plate with 1/4" of foam
in between the receiver and the plate. Make sure this
arrangement will clear the rear 1/4" wing dowel when it is
time to mount the fuselage channel to the fuselage.
❏1. Thread a nylon clevis onto a 1" threaded stud about
20 turns, then thread the other end of the threaded stud
about 1/2" into a 24" long Inner Pushrod Tube. Connect
the clevis to the control horn on the elevator. Route the
inner pushrod tube over the receiver and place it on top of
the elevator servo (middle servo) arm. Cut the inner
pushrod tube 7/8" short of the servo arm.
❏2. Cut a 24" Outer Pushrod Tube 2" shorter than the
inner pushrod and slide it over the tube. Thread another
clevis onto a threaded stud, then thread it into the inner
pushrod just the same as you did on the other end.
Temporarily connect the clevis to the servo.
Threaded Stud
Connect The Elevator & Rudder
Pushrods
RECEIVER
RUDDER
SERVO
THROTTLE
SERVO
ELEVATOR
SERVO
FUSE
CHANNEL
RX
BATTERY
FRONT
Install the Servos
Radio Installation
7

❏3. Perform the same operation for the rudder with the
same hardware you used for the elevator.
❏4. Secure the front end of the elevator and rudder outer
pushrod tubes by taping them directly to the receiver.
Tip: Place a 3/16" x 7/8" x 1-1/2" balsa block (not included)
between the pushrods.
❏5. Temporarily tape the aft end of the outer pushrod
tubes to the fuselage channel in the area about 1" ahead of
the stabilizer.
❏1. Connect a clevis using a 1" threaded stud to one of
the 12" throttle pushrod. Slide the pushrod into the throttle
outer guide tube from inside the fuselage.
❏2. Temporarily mount the fuselage channel to the
fuselage with a 6-32 nut on both of the 6-32 screws you
glued to the channel. Mount the engine if you have not
already done so.
❏3. Connect the clevis on the throttle pushrod to the
throttle servo arm. Thread a 1" threaded stud onto a clevis,
then temporarily connect the clevis to the arm on the
carburetor. When the clevis and the threaded stud are
connected to the carburetor, you can see where to cut the
outer guide tube and the throttle pushrod. Cut the tube and
pushrod, then disconnect the clevis from the carburetor
and thread the stud into the throttle pushrod.
❏4. Now that the pushrods are connected and the exact
location of the servos is determined, attach the servos
securely to the aluminum fuselage. Wrap two layers of
reinforced filament tape around the servos and the fuse
channel the same as we recommended for the receiver.
❏1. Thread a 1" threaded stud with a clevis into the 36"
long inner pushrod tube, then slide it into an outer pushrod
tube cut to a length of 35". Connect the clevis to the rudder
control horn next to the other clevis from the rudder servo.
Remove the tape from Step 5, then tape all three pushrod
tubes to the fuse channel.
❏2. Install two Pushrod Hold Down Clamps on the outer
pushrod tube and position them on the bottom of the
fuselage at the approximate location shown in the photo in
the following step. Do not drill into the fuel tank,
receiver, receiver battery or other equipment. Drill two
7/64" holes through the bottom of the fuselage. Then use a
#6 x 1/2" screw to fasten each nylon clamp to the fuselage.
Connect The Nose Wheel
Connect The Throttle Servo
8

❏3. Cut the inner pushrod tube to the correct length, then
install the last 1" threaded stud with a clevis. Position the
steering arm as shown in the photo. Adjust the length of
the pushrod so that when the rudder is neutral and the
pushrod is connected to the steering arm, the nose wheel
is also neutral.
❏4. Turn the model over and confirm the coordination of
the rudder and the nose wheel – when the rudder moves
left, the nose wheel should turn left.
❏1. Apply a thin film of aliphatic resin (white glue such as
Great Planes Pro) or epoxy to one of the wing tips and the
root of one of the wing extensions then join the two pieces
by clamping them together with T-pins and masking tape.
Hint: Stick the T-pins in first as they will keep the root
extension from shifting while you apply the masking tape.
Place a straightedge on the bottom of the wing across the
wing and the wing extension to make sure you have not
inadvertently built in some dihedral or anhedral to the tip of
the wing.
❏2. Glue the other wing extension the other wing tip in the
same manner. Allow the glue to fully dry before proceeding.
❏3. Use a hobby knife or a MultiPro to cut the hole in the
plastic wing shield for the aileron servo. True the sides of the
wing shield with a bar sander and 220-grit sandpaper.
❏4. Place the wing shield on the wing and aligning the
hole in the shield with the hole in the wing for the aileron
servo. Use a felt-tip pen to mark the edges of the wing
shield onto the trailing edge of the wing.
❏5. Cut the 1/4" x 5/16" x 24" balsa wing trailing edges so
they fit between the marks you made and the tip of the
wing. Use epoxy or aliphatic resin to glue the trailing edges
to the wing and hold them in position with masking tape
until the glue dries.
Note: The 1/4" side of the trailing edges is the side that
gets glued to the wing.
❏6. Use a sanding block to sand the ends of the balsa
trailing edges so they are flush with the wing tips.
❏7. Optional: Trace the outline of both wing tips onto a
1/8" balsa sheet (not included), then cut the wing tips from
the sheet and glue them to the tips of the wing. After the
glue dries use a sanding block and 220-grit sandpaper to
shape the balsa tips to match the contour of the wing. The
1/8" balsa will add a little durability by protecting the wing
tips from dents and dings.
Assemble the Ailerons
Build The Wing
9

❏8. Trim one of the 1/4" x 1" x 24" balsa ailerons so it
extends from the left wing tip to the line you drew indicating
the left edge of the wing protector. Mark the location of the
hinge slots on the trailing edge of the wing and the left
aileron according to the measurements shown in the photo,
then cut the hinge slots in the wing and the aileron the
same way you did for the rudder and elevator. Perform the
same procedure for the right aileron.
❏9. Use a razor plane or a bar sander and 150-grit
sandpaper to shape the leading edge of the ailerons to a
“V” to allow for control movement. Test fit the ailerons to
the wing with eight hinges cut from the hinge strip.
❏1. Drill or cut a hole through the wing to allow the aileron
servo cord to pass, then test fit your servo in the wing so
the output shaft is forward. Make adjustments if required,
then use 6-minute epoxy to glue the 1/8" plywood servo
mounts in the wing. Hint: Use a piece of 1/4" brass tube
sharpened at one end to make the hole in the foam for the
servo cord.
❏2. Fit the aileron servo into the wing, then drill two 1/16"
holes in both servo mounts for the servo screws included
with your radio system. Mount the servo to the servo
mounts.
❏3. Thread a clevis about 20 turns onto a 12" wire
pushrod, then cut 4" off the other end. Connect the clevis
to the third from the outer hole of a control horn. Make
another pushrod assembly the same way.
❏4. Make a 2-armed servo arm by cutting the opposite
arms off a 4-armed servo arm. Place the arm on your
aileron servo, then position one of the pushrod assemblies
on the wing so the control horn is 1/4" from the end of the
aileron and the pushrod aligns with the middle hole of the
servo arm. Mount the control horn to the aileron with two
2-56 x 1/2" screws and the control horn back plate the
same way you did for the elevator and the rudder. Mount
the other control horn to the aileron in the same manner.
❏5. With the ailerons in neutral position, use a felt-tip pen
to mark both pushrods where they cross the holes of the
servo arm, then use pliers to make a 90-degree bend at
each mark. Temporarily connect a nylon Faslink to the
pushrods, then cut the pushrods so only about 1/16" of
2-56 (.074")
Pushrod Wire
Servo Horn
FasLink 1/16"
CUT OFF
SERVO ARM
CUT OFF
SERVO ARM
Hook Up the Ailerons
10