GREAT PLANES Tracer Instruction 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. Further, 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 buyer is not prepared to accept the liability associated with the use of this product,the buyer is advised to
return this kit immediately in new and unused condition to the place of purchase.

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

TCR4P03 V1.0© Copyright 1999

P.O.Box 788 Urbana, IL 61803 [phone]

WWW.GREATPLANES.COM

INSTRUCTION MANUAL

USA

MADE IN

Safety Precautions......................................................................2

Precautions .................................................................................2

Introduction.................................................................................3

Decisions You Must Make ..........................................................3

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

Landing Gear Configuration...................................................3

Preparations................................................................................3

Accessories Required to Complete Your Tracer.....................3

Suggested Building Supplies and Tools.................................4

Other Tools or Accessories You May Require........................4

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

Common Abbreviations Used in this Manual and on the Plans...5

Types of Wood.......................................................................5

Get Ready to Build ................................................................5

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

Build the Tail Surfaces................................................................8

Build the Stab and Elevators .................................................8

Build the Fin and Rudder.......................................................9

Hinge the Tail Surfaces........................................................10

Finish the Tail Surfaces........................................................10

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

Build the Wing Spars...........................................................11

Add the Rib Doublers...........................................................11

Build the Wing Panels..........................................................12

Join the Wing Panels...........................................................17

Retract Servo and Linkage Installation................................18

Finish the Top of the Wing ...................................................20

Hinge the Ailerons ...............................................................22

Build the Fuselage....................................................................22

Assemble the Fuselage Formers and Sides........................22

Assemble the Belly Pan.......................................................25

Mount the Wing to the Fuselage..........................................25

Install the Firewall, Pushrod Tubes and Tank Hatch ............27

Build the Fuselage Front Deck and Turtle Deck...................28

Mount the Stabilizer and Fin................................................31

Mount the Engine ................................................................32

Install the Servos and Make the Pushrods..........................33

Assemble the Cowl..............................................................35

Balance the Model Laterally ................................................36

Prepare the Model for Covering...........................................36

Finish the Model ..................................................................36

Covering Technique......................................................36

Painting.........................................................................36

Final Hookups and Checks......................................................37

Join the Control Surfaces ....................................................37

Install the Hardware.............................................................38

Attach the Canopy...............................................................38

Set the Control Throws........................................................39

Balance Y our Model.............................................................39

Pre-flight....................................................................................40

Charge the Batteries............................................................40

Balance the Propeller ..........................................................40

Find a Safe Place to Fly ......................................................40

Ground Check the Model.....................................................40

Range Check Your Radio.....................................................40

Engine Safety Precautions ..................................................41

AMA Safety Code (Excerpt) ................................................41

General.........................................................................41

Radio Control ...............................................................41

Flying .........................................................................................41

Flutter Caution.....................................................................41

Takeoff .................................................................................42

Flying...................................................................................42

Landing................................................................................42

Pattern Flying.......................................................................42

Appendix ...................................................................................43

Two View Drawing.....................................................Back Cover

Your Tracer is not a toy, but rather a sophisticated, working
model that functions very much like an actual airplane.

Because of its realistic performance, the Tracer, if not
assembled and operated correctly, could possibly cause
injury to yourself or spectators and damage property.

If this is your first low wing sport model, we recommend
that you get help from an experienced, knowledgeable
modeler with your first flights. You'll lear n 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 may also contact the national Academy of Model
Aeronautics (AMA), which has more than 2,500 chartered
clubs across the country. Contact the AMA at the address
or toll-free phone number below.

Academy of Model Aeronautics

5151 East Memorial Drive

Muncie, IN 47302-9252

Telephone. [phone]

Fax [phone]

Or via the internet at: http://www.modelaircraft.org

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 unflyable model. In a few cases the plans and
instructions may differ slightly from the photos. In those
instances the written instructions are correct.

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

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

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

5. 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.

6. If you are not already an experienced R/C pilot, you must
fly the model only with the help of a competent, well
experienced R/C pilot.

PRECAUTIONS

SAFETY PRECAUTIONS:
PROTECT Y OUR MODEL,

YOURSELF AND OTHERS

TABLE OF CONTENTS

2

Remember:Take your time and follow the instructions 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
model, please call us at [phone] or e-mail us at
[e-mail] and we'll be glad to
help. If you are calling for replacement parts, please
look up the part numbers and the kit identification
number (stamped on the end of the carton) and have
them ready when calling.

For the most up to the minute “Tech Notes” check our Web
site at www.greatplanes.com.

Congratulations and thank you for purchasing the Great
Planes Tracer. The Tracer is intended to be an easy-to­build, easy-to-fly, competition-ready first patter n plane. This
aircraft builds just like any conventional sport plane you've
ever built, handles like a 2-meter pattern aircraft, yet slows
down and lands as easily as your first low wing.

Framing the model is very straightforward, as most of the
structure features interlocking balsa and lite-ply. These fully
detailed instructions include complete instructions for
retract installation or fixed gear.

Flying the Tracer is a thrilling and pleasurable
experience–as it should be for an aerobatic model designed
specifically for pattern style flying! It doesn't take much
elevator or aileron throw to put the Tracer through its paces.
When you have a feel for your Tracer, the throws can be
increased to high rates (see page 39) to complete the
aerobatic potential.The Tracer performs surprisingly well on
an inexpensive .40 and even better on a ball bearing .46
2-stroke, but seasoned experts will want to get the most out
of the Tracer by strapping on a .70 4-stroke.

We hope you enjoy building and flying your Great Planes
Tracer as much as we did the prototypes. Even if you never
plan to compete, many modelers find the contest
sequences and trimming information included on pages
42–44 beneficial for sharpening their flying skills and
providing new challenges.

❏4-Channel Radio with Five Servos (twin aileron servos

required)

❏One Y-Harness (HCAM2500 for Futaba) or Two 12"

Servo Extensions (HCAM2100 for Futaba) and
Computerized Radio

Optional radio equipment:

❏5-Channel Radio and Retract Servo Required for

Optional Retract Installation

❏Engine – See Engine Selection (above)
❏Spare Glow Plugs (O.S. #8 for most 2-stroke engines,

OSMG2691, Type-F for most 4-stroke engines,
OSMG2629)

Items in parentheses (OSMG2691) are suggested part
numbers recognized by distributors and hobby shops
and are listed for your ordering convenience. GPMQ is
the Great Planes brand, TOP is the Top Flite

®

brand

and HCA is the Hobbico

®

brand.

Accessories Required to

Complete Y our Tracer

PREPARATIONS

Engine Selection

There are several engines that will work well in the Tracer,
but for unlimited performance we recommend a hot 2-stroke
such as an O.S.

®

.46FX or SuperTigre®G-45. If you prefer

a 4-stroke, an O.S. .52 Surpass

™

works well and the O.S.

.70 Surpass makes unlimited vertical lines a par t of every

flight experience.

Landing Gear Configuration

This plane's design provides you the option for retractable
landing gear, including complete, detailed instructions for
mechanical retracts. Even if you've never worked with
retracts before, if you purchase the items recommended
below and follow our step-by-step instructions, you should
have little difficulty.

Retractable Landing Gear (HCAP4010)
Retract Servo (Futaba

®

S136G, FUTM0670)
(2) Adjustable Axle 5/32" (GPMQ4281)
(2) Pushrod with Clevis (GPMQ3772)
(2) Screw-Lock Pushrod Connector (GPMQ3870)
(8) #4 x 1/2" Sheet Metal Screw (GPMQ3154)
1/32" x 2" x 20" Ply (For making the wheel wells)

DECISIONS YOU MUST MAKE

INTRODUCTION

NOTE: We, as the kit manufacturer, provide you with a top
quality kit and great instructions, but ultimately the quality
and flyability 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.

3

❏Propeller (Top Flite Power Point

®

); Refer to your engine's

instructions for proper size

❏Top Flite Super MonoKote

®

Covering (Approximately 2

rolls) – See Covering (page 36)

❏Fuel-Proof Paint – See Painting (page 36)
❏3' Medium Fuel Tubing (GPMQ4131)
❏1/4" Latex Foam Rubber Padding (HCAQ1000)
❏10 oz.Fuel Tank (GPMQ4104)
❏Two 2" Wheels (GPMQ4221) (2-1/2" wheels desirable

for grass fields)

❏2-1/4" White Spinner (GPMQ4515)
❏Great Planes Easy Fueler

™

Fueling System (GPMQ4160)

❏3/4" Tailwheel (GPMQ4240)

These are the building tools, glue, etc. that we recommend
and mention in the manual.

We recommended Great Planes Pro™CA and Epoxy

❏1 oz.Thick CA- (GPMR6014)
❏2 oz.Thin CA (GPMR6003)
❏2 oz.Medium CA+ (GPMR6009)
❏CA Accelerator (GPMR6035)
❏6-Minute Pro Epoxy (GPMR6045)
❏30-Minute Pro Epoxy (GPMR6047)
❏Pacer Formula 560 Canopy Glue (PAAR3300)
❏#1 Hobby Knife Handle (HCAR0105)
❏#11 Blades (HCAR0311, 100 Qty.)
❏HobbyLite Filler (HCAR3401)
❏X-Acto Razor Saw (XACR2531)
❏Hobbico Builder's Triangle Set (HCAR0480)
❏Small T-Pins (HCAR5100)
❏Medium T-Pins (HCAR5150)
❏Great Planes Plans Protector (GPMR6167)
❏Masking Tape
❏1/4-20 Tap (GPMR8105, drill bit included)
❏Great Planes Dead Center

™

Engine Mount Hole Locator

(GPMR8130)

❏Electric Power Drill
❏Drill Bits: 1/16", 5/64", 3/32", 7/64", 1/8", 5/32", #18 or

11/64", 3/16", #10 or 13/64" (unless purchased with 1/4­20 Tap listed above), 1/4", 17/64"

❏String (for aligning wing and stabilizer)
❏Screwdrivers (Phillips and Flat Blade)
❏Sealing Iron (TOPR2100)
❏CG Machine

™

(GPMR2400)

❏AccuThrow

™

Deflection Meter (GPMR2405)

❏Bar Sander or Sanding Block and Sandpaper (coarse,

medium, fine grit)

Made of durable, lightweight aluminum, Easy-Touch

™

Sanders have a uniquely contoured handle that lets you
work longer with less fatigue! The incredibly flat sanding
surface removes high spots with ease. The 5.5" Hand
Sander is ideal for small parts and tight spaces. Use the
11" - 44" Bar Sanders for larger areas.Take the

guesswork
out of sanding curved or angled shapes with the
Easy-Touch Multi-Sander. Available in 11" and 22"

lengths.
Easy-Touch adhesive-backed sandpaper is already
trimmed to these tools’ width...just cut it to length and
press in place.Available in 4 different grits.

GPMR6169 Easy-Touch Hand Sander-5.5"
GPMR6170 Easy-Touch Bar Sander-11"
GPMR6172 Easy-Touch Bar Sander-22"
GPMR6174 Easy-Touch Bar Sander-33"
GPMR6176 Easy-Touch Bar Sander-44"
GPMR6190 Easy Touch Multi-Sander-11"
GPMR6191 Easy Touch Multi-Sander-22"
GPMR6180 Easy-Touch 80-Grit Sandpaper-12' roll
GPMR6183 Easy-Touch 150-Grit Sandpaper-12' roll
GPMR6184 Easy-Touch 180-Grit Sandpaper-12' roll
GPMR6185 Easy-Touch 220-Grit Sandpaper-12' roll

❏CA Applicator Tips (HCAR3780)
❏Epoxy Brushes (GPMR8060)
❏Epoxy Mixing Sticks (GPMR8055, Qty. 50)
❏CA Debonder (GPMR6039)
❏Clevis Installation Tool (GPMR8030)
❏Hot Sock (TOPR2175)
❏Trim Seal Tool (TOPR2200)
❏Heat Gun (TOPR2000)
❏Single Edge Razor Blades (HCAR0312, 100 Qty.)
❏Razor Plane (MASR1510)
❏36" Non-Slip Straightedge (HCAR0475)
❏Denatured or Isopropyl Alcohol (for epoxy clean-up)
❏Dremel

®

Moto-Tool®or Similar w/Sanding Drum, Cutting

Burr, Cut-off Wheel

❏Curved-Tip Canopy Scissors (HCAR0667)
❏Servo Horn Drill (HCAR0698)

Part Numbers for Other Tools or

Accessories Y ou May Require

Suggested Building

Supplies and Tools

4

5

There are two types of screws used in this kit:
Sheet metal screws are designated by a number and a

length. For example #4 x 5/8"

Machine screws are designated by a number, threads per
inch and a length. For example 2-56 x 5/8"

When you see the term “test fit” in the instr uctions, it
means you should first position the part on the assembly
without using any glue, then slightly modify or “custom fit”
the part as necessar y for the best fit. Do not glue until told
to do so.

When you see the term “fit” in the instr uctions, it means
you should first position the part on the assembly without
using any glue, then modify or “custom fit” the par t as
necessary for the best fit. Glue when you are satisfied with
the fit.

Where you see the term “glue”, it is at your option to select
the thickness of CA with which you are most comfortable. If
the step indicates a particular thickness of glue, be sure to
use the thickness recommended for strength, penetration
and/or working time.

Whenever just “epoxy” is specified you may use either 30-
minute epoxy or 6-minute epoxy. When 30-minute epoxy is
specified it is highly recommended that you use only 30­minute epoxy because you will need the working time
and/or the additional strength.

Several times during construction we refer to the “top” or
“bottom” of the model or a part of the model. For example,
during wing construction we may tell you to “glue the top
main spar” or “trim the bottom of the former.” It is
understood that the “top” or “bottom” of the model is as it
would be when the airplane is right-side-up and will be
referred to as the “top”even if the model is being worked on
upside-down. I.E. the “top” main spar is always the “top”
main spar even when the wing is oriented upside-down.

Fuse = Fuselage
Stab = Horizontal stabilizer
Fin = Vertical fin
LE = Leading edge (front)
TE = Trailing edge (rear)
LG = Landing gear
Ply = Plywood
Bass = Basswood
" = Inches

Balsa Basswood Plywood

❏ 1. Unroll the plan sheets. Re-roll the plans inside out to

make them lie flat.

❏ 2. Remove all parts from the box. As you do, figure out

the name of each part by comparing it with the plans and
the parts list included with this kit. Using a felt tip or ball
point pen, lightly write the part name or size on each piece
to avoid confusion later. Use the die-cut patter ns shown on
pages 6 and 7 to identify the die-cut parts and mark them
before removing them from the sheet. Save all leftovers. If
any of the die-cut parts are difficult to punch out, do not
force them! Instead, cut around the parts with a hobby
knife. After punching out the die-cut parts, use your Bar
Sander or sanding block to lightly sand the edges to
remove any die-cutting irregularities or slivers.

❏3.As you identify and mark the parts, 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 sub­assemblies.

Get Ready to Build

Types of Wood

Common Abbreviations Used in this

Manual and on the Plans

Building Notes

6

DIE-CUT PATTERNS

0" 1" 2" 3" 4" 5" 6" 7"

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180

Inch Scale

Metric Scale

7

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

METRIC CONVERSIONS

You may remove the stabilizer and elevator drawing from
the plan by cutting along the dashed line. Don't forget to
cover the plan with Great Planes Plan Protector so the glue
won't stick to the plan.

While the placement of the outer framing of any stick-built
part is impor tant, the exact placement of the internal ribs
is not so critical. It is more important to have the ribs fit
properly between the framework and have strong, secure
glue joints than to have them placed in an exact location.
If you need to slide an internal rib left or right as much as
1/8" within the Tracer's tail framework to gain a snug fit
and a strong glue joint, feel free to do so.

❏ 1. Remove the two die-cut 3/32" balsa stab centers and

the two die-cut 3/32" balsa stab LE supports from the die
sheet as shown in the sketch.

❏ 2. Laminate the stab centers and the LE suppor ts

together with medium CA, making a 3/16" stab center and
a 3/16" LE support.

❏ 3. Pin the laminated 3/16" balsa stab LE suppor t in

position over the plan. Fit and glue the laminated 3/16"
balsa stab center to the LE support.

❏ 4. Using two 3/16" x 1/2" x 24" balsa sticks, cut, fit and

glue the stab TE support and stab TE in place. NOTE: Be
sure to cut the angle on the ends of the TE support as
shown on the plans.

❏ 5. From a 3/16" x 1/2" x 24" balsa stick, cut, fit and glue

the stab LE and remaining outer framework.

❏ 6. From a 3/16" x 1/4" x 12" balsa stick, cut, fit and glue

the stab ribs in place.

❏ 7. Unpin the stab from the plan. Inspect all glue joints

and re-glue with CA as necessary. Use a bar sander or a
large sanding block and 220-grit sandpaper to sand the
entire top and bottom surface of the stab framework until it
is flat and even.Be careful while sanding so that you do not
over-thin any one particular area of the stab or gouge the
stab ribs by snagging the sandpaper on them.

Note: Refrain from using excessive accelerator. Even
hours after it’s sprayed on, residual accelerator can
prematurely and unexpectedly cure the CA you use later
on nearby glue joints. Unless you must handle or remove
the part from the building board right away, we
recommend using no accelerator at all.

Build the Stab and Elevators

BUILD THE T AIL SURFACES

8

LE Support

Stab Center

Remove the Stab Center

and the LE Support from

the Balsa die sheet.

❏❏8. Edge glue two 1/16" x 3" x 24" balsa sheets

together, making a 1/16" x 6" x 24" balsa sheet. Sand both
sides of this sheet smooth.

❏❏9. Glue the stab framework to the sheeting, aligning

the TE and the left outer edge of the framework with the
edges of the sheeting. Tr im the sheeting around the stab
framework. NOTE: It is impor tant to glue the sheeting
securely to the stab center.

❏ 10. Repeat steps 8 and 9, sheeting the other side of the

stab, again being sure to glue it securely to the stab center.

❏11.Sand the flat on the LE of the stab as shown on the plan.

❏ 12. From the 1-3/4" x 24" tapered balsa elevator stock,

cut two elevator halves to the shape shown on the plans.

❏ 1. Remove the stab plan from your work surface and lay

out the fuselage plan. Don't forget to cover the fin and
rudder areas of the plan with Great Planes Plans Protector
so the glue won't stick to the plan.

❏ 2. Using two 1/4" x 1/2" x 24" balsa sticks, cut, fit and

glue the fin framework and ribs. Don't forget the gusset at
the top of the fin. Note: The fin tail post goes all the way
down to the bottom of the fuse.

❏3. Unpin the fin from the plans. Inspect all glue joints and

reglue with CA as necessary. Sand the left and right sides
until they are flat and even.

❏ 4. Using a 1/4" x 1/2" x 24" balsa stick, cut, fit and glue

the rudder framework and ribs. It may be necessary to use
the leftover 1/4" x 1/2" balsa from the fin. Don't forget the
control horn support and the corner gussets.

❏ 5. From a 1/8" x 1/4" x 12" balsa stick, cut, fit and glue

the three cross braces in place.

❏6. Unpin the rudder from the plans. Inspect all glue joints

and reglue with CA as necessary. Sand the left and r ight
sides until they are flat and even.

Build the Fin and Rudder

9

❏ 1. Place the stab over its location on the plan and lightly

mark the hinge locations on the trailing edge with a ball
point pen. Mark the hinge locations on the elevators in the
same manner.

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.

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.Go to step 3 to complete hinging your stab.

If you choose not to purchase a Slot Machine you can
make the slots by completing step 2 below:

❏ 2. Cut the hinge slots in the elevator and stabilizer using

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.

❏ 3. Cut 3/4" x 1" hinges for the elevators and rudder from

the supplied 2" x 9" hinge material, then snip off the
corners. Temporarily join the elevators to the stab 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.

❏ 4. Return to steps 1 and 2 and complete the same

procedure to hinge the rudder and fin.

❏1. Shape the leading edge of the elevators and rudder to

a “V”as shown on the plans.

❏ 2. Use a bar sander and 150-grit sandpaper to round the

tail surfaces as shown on the plan.Note: The LE of the stab
is sanded to a sharper angle than the fin is to help tracking.

That's about it for the tail surfaces. They're a little more
work than sheet surfaces but they are much lighter, just as
strong and a nice piece of craftsmanship. Clean off the
work surface and get ready for the wing!

Finish the Tail Surfaces

Hinge the Tail Surfaces

10

1"
1"

3/4"

CUT HINGE SLOT
WITH HOBBY KNIFE
AND #11 BLADE

❏ 1. From two 1/8" x 3/8" x 30" basswood sticks, cut four

14-1/2" long spar doublers.

Before using the basswood spar doublers and spars,
examine them carefully for possible imperfections. Look
for knots, soft spots, diagonal grain and any other
imperfections. If possible, position each spar doubler so
the imperfections (if any) are on the outer half of the wing
panel (toward the tip), where they will be least affected by
high stress. If the spar doublers are warped slightly, try to
“balance them out” by installing the warped spar doublers
in opposite directions (see sketch).

❏ 2. Sand a 1-1/2" taper on one end of each spar doubler

as shown.

❏ 3. Glue the spar doublers to the four 1/8" x 3/8" x 30"

basswood spars, aligning the untapered end of the spar
doubler flush with the inboard end of the spar. From this
point forward we will refer to this combination as a spar.

❏ 4. Position 2 spars on top of each other with the spar

doublers against one another. Position the other 2 spars
similarly. Sand the inboard end of all four spars to match
the centerline of the wing, labeling each one as you do so.

Note: Make sure you make a bottom left, bottom right,
top left and top right spar. The top spars shown in the

photo have been turned upside-down and the label is
written on the bottom of the spar doubler.

Note: From this point forward, steps which are for
retractable gear installation will be in gray boxes. This will
help clarify which steps are for fixed gear and which are for
retracts. Fixed-gear-only steps will begin “If you will be
installing fixed gear”again for clarification.

RETRACT INSTALLATION

❏ 1a. If you will be building your Tracer with retracts, glue

the four die-cut 1/8 ply rib doublers with two slots to the
pair of die-cut 3/32" balsa ribs 3 and 4, being careful to
make a left and a right rib 3 and 4 as shown in the photo.
Note: Make sure the slots in the rib 3 doublers are the
same direction as the servo tray slots in the ribs 3.

Add the Rib Doublers

Build the Wing Spars

BUILD THE WING

11

❏ 1b. If you will be installing fixed gear, glue the four die-

cut 1/8" ply rib doublers with one slot to the pair of die-cut
3/32" balsa ribs 3 and 4, being careful to make a left and
right rib 3 and 4. Note: Make sure the slot in the doubler
going on rib 3 is in the same direction of the servo tray slot
in rib 3.

❏ 2. Trim the balsa ribs as shown, using the openings in

the rib doublers as a guide. Note: The ribs in the photo are
for retracts. If you are using fixed gear, trim your ribs in the
same manner but with only one landing gear rail cutout.

❏❏1. Tape the right wing plan to the work surface and

cover the wing drawing with GP Plan Protector (so you
won't glue the wing to the plan!) Remember, we are
building the right wing over the right wing bottom view.

❏❏2. Pin a 3/16" x 3/16" x 30" balsa wing jig stick over

the wing jig position shown on the plan. Note: Do not pin at
the rib positions.

❏❏3. Align the spar labeled “right top” at the inboard end

with the lettering facing up and cross-pin it in place. NOTE:
Remember that the top spar is against the plans right now
because the wing is being built upside-down.

❏❏4. Fit the die-cut 3/32" balsa ribs 3 through 9 onto the

top spar.Note: Make sure the ply rib doublers on ribs 3 and
4 face each other and the notches are up.The ribs must be
resting on the 3/16" x 3/16" wing jig.

❏❏5. Using a square to keep all the ribs perpendicular to

the work surface, glue the ribs to the top spar.

❏❏6. Use the die-cut 1/8" ply dihedral gauge to locate

the inboard end of the bottom spar, then position the
bottom spar in the ribs. Being careful not to twist the ribs,
glue the bottom spar in place.

IMPORTANT NOTE: The following instructions explain
how to build the wing directly over the plans.We'll start by
building the right wing panel upside-down over the right
wing panel plan so your progress matches the photos.

Build the Wing Panels

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❏❏7. Using a square to keep it perpendicular to the work

surface, glue the die-cut 3/32" balsa rib 2A to the spars.

❏❏8. Glue the die-cut 1/8" ply servo mount and the die-

cut 1/8" ply servo mount support in place.

❏❏9. From a 1/16" x 3" x 24" balsa sheet, cut, fit and glue

the five shear webs in place. Note:You may have to move a T­pin or two to glue the webs in place.Just replace them behind
the shear webs after the shear webs are glued in place.

❏❏10. Position the die-cut 3/32" balsa rib 2B

perpendicular to the work surface and glue it to the spars.

❏ 11. If you are building the right wing panel, trim the two

shaped balsa LE's as shown in the sketch.

❏❏12. Glue the shaped LE centered ver tically on the

front of the ribs. Trim the ends of the shaped LE flush with
the inboard side of rib 2A and flush with the outboard side
of rib 9.

❏❏13. Use the dihedral gauge to position the 3/8" x 3/8"

x 30" balsa TE at the center line of the TE of the ribs. Glue
the TE to the ribs.

If you are using fixed gear, go to step 21.

RETRACT INSTALLATION

❏❏14. Epoxy the two 1/4" x 3/8" x 4" basswood retract

rails to ribs 3 and 4.

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Center the LE on the Ribs

❏ 15. Using a rotary tool and a cutoff wheel, cut both

retract struts so they are 4-1/8" long, measuring from the
mounting plate on the retract body.

❏ 16. Place your retract in place on the rails. Drill four

5/64" pilot holes through the bass rails, using the
mounting holes as a guide. Mount the retract with four #4
x 1/2" sheet metal screws (not provided).

❏ 17. Remove the area of the rear landing gear rail that

makes contact with the coil of the retract. Do the same
where the strut makes contact with rib 3. Hint: Your rotary
tool works well for both these tasks.Just be careful not to
accidentally over trim.

❏18.If you are building your right wing panel, mount a 2"

wheel (GPMQ4221) to each of the two adjustable axles

(GPMQ4281) with 5/32" wheel collars and 6-32 set
screws. Using a rotary tool and a cutoff wheel, cut the
axles flush with the wheel collars.

❏❏19. Mount the axle on the end of the strut, centering

the wheel between the ribs. Bend the strut forward or aft as
required to center the wheel between the LE and the spar.

❏❏20 Remove the retract from the rails. Harden the

threads in the gear rails with thin CA.Go to step 22.

❏❏21. If you are using fixed gear, epoxy the grooved

basswood landing gear rail to ribs 3 and 4.

❏❏22. Edge glue a 1/16" x 3" x 30" balsa sheet to the

shaped LE, letting it contact the front edge of each rib.

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❏❏23. Being careful not to cut into the spar, use a

straightedge as a guide and cut the sheeting along the
center of the spar.

❏❏24. Being careful to keep the spar against the

building surface and the ribs on the wing jig, use medium or
thick CA to glue the sheeting to the ribs and the front half of
the spar.

❏ 25. Cut four 1/16" x 3/4" x 30" TE sheets from a 1/16"

x 3" x 30" balsa sheet.

❏❏26. Sand the TE so that it is flush with the ribs.Glue a

TE sheet to the TE and the ribs, aligning it along the TE of
the 3/8" TE stick.

❏❏27. Unpin and lift the wing from the work surface.

❏❏28. Tr im the TE sheet, TE, LE, LE sheet and the

spars flush with rib 9.

❏❏29.Trim the jig tab from rib 2A.
❏❏30. If you are using fixed gear, go to step 38.

RETRACT INSTALLATION

❏❏31. Set the wing right-side-up on your work surface.

Working a little at a time, cut an opening in the LE sheet
between the rails to fit the retract body. Mount the retract
body, then gradually cut away the sheeting for the strut
and the wheel.

❏❏32. Select or cut a piece of 1/32" x 2" x 8-3/4" ply (not

included) with the grain running the short way. Wrap it
around a soda can of your choice, allow the sheet to overlap
and glue the sheet to itself.This will be the wheel well.

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