Great Planes GPMA0155 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.

TYL2P03 for GPMA0155 V1.1 Entire Contents © Copyright 2009

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

[e-mail]

INSTRUCTION MANUAL

USA

M

A

D

E

IN

Printed In USA

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

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

PRECAUTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

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

Engine Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

PREPARATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Required Accessories . . . . . . . . . . . . . . . . . . . . . . . 3

Building Supplies. . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Optional Supplies And Tools. . . . . . . . . . . . . . . . . . . 4

Common Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4

Types Of Wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Metric Ruler. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Important Building Notes . . . . . . . . . . . . . . . . . . . . . 5

Die Patterns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

BUILD THE TAIL SURFACES. . . . . . . . . . . . . . . . . . . . . 7

Build The Fin And Rudder . . . . . . . . . . . . . . . . . . . . 7

Build The Stabilizer And Elevators . . . . . . . . . . . . . . 7

Finish The Tail Surfaces . . . . . . . . . . . . . . . . . . . . . 10

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

Build The Wing Panels. . . . . . . . . . . . . . . . . . . . . . 11

Join The Wing Panels . . . . . . . . . . . . . . . . . . . . . . 14

Assemble The Ailerons . . . . . . . . . . . . . . . . . . . . . 18

Assemble And Install The Wing Tips. . . . . . . . . . . . 20

BUILD THE FUSELAGE. . . . . . . . . . . . . . . . . . . . . . . . 20

Assemble The Fuselage Sides. . . . . . . . . . . . . . . . 20

Join The Fuselage Sides . . . . . . . . . . . . . . . . . . . . 23

Install The Engine . . . . . . . . . . . . . . . . . . . . . . . . . 27

Sheet The Front Deck . . . . . . . . . . . . . . . . . . . . . . 27

Sand The Fuselage . . . . . . . . . . . . . . . . . . . . . . . . 28

Mount The Wing To The Fuselage . . . . . . . . . . . . . 29

Mount The Stabilizer And Fin. . . . . . . . . . . . . . . . . 29

Install The Dowel Stringers. . . . . . . . . . . . . . . . . . . 31

Mount The Landing Gear . . . . . . . . . . . . . . . . . . . . 33

Assemble The Wheel Pants . . . . . . . . . . . . . . . . . . 33

Assemble The Cowl . . . . . . . . . . . . . . . . . . . . . . . . 35

Construct The Wing Struts . . . . . . . . . . . . . . . . . . . 37

RADIO INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . 38

Mount The Servos . . . . . . . . . . . . . . . . . . . . . . . . . 38

Install The Throttle Pushrod . . . . . . . . . . . . . . . . . . 40

Install The Aileron Pushrods. . . . . . . . . . . . . . . . . . 40

BALANCE THE AIRPLANE LATERALLY. . . . . . . . . . . 41

FINISHING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Final Sanding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Cover The Model With MonoKote

®

Film . . . . . . . . . 41

Painting Your Model . . . . . . . . . . . . . . . . . . . . . . . . 42

FINAL HOOKUPS AND CHECKS . . . . . . . . . . . . . . . . 42

Install The Hinges . . . . . . . . . . . . . . . . . . . . . . . . . 42

Install The Wheels . . . . . . . . . . . . . . . . . . . . . . . . . 43

Finish The Model. . . . . . . . . . . . . . . . . . . . . . . . . . 43

Reinstall The Radio System. . . . . . . . . . . . . . . . . . 44

BALANCE YOUR MODEL . . . . . . . . . . . . . . . . . . . . . . 44

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

Engine Safety Precautions. . . . . . . . . . . . . . . . . . . 46

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

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

Radio Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

FLYING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

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

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

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

2-VIEW DRAWING . . . . . . . . . . . . . . . . . . . . Back Cover

Your T-Craft 20 is not a toy, but rather a sophisticated,
working model that functions very much like an actual
airplane. Because of its realistic performance, the T-Craft
20, 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 fir st
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

Since its introduction in the late 1930's, there have been 100's
if not 1000's of the full size T-Craft sold in the U .S.A.They have
come in many versions. Some are very stable, while others
are very aerobatic, like the clipped wing T-Craft. Great Planes
has taken the aerobatic qualities of the full size Clipped Wing
T-Craft and designed them into this .20 sized scale model.
This plane loops, rolls and flies knife edge but still has the
stability of a high wing airplane. So if you’re ready for an easy
building, fun to fly airplane, let's finish reading this introduction
and start building.

While the T-Craft 20 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 flown 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. On the other hand, if you have already
learned the basics of R/C flying, and you are able to safely
handle a low wing airplane, the T-Craft 20 is an excellent
choice to improve your flying skills.

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 give us a call at [phone] or e-mail
us at [e-mail] and we'll be
glad to help. If you are calling for replacement parts,
please reference the part numbers and have them ready
when calling.

1. Build the plane according to the plans and instructions. Do
not alter or modify the model, as doing so may result in an
unsafe or unflyab le model.In a few cases the instructions may
differ slightly from the photos. In those instances the plans
and written instructions should be considered as correct.

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

3.Use an R/C radio system that is in first-class condition.We
highly recommend the use of micro servos on the ailerons
and standard servos on the rudder, elevator and throttle.

4.You must proper ly install all R/C and other components so
that the model operates properly on the ground and in the air.

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

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

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 3 standard servos and 2 micro servos
❏ (2) 24” extension for aileron servos (HCAM2200)
❏ Y-Harness for aileron servos (HCAM2500)
❏ Engine - See Engine Selection above
❏ Propeller (Top Flite Power Point®); Refer to your engine's

instructions for proper size

❏ Fuelproof paint - see Painting section
❏ Medium fuel tubing 2' (GPMQ4131)
❏ 1/4" Latex foam rubber padding (HCAQ1000)
❏ 6 oz. Fuel tank (GPMQ4102)
❏ Easy Fueler™fuel filling valve (GPMQ4160)
❏ (2) 2-1/2" Wheels (GPMQ4223)
❏ (1) 1" Tail wheel (GPMQ4241)
❏ (2) 3/32" Wheel collars (GPMQ4302)
❏ (4) 5/32" Wheel collar (GPMQ4306)
❏ Pilot (Williams Bros. #18400 1/6 scale spor tsman pilot

used in prototype)

❏ (2) Rolls covering film
❏ Aluminum spinner nut (GPMQ4630)

Required Accessories

PREPARATIONS

ENGINE SELECTION

Recommended engine size:
.25 to .32 cu. in. 2-stroke
.26 to .30 cu. in. 4-stroke

Your Great Planes T-Craft 20 will perform well with any of
the engines within the recommended range.

DECISIONS YOU MUST MAKE

PRECAUTIONS

Note: We, as the kit manufacturer , pro vide y ou with a top

quality kit and great instructions, but ultimately the quality
and flyability of your finished model depends on how y ou
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.

INTRODUCTION

3

4

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)
❏ Canopy Glue
❏ 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)
❏ Electric drill
❏ Drill bits - 1/16",3/32", 5/32", 3/16", 13/64", 7/32”, 1/4"
❏ 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)
❏ 1/4-20 Tap and Drill set (GPMR8105, drill bit included)
❏ Tap handle (GPMR8120)
❏ Masking Tape (TOPR8018)
❏ Monofilament string for aligning the wing and stabilizer
❏ Panel line pen (TOPQ2510)
❏ Groove Tube (GPMR8140)
❏ Dead Center Hole Locator (GPMR8130)
❏ Precision Hinge Marking Tool (GPMR4005)
❏ Microballoons (TOPR1090)

❏ CG Machine™(GPMR2400)
❏ Accu Throw®Deflection Meter (GPMR2405)
❏ CA Applicator tips (HCAR3780)
❏ CA Debonder (GPMR6039)
❏ Clevis installation tool (GPMR8030)
❏ Hot Sock™(TOPR2175)
❏ Curved-Tip canopy scissors (HCAR0667)
❏ Top Flite Precision Magnetic Prop Balancer™(TOPQ5700)
❏ Slot Machine™motorized hinge slotting tool (GPMR4010)

On our workbench, we have three 11" Great Planes Easy­Touch™Bar Sanders, equipped with #80, #150 and #220­grit 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.

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; and 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.

This setup is all that is required for almost any sanding task.
Custom sanding blocks can be made from balsa or hardwood
blocks and dowels for sanding difficult-to-reach spots.

Fuse = Fuselage

LE = Leading Edge (front)

TE = Trailing Edge (rear)

Stab = Stabilizer

" = Inches

Elev = Elevator

LG = Landing Gear

Ply = Plywood

Common Abbreviations

Optional Supplies and Tools

Tools

Building Supplies

1. Unroll the plan sheets, then re-roll the plans 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 plans for sizes and quantities. Use the die-cut
patterns shown on page 6 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 remov e,
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 par ts, separate them into
groups, such as fuse (fuselage), wing, fin, stab (stabilizer)
and hardware.

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

4.Work on a flat surface.Cover the plans with waxed paper
or Great Planes Plan Protector to prevent glue from stic king
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 parts together if instructed 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 you 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 cutting mat. A modeling
miter box works well for cutting square corners and 45­degree gussets.

IMPORTANT BUILDING NOTES

Types of Wood

5

Metric Conversions

1/64" = .4 mm

1/32" = .8 mm

1/16" = 1.6 mm

3/32" = 2.4 mm

1/8" = 3.2 mm
5/32" = 4.0 mm
3/16" = 4.8 mm

1/4" = 6.4 mm
3/8" = 9.5 mm
1/2" = 12.7 mm
5/8" = 15.9 mm
3/4" = 19.0 mm

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

6" = 152.4 mm
12" = 304.8 mm
18" = 457.2 mm
21" = 533.4 mm
24" = 609.6 mm
30" = 762.0 mm
36" = 914.4 mm

6

DIE-CUT PATTERNS

❏ 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 in position on
the fuse plan.

❏ 3. From one of the 3/16" x 3/8" x 30" balsa sticks, cut and
glue the fin frame together. Note that there are two pieces
along the bottom of the fin and that the TE ends at the
bottom of the stabilizer.

❏ 4. From the 1/8" x 3/16" x 30" balsa stick, cut and glue the
fin cross braces 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 rudder frame from the die-cut 3/16" balsa
R-1 and R-2 frame pieces and leftover 3/16" x 3/8" balsa stick.

❏ 7. From the leftover 1/8" x 3/16" balsa stick, cut and glue
the rudder ribs and cross brace 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.
First, sand both sides of the rudder and fin flat and even.
Then, sand the rudder and fin to shape using the fuse plan
as a guide. Be careful that you don't sand any area too thin.

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

❏ 2. From one of the 3/16" x 3/8" x 30" balsa sticks, cut the
stabilizer trailing edge and trailing edge doubler to
match the stabilizer plan.Glue the TE doubler to the TE and
pin them over the plan.

❏ 3. Pin the die-cut 3/16" balsa leading edge doubler S-1
and stab center S-2 in position. Glue S-2 to S-1 and to the
front of the stab TE doubler.

Build the Stabilizer & Elevators

Build the Fin & Rudder

BUILD THE T AIL SURF ACES

7

❏ 4. Finish constructing the stab frame from a 3/16" x 3/8" x
30" balsa stick.

❏ 5. From the 1/8" x 3/16" x 30" balsa stick, cut and glue the
stab braces to the stab frame.

❏ 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 counter balance

to the LE. Construct the remaining elevator frame from a
3/16" x 3/8" x 30" balsa stick.

❏❏8. From the 1/8" x 3/16" x 30" balsa stick, cut and glue
the elevator cross braces 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 sidelines 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.

8

❏ 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. Use the Great Planes Groove Tube to cut a 3/32"
groove in the leading edge of both elevators to recess the
joiner wire. Note: If you do not have a Groove Tube, refer to
the Following Expert Tip.

HOW TO CUT A GROOVE FOR A 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.

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

9

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

❏ 17. 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.

If you choose not to purchase a Slot Machine, refer to the
Expert Tip that follows to make hinge slots.

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 3/4" 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.Use a Precision Hinge Marking Tool to mark the
centerline on the LE of the elevator.Mark a “bevel to”line on
both sides of the elevator LE, about 3/32" from the LE.

Finish the Tail Surfaces

CUT HINGE SLOT
WITH HOBBY KNIFE
AND #11 BLADE

10

❏ 2. Using the “bev el 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.

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

❏ 4. Temporarily attach the elevators to the stab and the
rudder to the fin.Use your bar sander to round the 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 right wing panel right side up over the
right wing panel plan so your progress matches the photos.

❏ 1. Match the six 1/8" x 1/4" x 30" basswood main spars
so any warps will counteract each other.

❏ 2. Cut two of the main spars in half. Draw a line 1" from
one end of each of the 15" half spars and bevel the end of
the spars to the line.

❏ 3. Use epoxy to glue the four 15" main spars onto the four
30" main spars, as shown on the plans.Make sure the sides
and ends of the spars are flush with each other.Wipe off any
excess epoxy before it cures.

❏❏4.Cover the wing panel plan with waxed paper or Great
Planes Plan Protector.

❏❏5.Position one of the main spars over the plan, aligning
the double spar end of the main spar with the outboard edge
of the root rib W-1.Mark the spar at the tip side of ribs W-4.

Build the Wing Panels

BUILD THE WING

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❏❏6.Cut a V-notch part way through the spar , at the mark,
so that the spar can bend at W-4.

❏❏7.From one of the 1/16" x 3" x 30" balsa sheets, cut four
1/2" x 3/4" shims. Place the shims over the spar location on
the plan, starting between ribs W-2 and W-3 and alternating
every other rib bay. Pin the main spar, cut in step 6, over the
shims, aligned with the wing plan at the wing root.

❏❏8. Glue two of the die-cut 3/32" balsa W-4 ribs together
to make the W-4 outer rib.

❏❏9.Glue the die-cut 1/16" ply W-2 spar spacer to the tip
side of rib W-2, centered between the main spar notches
and the lightening holes.Tr im the main spar notches for the
1/16" plywood wing joiner.

❏❏10. Pin and glue the die-cut 3/32" balsa W-2,W-3, W-4
and W-6 ribs and the die-cut 1/8" balsa W-5 rib onto the
main spar, perpendicular to the building board.Note: There
is a W -3 and W-4 rib glued together at the root of the aileron
bay. The main spar will need to be bent upward to contact
the W-6 rib.

❏❏11.Position the 1/8" to 11/32" x 3/4" x 18" shaped balsa
trailing edge on the jig tabs of the W-2 and W-3 ribs, flush
with the outside of rib W-3.Use a straight edge to align the
top of the TE with the top of the ribs.When satisfied with the
fit, glue the TE to the ribs.Note: The TE extends 1/16" abo v e
rib W-2 to allow for the 1/16" center sheeting.

❏❏12. Fit and glue the 1/4" x 1/4" x 30" balsa sub TE in
the notches at the rear of the W -4 and W -5 ribs.Butt glue the
sub TE to rib W-6.

W4

W4

1/8" X 1/4" MAIN SPAR

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❏❏13. Hold the die-cut 1/8" plywood dihedral gauge
against the root end of the bottom main spar.With the root
end of the top main spar against the dihedral gauge, insert
and glue the spar into the notches in the top of the ribs.

❏❏14.Center the 3/32" x 5/8" x 30" balsa sub LE on the front
of the ribs.Check that the jig tabs at the aft end of the ribs are
against the building board.Then, glue the sub LE in position.

❏❏15.From the 3/16" x 3/16" x 24" basswood stic k, cut two
forward spars 6" long. Align the dihedral gauge with the
centerline of the wing. Glue the forward spars in the top and

bottom of ribs W-2 and W-3 with the root ends against the
dihedral gauge. Make sure that these forward spars are
against the back edge of the slot in W-2.

❏❏16.Cut the 3/32" x 7/8" x 24" balsa stick in half to make
the aileron bay TE. Glue one of the TE pieces, centered, on
the aft end of the W-4 through W-6 ribs and the sub TE.

❏❏17. Cut one of the 1/16" x 1/2" x 24" balsa TE sheets in
half.Test fit the TE sheet in the recess at the aft end of the
W-4 through W-6 ribs and trim as necessary.

❏❏18. From the 1/16" x 3" x 30" balsa sheet, cut and glue
vertical grain shear webs to the spars in the locations

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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.

❏❏19. Use the dihedral gauge to mark the TE at the wing
center.Trim the TE along the line.

❏❏20. Remove the wing from your building board and
install the second piece of 1/16" x 1/2" TE sheet on the
bottom of the wing. Note: The TE sheet will need to be bent
to meet rib W-6.

❏ 21. Return to step 4 and build the left wing panel.

❏ 1. Draw a centerline on the two die-cut 1/8" plywood

center wing joiners and the two die-cut 1/16" plywood
outer wing joiners.

❏ 2. Use epoxy to glue the two center wing joiners together,
aligning the centerlines and the edges.

❏ 3.Assemble the die-cut 1/8" plywood wing tip crutch and
crutch feet. Do not glue the feet to the tip crutch.

❏ 4. Trim the jig tabs off the bottom of the double W-4 ribs
on the left wing panel.Sand the bottom of the ribs, TE sheet
and aileron bay TE flush on the left wing panel.

❏ 5. Position the left wing panel on your flat building board.
Place the wing tip crutch under the double W-4 ribs. The
“TE” on the tip crutch should be toward the TE and the
crutch should be flush with the TE.

❏ 6. Insert the center wing joiners between the main spars,
the outer wing joiners on the front and back of the main wing

Join the Wing Panels

14

spars and the die-cut 1/8" plywood forward joiner in the
right wing. Slide the r ight wing half with the joiners into the
left wing half, checking the fit.The main spars, forw ard spars
and TE on both wing halv es should meet.Make sure the left
wing half is positioned on the tip crutch and the right wing
half is flat against your building board. Sight down the wing
from the wing tip, checking that the main spar, sub LE and
TE are straight. If they are not, lightly sand the ends of the
spars or TE to achieve a straight wing. Caution: Remove
only a small amount at a time.You can always remove more
wood, but cannot add more wood once it’s removed.

❏ 7. When satisfied with the fit of the wing halves, remove
the joiners. Use 30-minute epoxy to glue the two wing
halves together. Apply epoxy to the top and bottom of the
center wing joiners, the front and back sides of the main
spars, the front of the forward spars , the ends of the forward
joiner and the TE's.Slide everything back together.Wipe off
any excess epoxy with a paper towel dampened with
rubbing alcohol. Check that the tip crutch is in position, the
right wing panel is flat against your building board and the
main spar is straight. Use clamps to hold the joiners in
position until the epoxy cures.

❏ 8. Glue together the two die-cut 1/8" plywood ribs W-1A
and the two die-cut 3/32" balsa ribs W-1B.

❏ 9. Use epoxy to glue the W-1A ribs to the forward spars
and forward joiner, centered on the ply wing joiner. Glue
W-1B, centered on the ply wing joiner and the TE.

❏ 10. Glue shear webs to the aft side of the ply wing joiner
between ribs W-2 and W-3.

❏ 11. Sand the balsa sub LE flush with the top of the ribs.

❏ 12. Support one wing panel with the wing tip cr utch and

weight the other panel flat on your building board. On the
weighted panel, fit a 1/16" x 3” x 30” balsa sheet in place,
against the notch in the ribs and on top of the main spar and
over one of the W-1A ribs.Glue the balsa sheet to the main
spar and notches. When the glue has cured, apply a bead
of glue to the top of each rib, along the sub LE and forward
spar and joiner. Pull the sheeting down, making sure it
contacts the surface of each rib, sub LE and forward spar
and joiner.Hold it in place until the glue has cured.

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