Great Planes GPMA0156 User Manual

WARRANTY

Great Planes Model Manufacturing Co.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 Great Planes’ liability exceed the original cost of the purchased kit. Fur ther, Great Planes reserves the right
to change or modify this warranty without notice.

In that Great Planes has no control over the final assembly or material used for final assembly, no liability shall be
assumed nor accepted for any damage resulting from the use by the user of the final user-assembled product.By the act
of using the user-assembled product, the user accepts all resulting liability.

If the buyers are not prepared to accept the liability associated with the use of this product,they are advised
to return this kit immediately in new and unused condition to the place of purchase.

READ THROUGH THIS INSTRUCTION MANUAL
FIRST. IT CONTAINS IMPORTANT INSTRUCTIONS
AND WARNINGS CONCERNING THE ASSEMBLY
AND USE OF THIS MODEL.

CUB1P05 V1.0 Entire Contents © Copyright 2000

P.O.Box 788 Urbana, IL 61801 [phone]

[e-mail]

INSTRUCTION MANUAL

TM

USA

MADE IN

IMPROVED

SAFETY PRECAUTIONS. . . . . . . . . . . . . . . . . . . . . . . . 2

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

IF YOU’RE NEW TO ELECTRICS. . . . . . . . . . . . . . . . . . 3

Keep it Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

DECISIONS YOU MUST MAKE . . . . . . . . . . . . . . . . . . . 3

Radio Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Motor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Battery Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Chargers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

PREPARATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Required Accessories . . . . . . . . . . . . . . . . . . . . . . . 4

Power Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Building System. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Optional Supplies & Tools . . . . . . . . . . . . . . . . . . . . 5

Common Abbreviations . . . . . . . . . . . . . . . . . . . . . . 6

Types of Wood. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Metric Conversions . . . . . . . . . . . . . . . . . . . . . . . . . 6

Important Building Notes . . . . . . . . . . . . . . . . . . . . . 6

Die Patterns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

BUILD THE TAIL SURFACES. . . . . . . . . . . . . . . . . . . . . 8

Build the Fin and Rudder . . . . . . . . . . . . . . . . . . . . . 8

Build the Stabilizer and Elevator. . . . . . . . . . . . . . . . 8

Finish the Tail Surfaces . . . . . . . . . . . . . . . . . . . . . 11

BUILD THE WING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Build the Wing Panels . . . . . . . . . . . . . . . . . . . . . . 11

Join the Wing Panels . . . . . . . . . . . . . . . . . . . . . . . 14

Assemble and Install the Wing Tips . . . . . . . . . . . . 15

Build the Ailerons . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Finish the Wing . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

BUILD THE FUSELAGE. . . . . . . . . . . . . . . . . . . . . . . . 19

Assemble the Fuselage Sides . . . . . . . . . . . . . . . . 19

Join the Fuselage Sides . . . . . . . . . . . . . . . . . . . . . 21

Sand the Fuselage. . . . . . . . . . . . . . . . . . . . . . . . . 27

Mount the Wing . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Mount the Stabilizer and Fin. . . . . . . . . . . . . . . . . . 29

Install the Dowel Stringers . . . . . . . . . . . . . . . . . . . 30

Mount the Landing Gear . . . . . . . . . . . . . . . . . . . . 31

Build the Motor Mount . . . . . . . . . . . . . . . . . . . . . . 32

Mount the Cowl . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Construct the Wing Struts . . . . . . . . . . . . . . . . . . . 34

RADIO INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . 34

Mount the Servos. . . . . . . . . . . . . . . . . . . . . . . . . . 34

Install the Nylon Control Horns . . . . . . . . . . . . . . . . 35

Make the Pushrods . . . . . . . . . . . . . . . . . . . . . . . . 35

BALANCE THE AIRPLANE LATERALLY. . . . . . . . . . . 37

FINISHING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Final Sanding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Covering the Model . . . . . . . . . . . . . . . . . . . . . . . . 37

Painting Your Model . . . . . . . . . . . . . . . . . . . . . . . . 38

FINAL HOOKUPS AND CHECKS . . . . . . . . . . . . . . . . 39

Install the Hinges. . . . . . . . . . . . . . . . . . . . . . . . . . 39

Install the Wheels. . . . . . . . . . . . . . . . . . . . . . . . . . 40

Install the Plastic Parts. . . . . . . . . . . . . . . . . . . . . . 40

Install the Motor Battery. . . . . . . . . . . . . . . . . . . . . 41

Reinstall the Radio System . . . . . . . . . . . . . . . . . . 41

BALANCE YOUR MODEL . . . . . . . . . . . . . . . . . . . . . . 42

FINISH THE RADIO INSTALLATION . . . . . . . . . . . . . . 43

INSTALL THE WING STRUTS . . . . . . . . . . . . . . . . . . . 43

SET THE CONTROL THROWS . . . . . . . . . . . . . . . . . . 44

PROPER CARE OF YOUR MOTOR . . . . . . . . . . . . . . . 44

PERFORMANCE TIPS. . . . . . . . . . . . . . . . . . . . . . . . . 45

PREFLIGHT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Charge the Radio Batteries . . . . . . . . . . . . . . . . . . 45

Balance the Propeller. . . . . . . . . . . . . . . . . . . . . . . 45

Find a Safe Place to Fly . . . . . . . . . . . . . . . . . . . . . 46

Ground Check the Model . . . . . . . . . . . . . . . . . . . . 46

Range Check Your Radio . . . . . . . . . . . . . . . . . . . . 46

AMA SAFETY CODE. . . . . . . . . . . . . . . . . . . . . . . . . . 46

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Radio Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

FLYING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Takeoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Flight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Landing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

2-VIEW DRAWING. . . . . . . . . . . . . . . . . . . . . back cover

Your ElectriCub is not a toy, but rather a sophisticated,
working model that functions very much like an actual
airplane. Because of its realistic performance, the
ElectriCub, if not assembled and operated correctly,
could possibly cause injury to yourself or spectators and
damage property.

To make your R/C modeling experience totally
enjoyable, we recommend that you get experienced,
knowledgeable help with assembly and during your
first flights.You’ll learn faster and avoid risking your model

before you’re truly ready to solo.Your local hobby shop has
information about flying clubs in your area whose
membership includes qualified instructors.

You can also contact the national Academy of Model
Aeronautics (AMA), which has more than 2,500 chartered
clubs across the country. Through any one of them,
instructor training programs and insured newcomer training
are available. Contact the AMA at the address or toll-free
phone number below.

Academy of Model Aeronautics

5151 East Memorial Drive

Muncie, IN 47302-9252

Tele. [phone]

Fax [phone]

or via the Internet at http://www.modelaircraft.org

PRO TECT YOUR MODEL,Y OURSELF

& OTHERS...FOLLOW THESE

IMPORTANT SAFETY PRECAUTIONS

TABLE OF CONTENTS

2

1. Build the plane according to the plan and instr uctions. Do
not alter or modify the model, as doing so may result in an
unsafe or unflyable model. In a few cases the plan and
instructions may differ slightly from the photos. In those
instances the plan and written instructions are correct.

2.Take time to build straight, true and strong.

3. Use an R/C radio system that is in first-class condition,
and a correctly sized motor and components (batteries,
wheels, etc.) throughout your building process.

4.You must properly install all components so that the model
operates properly on the ground and in the air.

5.You must check the operation of the model before every
flight to ensure that all equipment is operating and that the
model has remained structurally sound. Be sure to check
nylon clevises or other connectors often and replace them if
they show signs of wear or fatigue.

Remember:Take your time and follow directions to end
up with a well-built model that is straight and true.

Please inspect all parts carefully before starting to
build! If any parts are missing, broken or defective, or if
you have any questions about building or flying this
airplane, please call us at:

[phone]

or e-mail us at:

[e-mail].

If you are calling for replacement parts, please
reference the part numbers and the kit identification
number (stamped on the end of the carton) and have
them ready when calling.

Since the original ElectriCub was introduced in 1987, electric
airplanes have grown in popularity and so has the technology.
Over the years modelers have told us what they would like to
see different on the ElectriCub. We've been listening! The
redesigned ElectriCub now comes with ailerons, clear windows
and is designed for mini servos.We've done extensive testing
of motors, gearbox es and props to find the best combination, at
the lowest price, for the new ElectriCub.

While the ElectriCub is easy to fly, it does not have the total
self-recovery and stability of a basic trainer like the Great
Planes series of PT basic trainers. Therefore, if you have
never flo wn an R/C airplane before , we strongly recommend
that you seek out the assistance of an experienced R/C pilot
who will be able to check out your construction and help you
with your first flights.We do know that once you have flown
the ElectriCub you will want to keep it in your vehicle for that
quick flight during your lunch break or to relax with a few
flights after work.

Keep It Light

Because the electric motor and motor battery are relatively
heavier than a glow engine, it is essential that the basic
structure of the airplane be kept as light as possible. In
doing so, you will help insure that the finished airplane will
not be too heavy to fly well.

One way to pre vent excess weight build-up is to use only as
much glue as needed for a good glue joint. Do not apply
extra “fillets” of glue thinking that it will make your plane
stronger! Extra glue could possibly add ounces to the
weight of your plane and detract from the performance.

We will give you tips throughout this book on how to keep
the structure light and we urge you to follow them.

Radio Selection

Because weight is an important factor in the ElectriCub,
the ideal radio system is one that has a miniature
receiver, three mini servos such as Futaba®’s S3101
servos and an electronic speed control with BEC (Battery
Eliminator Circuitry such as the Great Planes Speed 300
GPMM2030). The electronic speed control with BEC
uses the motor battery , not a separate receiv er battery, to
power the receiver and servos. When the motor batter y
voltage reaches a preset voltage, the BEC on the speed
control stops the motor while still supplying power to the
receiver and servos.This setup can reduce the weight of
the plane by as much as 4 oz. However, the ElectriCub
will fly great with four mini servos, a 270 mAh receiver
battery and a micro switch. This setup is a great,
inexpensive way for the first-time electric pilot to try
electric flight. Once you’re hooked on the clean and quiet
advantages of electric flight, you can replace the micro
switch with a high quality electronic speed control.

DECISIONS YOU MUST MAKE

IF YOU'RE NEW TO ELECTRICS

INTRODUCTION

NOTE: We, as the kit manufacturer, provide you with a
top quality kit and great instructions, but ultimately the
quality of your finished model depends on how you build
it; therefore, we cannot in any way guarantee the
performance of your completed model, and no
representations are expressed or implied as to the
performance or safety of your completed model.

SAFETY PRECAUTIONS

3

4

Items in parentheses (GPMQ4243) are suggested part
numbers recognized by most distributors and hobby shops
and are listed for your ordering convenience. GPM is the
Great Planes brand, TOP is the Top Flite®brand, HCA is the
Hobbico®brand and COV is the Coverite™brand.

❏ 4 Channel radio with 4 mini ser vos
❏ (2) 2" Ultralight Wheels (GPMQ4201)
❏ (1) 3/4" Tail wheel (GPMQ4240)
❏ (4) 1/8" Wheel collars (GPMQ4304)
❏ (1) 1/16" Wheel collar (GPMQ4300)
❏ (1 Roll) Double-Sided Foam Tape (GPMQ4440)
❏ (1) 1/6 Scale Pilot
❏ (2) Rolls covering film
❏Motor battery pack charger 900 AC/DC Charger (HCAP0125)

or 925 AC/DC P eak Detection Charger (HCAP0198)

❏ 1700mAh 8.4 volt NiCd battery pack (DTXC2071) or

2000mAh 8.4 volt NiCd battery pack (DTXC2076)

Required Accessories

PREPARATIONS

Chargers

A fully charged battery pack will provide an initial “surge”
of power during the first 15 to 30 seconds of the motor
run.Then the power output stays fairly steady for the next
several minutes before dropping off quickly. If you do not
charge your battery completely, it will not deliver that
surge necessary for a good takeoff and climb out.There
are three easy ways to “peak-charge” your battery pack.

1. The easiest way is with a “peak-detecting” battery
charger. This type of charger will automatically charge
your battery until it is fully charged.

2.The second method of charging your motor batteries is
to monitor the voltage of your battery pack with a
voltmeter.Your charger may have sockets into which you
may plug a voltmeter. If not, you may insert the probes
from the voltmeter into the rear of the battery plug,
making contact with the metal contacts. As your battery
charges, the voltage will gradually increase. When the
battery is fully charged, the voltage will start to drop.At
this point your battery is fully charged.

3.The third (and least reliable) method of “peak-charging”
your battery pack is by checking its temperature. As the
battery charges it will remain cool until it is fully charged.
When it reaches the fully charged state, it will rapidly
build up heat.You can feel this heat with your hand. As
soon as the pack starts to noticeably warm up,
disconnect it from the charger. Do not continue
charging if the battery pack is hot! Overcharging will
damage your battery pack and can result in an explosion.

Motor Selection

In testing the ElectriCub, many different motors were
evaluated. Some of them provided adequate thrust to fly
the ElectriCub satisfactorily. Some, however, gave such
marginal performance that the climb-out was very shallow
and flight times were short. Generally, a high perf ormance,
high power motor , like the Great Planes S-600™direct drive
motor, will give the ElectriCub a good climb rate and good
aerobatic capability, but will result in a relatively short run
time of 3 to 4 minutes.

The Great Planes T600r™reverse rotation motor with a

2.5:1 gear drive unit enables the motor to turn a larger,
more efficient propeller at a slower speed. This usually
results in more thrust for a better climb rate and longer
flight times up to 8 minutes. We consider this motor and
gear drive combination (GPMG0760) to be the system of
choice for the ElectriCub.See “Power Systems”on page 5.

Battery Selection

The ElectriCub was designed to fly on a 7-cell 8.4 volt
1700 - 2000 mAh flat battery pack. Even though the
ElectriCub will fly well on an inexpensive motor battery
pack, we recommend a battery pack that uses Sanyo®or
Panasonic®cells. These cells have a low internal
resistance which translates into more power and less heat.

If you are new to electric airplanes (or even cars and
boats) here is a short explanation of NiCd batteries. A
single cell NiCd battery supplies 1.2 volts with no load (not
powering anything). A 7- cell battery pack can supply 8.4
volts (1.2 volts x 7 cells = 8.4 volts).The cell rating in mAh
(milli-amp-hours) is the amount of current the battery can
supply. If a battery is rated at 1700 mAh, the battery can
supply 1.7 amps for 1 hour (or 1 amp for 1.7 hours).This
sounds great – flying for over 1-1/2 hours on a single
battery charge! The bad news is that to produce the power
needed to fly an airplane the size of the ElectriCub, the
motor draws from 15-25 amps. The current consumption
reduces the run time to 4-6 minutes.The good news is that
propellers become more efficient as the speed of the plane
increases.This lowers the current draw, allowing the plane
to fly longer on a single charge, sometimes up to 20%
longer. Also, if an electronic speed control is used, the
motor can be throttled back, increasing the flight time.Most
airplanes only need full throttle during takeoff.

We recommend the use of high quality battery packs.The
higher quality batteries usually have less internal resistance
than the average battery. The higher quality battery will
provide more power to the motor than the average battery.
In NiCd batteries, internal resistance transforms power into
heat. With less internal resistance, there is more power
available to the motor and less heat is generated.We hope
this helps explain NiCd batteries and why a high quality
battery should be used in the ElectriCub.

Power Systems

Good: GPMG0755 S-600 Motor System

S-600 motor (GPMG0710)
8 x 4 propeller
Propeller adapter
Wiring harness with fuse and micro switch

Better: GPMG0760 T600GD System with Gear Drive

T600R reverse rotation motor (GPMG0700)

2.5:1 gearbox (GPMG0850)
Propeller adapter (GPMG0855)
10 x 8 propeller for electrics
Wiring harness with fuse and micro switch

Best: GPMG0760 T600GD ESC System with Gear Drive

and electronic speed control

T600r reverse rotation motor (GPMG0700)

2.5:1 gearbox (GPMG0850)
Propeller adapter (GPMG0855)
10 x 8 propeller for electrics
Speed 300 Electronic speed control with BEC and
auto cutoff (GPMM2030)

These are the building supplies that are required. We

recommended Great Planes Pro™CA and Epoxy glue.

❏ 1 oz. Thin Pro™CA (GPMR6002)
❏ 1 oz. Medium Pro CA (GPMR6008)
❏ 6-Minute Pro Epoxy (GPMR6045)
❏ 30-Minute Pro Epoxy (GPMR6047)
❏ Thread locking compound (GPMR6060)
❏ Balsa filler (HCAR3401)
❏ Plan protector (GPMR6167)
❏ Isopropyl rubbing alcohol (70%)
❏ Paper towels

❏ Sanding block and sandpaper (coarse, medium, fine)
❏ Hobby knife (HCAR0105)
❏ #11 blades (HCAR0211)
❏ Single-edge razor blades (HCAR0212)
❏ Razor saw
❏ Razor plane (MASR1510)
❏ Electr ic drill
❏ Dr ill bits - 1/16", 3/32", 7/64", 1/8", 5/32", 11/64", 3/16"
❏ Small Phillips and flat blade screwdrivers
❏ Pliers with wire cutter (HCAR0630)
❏ Sealing iron (TOPR2100)
❏ Heat gun (TOPR2000)
❏ T-Pins (HCAR5150)
❏ Straightedge with scale (HCAR0475)
❏ Cutting mat (HCAR0456)
❏ Builder’s triangle (HCAR0480)

❏ 10-24 Tap and Drill set
❏ Masking tape (TOPR8018)
❏ Panel line pen (TOPQ2510)

❏ CG Machine™(GPMR2400)
❏ Accu Throw™Deflection Meter (GPMR2405)
❏ CA Applicator tips (HCAR3780)
❏ CA Debonder (GPMR6039)
❏ Clevis installation tool (GPMR8030)
❏ Hot Sock™(TOPR2175)
❏ Cur ved-tip canopy scissors (HCAR0667)
❏ Top Flite Precision Magnetic Prop Balancer™(TOPQ5700)
❏ Slot Machine™motorized hinge slotting tool (GPMR4010)
❏ Precision hinge mar king tool (GPMR4005)
❏ Groove tube (GPMR8140)

Great Planes Easy-Touch Bar Sanders are made from
lightweight extruded aluminum and can be found at most
hobby shops.They are available in five sizes.

5-1/2” (GPMR6169) for those tight, hard-to-reach spots;
11” (GPMR6170) for most general purpose sanding;
22” (GPMR6172), 33” (GPMR6174) and 44” (GPMR6176)
for long surfaces such as wing leading edges. The Easy-
Touch Adhesive-Backed Sandpaper comes in 2” x 12’
rolls of 80-grit (GPMR6180), 150-grit (GPMR6183) and
220-grit (GPMR6185) and an assortment of 5-1/2” long
strips (GPMR6189) for the short bar sander.The adhesive­backed sandpaper is easy to apply and remove from your
sanding bar when it’s time for replacement.

Custom sanding blocks can be made from balsa or
hardwood blocks and dowels for sanding difficult-to­reach spots.

On our workbench, we have three 11” Great Planes
Easy-Touch™Bar Sanders, equipped with #80, #150
and #220-grit sandpaper.This setup is all that is required
for almost any sanding task. We also keep some
#320-grit wet-or-dry sandpaper handy for finish sanding
before covering.

Optional Supplies and Tools

Tools

Building Supplies

5

Elev = Elevator Fuse = Fuselage

LE = Leading Edge (front) LG = Landing Gear

Lt = Left Ply = Plywood

Rt = Right Stab = Stabilizer

TE = Trailing Edge (rear) " = Inches

1. Unroll the plan sheets, then reroll the plan inside-out to
make them lie flat.

2. Sort through the sticks and sheets, grouping them by
size. Masking tape can be used to bundle matching sheets
and sticks. Using a felt tip or ballpoint pen, lightly write the
part name or size on each piece or bundle. Refer to the
parts list and plan for sizes and quantities. Use the die-cut
patterns shown on page 7 to identify the die-cut parts and
mark them before removing them from the die sheet. Save
all leftovers.If any of the die-cut parts are difficult to remove,
do not force them! Instead, cut around the parts with a
hobby knife or lightly sand the back of the sheet. After
removing the die-cut parts, use your sanding block to lightly
sand the edges to remove any die-cutting irregularities.

3. As you identify and mark the parts, separate them into
groups, such as fuse (fuselage), wing, fin, stab (stabilizer)
and hardware.

4. Work on a flat surface. Cover the plan with wax paper or
Great Planes Plan Protector to prevent glue from sticking to
the plan.

5.When instructed to test fit parts, this means DO NOT USE

GLUE until you are satisfied that everything fits properly —
THEN glue the par ts together if instr ucted to do so.

6. Whenever the instructions tell you to glue pieces
together, use CA.When a specific type of glue is required,
the instructions will state the type of glue that is highly
recommended. When 30-minute epoxy is specified, it is
highly recommended that you use only 30-minute (or
slower) epoxy because y ou will need either the working time
and/or the additional strength.

7. The easiest way to cut balsa sticks is with a single-edge
razor blade or razor saw. Position the stick over the plan,
mark its size, then cut the part on a piece of leftover wood.
A modeling miter box works well for cutting square corners
and 45-degree gussets.

Zipper-top food storage bags are handy to store the small
parts as you sort, identify and separate them into
sub-assemblies.

IMPORTANT BUILDING NOTES

1/64" = .4mm
1/32" = .8mm
1/16" = 1.6mm
3/32" = 2.4mm

1/8" = 3.2mm
5/32" = 4mm
3/16" = 4.8mm

1/4" = 6.4mm

3/8" = 9.5mm

1/2" = 12.7mm

5/8" = 15.9mm

3/4" = 19mm

1" = 25.4mm
2" = 50.8mm
3" = 76.2mm

6" = 152.4mm
12" = 304.8mm
15" = 381mm
18" = 457.2mm
21" = 533.4mm
24" = 609.6mm
30" = 762mm
36" = 914.4mm

1" = 25.4mm (conversion factor)

Metric Conversions

Types of Wood

Common Abbreviations

6

7

NOT USED

DIE-CUT PATTERNS

NOT

USED

NOT

USED

❏ 1. Cover the fin/rudder portion of the plan with wax paper
or Great Planes Plan Protector.

❏ 2. Pin the die-cut 3/16" balsa fin frame V-1, V-2 and V-3 in
position on the fuse plan, sanding the mating edges as required
for a good fit.Use thin CA to glue the fin frame together.

❏ 3. From one of the 3/16" x 3/8" x 30" balsa sticks, cut and
glue a fin base between V-1 and V -3 along the bottom of the fin.

❏ 4. From the 3/16" x 3/16" x 24" balsa stick, cut and glue
the fin rib to the frame.

❏ 5. Remove the fin from your building board.Inspect all the
glue joints and add CA to any joints that don’t look strong.
Fill any gaps with balsa sanding dust and a drop or two of
thin CA.

❏ 6. Build the r udder frame from the die-cut 3/16" balsa R-1
and R-2 frame pieces, a 3/16" x 3/8" x 30" balsa stick and the
small 3/16" x 3/8" x 5/8" hardwood tailgear support.

❏ 7. From the 3/16" x 3/16" x 24" balsa stick, cut and glue
the rudder ribs to the frame.

❏ 8.Remove the rudder from your building board.Inspect all
the glue joints and add CA to any joints that don’t look
strong.Sand the rudder and fin to shape using the fuse plan
as a guide. Sand both sides of the r udder and fin flat and
even.Be careful that you don’t sand any area too thin.

❏ 1. Cover the stabilizer/elevator portion of the plan with
wax paper or Great Planes Plan Protector.

❏ 2. From one of the 3/16" x 3/8" x 30" balsa sticks, cut the
stabilizer trailing edge to match the stabilizer plan. Pin the
stab TE over the plan.

❏ 3. Pin the die-cut 3/16" balsa leading edge S-1 and stab
center S-5 in position. Glue S-1 to S-5 and S-5 to the front

of the stab TE.

Build the Stabilizer & Elevator

Build the Fin & Rudder

BUILD THE T AIL SURF ACES

8

❏ 4. Pin the die-cut 3/16" balsa stab frames S-2 and S-3 in
position. Glue S-2 and S-3 to S-1 and the stab TE.

❏ 5. From the 3/16" x 3/16" x 24" balsa stick, cut and glue
the stab ribs to the stab frame.Glue the 3/16" die-cut balsa
stab gussets S-4 to the stab TE and S-5.

❏ 6. Remove the stab from your building board. Inspect,
glue and sand as you did with the fin.

❏❏7.From a 3/16" x 3/8" x 30" balsa stick, cut the elevator
leading edge to length and pin it over the elevator plan.Pin

and glue the die-cut 3/16" balsa elevator frame E-1 through
E-4 to the LE.

❏❏8.From the 3/16" x 3/16" x 24" balsa stick, cut and glue
the elevator ribs to the frame.

❏ 9. Repeat steps 7 and 8 to build the second elevator half.

❏ 10. Remove the elevators from your building board.

Inspect, glue and sand as you did with the fin.

❏ 11. Pin both elevators in position over the plan. Lay the
3/32" elevator joiner wire on top of the elevators in the
position shown on the plan. Use a pencil to lightly mar k the
outline of the joiner wire on the elevators.

❏ 12. Using a straightedge, extend the side lines of the
elevator joiner outline forward to the leading edge.Also, use
a Precision Hinge Marking Tool to draw a centerline on
the leading edge. Using these lines, you can determine
exactly where to drill the holes for the elevator joiner wire.

9

❏ 13. Drill a 3/32" hole into the leading edge of both
elevators. As you drill each hole, keep the drill aligned with
the top and bottom surface of the elevator and reference
lines you made in the previous steps.

❏ 14. Refer to the Expert Tip that follows or use a Great
Planes Groove Tube™to cut a 3/32" groove in the leading
edge of both elevators to recess the joiner wire.

❏ 15.Temporarily join the elevators with the joiner wire.The
joiner wire will be easier to install if you chamfer (bevel) the
ends a little. If necessary, “tweak” the joiner wire so the
elevators are parallel and la y flat on y our building tab le when
the joiner wire is installed. If you found it necessary to
“tweak” the joiner wire, use a felt-tip pen to mark it so you
can install the joiner wire in the same orientation when you
permanently join the elevators.

❏ 16. Lay the elevators and stab over the plan and lightly
mark the hinge locations on the LE of the elevators and the
TE of the stab. Repeat the process to mark the hinge
locations on the LE of the rudder and TE of the fin.

To cut the hinge slot, place the blades onto the wood
where you want the slot. Lightly press the teeth into the
wood.When you are satisfied with the location, press the
button on the handle and the blades will cut easily into the
balsa wood.

We have simplified the task of cutting hinge slots with the
introduction of the Great Planes Slot Machine™. This
simple electric tool cuts a perfect width slot for use with
CA hinges.

B. Use the sharpened tube to carefully gouge the leading
edge of the elevators.You’ll have to make several passes
to make the recess deep enough for the joiner wire.

A. Use a #11 knife blade to sharpen the inside of a piece
of 3/32” brass tube. Roll the tube as you carve the end.

HOW TO CUT A GROOVE FOR A JOINER WIRE

10

11

If you choose not to purchase a Slot Machine™you can
make the slots by following these instructions.

❏ 17. Cut the hinge slots in the elevators, stabilizer, fin and
rudder using a Hobby Knife with a #11 blade. Begin by
carefully cutting a very shallow slit at the hinge location to
accurately establish the hinge slot.Make three or four more
cuts, going a little deeper each time. As you cut, slide the
knife from side to side until the slot has reached the proper
depth and width for the hinge.

❏ 18. Cut the 3/8" x 1" hinges for the elevator and rudder
from the supplied 2" x 9" hinge material, then snip off the
corners. Temporarily join the elevators to the stab and the
rudder to the fin with the hinges, adjusting any hinge slots if
necessary so they all align.Do not glue in the hinges until

you are instructed to do so.

❏ 1. Refer to the Expert Tip that follows and shape the
leading edge of the elevators and rudder to a “V” as shown
on the plan.

❏ 2. Use the same procedure to bevel the leading edge of
the rudder.

❏ 3. Temporarily attach the elevators to the stab and the
rudder to the fin. Use your bar sander to round the entire
perimeter of the elevator, stab, rudder and fin (do not round
the bottom edge of the fin where it will be glued to the stab
and fuse).

Start by building the left wing panel right side up over the
left wing panel plan so your progress matches the photos.

❏ 1. Set aside two of the hardest and straightest 1/4" x 1/4"
x 13" balsa sticks for use later to make pushrods.

❏ 2.The shaped and notched balsa wing leading edges are
fastened together by a thin web of balsa.Separate the LE’s
by folding them until the balsa web breaks. Sand away the
excess balsa that remains along the edges, using a sanding
bar with 150-grit sandpaper. Before using the leading edge
you must determine which one to use for the left wing panel.
Here’s how:

A.We have drawn a red line on the top of each piece.
B.The pieces are notched on one end but not on the other.

The notched end goes toward the wing tip.
C. Position one of the leading edge pieces on the left wing

panel plan with the red line up.If the notched end is on the
left side (at the tip) you have the correct piece. (When
building the right wing panel the red line must be up, with
the notched end on the right side, at the tip).

Build the Wing Panels

BUILD THE WING

B.Using the “bevel to”lines and the centerline as a guide,
make the “V” on the leading edge of the elevators with a
razor plane or your bar sander with 150-grit sandpaper.

A. Place the leading edge of one of the elevators on your
work surface and use your pen to mark a “bevel to” line
on both sides, about 3/32” high.

Note: You will probably have to adjust the height of the
elevator with card stoc k so your “be vel to”line is not too high.

HOW TO BEVEL THE LEADING EDGES

Finish the Tail Surfaces

12

❏❏3. Cover the left wing panel plan with wax paper or
Great Planes Plan Protector.

❏❏4. Match the 3/16" x 3/16" x 26-1/4" basswood main
spars so any warps will counteract each other.

❏❏5. Pin one of the main spars in position over the plan,
aligning one end of the main spar with the outside edge of
the tip rib W-4.

❏❏6. Pin one of the die-cut 1/8" balsa trailing edges,
notches facing up, in position over the plan. The TE is
notched at one end and not the other.The notched end goes
toward the wing root (wing center).

❏❏7. Glue two of the die-cut 1/16" balsa W-4 ribs together
to make the tip rib.

❏❏8. Place the W-4 ribs onto the main spar and into the
notches in the trailing edge.

❏❏9. Carefully inser t the W-4 ribs into the notches in the
leading edge. Note: Do not be concerned if the ribs do not
line up exactly with the plan. Sometimes the humidity will
cause the plan to expand or contract.Just make sure to line
everything up with the outside edge of the last rib. The
notches will provide the proper spacing.

❏❏10. With the ribs, LE and TE flat against the building
surface, glue the W-4 ribs to the spar, LE and TE.

❏❏11. From a 1/16" x 3" x 30" balsa sheet, cut the wing
center sheeting to fit between the TE and main spar and

the LE and main spar. Make sure to leave a 1/16" slot, for
the dihedral brace, in the sheeting at the back of the main
spar.Pin the sheeting in position. Then, glue the sheeting to
the main spar, LE and TE.

13

❏❏12. Position the die-cut 3/32" balsa ribs W -2 and W-3 in
position. Important: Rib W-2 does not fit into the notch in the
LE. Rib W-2 fits into the notch in the TE and aligns with the
alignment marks on the wing plan in front of the LE. Glue
only W-3 to the LE, TE, main spar and center sheeting.

❏❏13. Position the top 3/16" basswood spar in the rib
notches with one end flush with the outside edge of the tip
rib and glue to all the ribs except W-2.

❏❏14. Position the die-cut 3/32" balsa rib W-1 in place
between the main spars, with the bottom edge flat against
the center sheeting. Use the die-cut 1/8" ply dihedral
gauge to set the rib at the proper angle (see the drawing on
the wing plan). Position the die-cut 3/32" balsa LE joiner
between ribs W-1 and W-2. When you have W-1, W-2 and
the LE joiner positioned properly, glue them in place.

❏❏15. Glue the two die-cut 1/8" ply wing strut plates in
position.The wing strut plates must be flat on the table, flush
with the bottom of the wing.

❏❏16. From the 1/16" x 3" x 30" balsa sheet, cut and glue
vertical grain shear webs to the spars in the locations
shown on the plan.It is not necessar y for the shear webs to
be glued to the ribs. Make sure they are glued securely to
the wing spars. Do not install shear webs in the rib bays

between ribs W-1 and W-3.

❏❏17.Carefully sand the top of the LE joiner flush with the
top of ribs W-1 and W-2.

❏❏18. From a 1/16" x 3" x 30" balsa sheet, cut pieces to
make the top center section sheeting (don’t forget the 1/16"
notch for the dihedral brace). When satisfied with the fit,
apply medium CA to the top of the ribs and press the
sheeting in place. Note: If the balsa sheeting supplied in
your kit is difficult to bend over the front portion of the ribs
without cracking, wet the top surface of the sheeting with
water.The water will soften the wood, making it much easier
to bend.

❏❏19. From one of the remaining 1/4" x 1/4" x 13" balsa
sticks, cut four 1" long hinge blocks.Glue the hinge blocks
in position, centered on the TE.

14

❏❏19. Remove the wing from your building board. Use a
razor saw to trim the LE and top and bottom center sheeting
flush with rib W-2 and the LE joiner. Trim and sand the top
and bottom main spars and center sheeting flush with the
side of rib W-1.Sand the TE flush with the tip rib W-4.

❏❏20. Sand the top and bottom of the LE and TE flush
with the ribs.

❏ 21. Now, go back to step 2 and build the right wing panel.
Remember! Build it over the right wing plan.

❏1. Draw a centerline on the die-cut 1/16" ply dihedral brace.
The top of the dihedral brace has a slight "V" shape.

❏ 2. Using a razor saw, carefully cut a 1/16" slot in ribs
W-1, just behind the main spar.Trial fit the dihedral brace in
the slots.

❏ 3. Sand the bottom of both wing panels near the center, to
remove any excess glue on the spars or sheeting that may
prevent the wing from resting flat on your building board.

❏ 4.Assemble the die-cut 1/8" ply wing tip jig and wing tip
jig feet.

❏ 5. Trial fit the wing halves together with one wing half flat
on your building board and the wing tip jig under the tip rib
of the other wing panel. Use a sanding bar to sand the
center joint as necessary until the wing halves fit together
without any gap.

❏ 6.When satisfied with the fit, apply 30-minute epoxy to
the dihedral brace, main spars and ribs W-1. Do not apply
epoxy within 1/4" of the wing dowel slot in W-1. You need to
avoid getting epoxy in the slot. Slide the two wing halves
together with the dihedral brace in place.With the two wing
halves aligned, use masking tape to hold the wing halves
together. Wipe off any excess epoxy with a paper towel
dampened with rubbing alcohol. Weight one of the wing
halves down flat on your building board, with the other wing
half supported by the wing jig positioned at the wing tip.
Allow the epoxy to cure before moving the wing.

Note: While waiting for the epoxy to cure, let’s continue with
assembling the wing tips.

Join the Wing Panels

❏ 1. Cover the wing tip portions of the wing plan with wax
paper or Great Planes Plan Protector.

❏❏2. Assemble the wing tip from the die-cut 1/8" balsa
parts T-1, T-2, T-3 and T-4. There are two of each part (one
for each wing tip). Position the wing tip parts over the plan
and glue them together.Fill any gaps with medium CA, then
sand smooth.

❏❏3. With one of the wing panels flat on your building
table, glue the die-cut 1/16" balsa wing tip brace W-6 to the
end of the spars and tip rib W-4. The slot in W-6 must be

facing upward.

❏❏4. Trial fit the wing tip assembly against the end of the
LE and TE. Center the LE of the wing tip on the end of the

wing LE. The TE of the wing tip should rest on the building
table.Sand off the end of W-6 until it just touches the inside
edge of the wing tip.

❏❏5. With the wing tip centered on the LE and resting on
the table at the TE, glue the wing tip to the LE, TE and W-6.

❏❏6. Trial fit the die-cut 1/16" balsa rib W-5 in the notch in
W-6.Sand the rib if necessary for a good fit and glue in place.

❏❏7. Sand the front and rear of W-5 to blend into the
rib contour.

❏❏8. From a 1/4" x 1/4" x 13" balsa stick, cut and glue
wing tip filler blocks on the top and bottom of the wing tip
LE and on the top of the wing tip TE.

❏❏9. Use a sanding bar to blend the filler blocks into the
wing tip.Round the edges of the wing tip.

❏ 10. Go back to step 2 and assemble the other wing tip.

Assemble & Install the Wing Tips

15