Great Planes GPMA0487 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 an y 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 MANUAL BEFORE STARTING
CONSTRUCTION. IT CONTAINS IMPOR TANT

INSTRUCTIONS
AND WARNINGS CONCERNING THE ASSEMBLY AND
USE OF THIS MODEL.

P382P03 for GPMA0487 V1.0 Printed in USA Entire Contents © Copyright 2003

Champaign, IL

[phone], Ext. 5

[e-mail]

INSTRUCTION MANUAL

Wingspan: 50 in [1270mm]
Wing Area: 416 sq in [27dm

2

]

Weight: 4 – 5 lbs [1810 – 2270g]
Wing Loading: 22 – 27 oz/sq ft [68 – 85g/dm

2

]

Length: 36 – 3/4 in [933mm]
Radio: 4-channel transmitter with 6 standard ser vos
Engine: .15 – .25 cu. in. [2.5 – 4.0cc] two-stroke

™

INTRODUCTION ..........................................................................2

Scale Covering Schemes ............................................................2

SAFETY PRECAUTIONS...................................................................3

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

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

REQUIRED ITEMS ............................................................................4

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

Adhesives & Building Supplies....................................................4

Covering Tools.............................................................................4

Optional Supplies & Tools ...........................................................4

IMPORTANT BUILDING NOTES.......................................................5

COMMON ABBREVIATIONS.............................................................5

TYPES OF WOOD..............................................................................6

GET READY TO BUILD......................................................................6

METRIC CONVERSIONS...................................................................6

METRIC/INCH SCALE.......................................................................6

DIE-CUT DRAWINGS.........................................................................7

BUILD THE T AIL SURFACES............................................................8

Build the Stabilizer ......................................................................8

Build the Elevator........................................................................9

Build the Rudder .........................................................................9

BUILD THE WING.............................................................................10

Build the Wing Panels...............................................................10

Sheet the Wing Panel................................................................12

Join the Wing Panels.................................................................13

Sheet the Top of the Wing.........................................................14

BUILD THE BOOMS & FINS ...........................................................19

Assemble the Boom..................................................................19

Sheet the Boom ........................................................................20

Assemble the Engine Mounts ...................................................22

Attach the Rudder to the Fin.....................................................23

INST ALL THE ENGINES..................................................................24

MOUNT THE BOOMS ON THE WING.............................................25

Prepare the Booms & Wing.......................................................25

Install the Ailerons .....................................................................26

Build the Canopy Frame............................................................27

Fit the Canopy on the Frame ....................................................28

INSTALL THE RADIO SYSTEM.......................................................30

Install the Aileron Servos ..........................................................30

Install the Elevator & Rudder Servos........................................31

Install the Elevator Pushrod......................................................32

Connect the Rudders................................................................33

Install the Throttle Servo...........................................................34

Install the Nose Steering...........................................................35

Balance the Airplane Laterally ..................................................35

FINISHING........................................................................................36

Final Sanding ............................................................................36

Cover the Model with MonoKote

®

Film......................................36

Suggested Covering Sequence ................................................37

Painting Your Model...................................................................37

Installing & Painting the Radiators............................................37

Applying the Decals ..................................................................38

FINAL HOOKUPS AND CHECKS...................................................38

Install the Hinges.......................................................................38

Install the Landing Gear............................................................39

Install the Engines & Fuel Tanks...............................................40

Install the Canopy......................................................................40

GET THE MODEL READY TO FLY ..................................................41

Check the Control Directions ....................................................41

Set the Control Throws..............................................................41

Balance the Model (CG) ...........................................................42

PREFLIGHT......................................................................................43

Identify Y our Model....................................................................43

Charge the Batteries.................................................................43

Balance the Propellers..............................................................43

Ground Check...........................................................................43

Range Check.............................................................................43

ENGINE SAFETY PRECAUTIONS..................................................43

AMA SAFETY CODE (excerpt).......................................................44

CHECK LIST ....................................................................................44

FLYING .............................................................................................45

Engine Setup.............................................................................45

Takeoff.......................................................................................45

Flight..........................................................................................45

What To Do If One Engine Quits ...............................................45

Landing......................................................................................46

TWO VIEW DRAWING............................................Back Cover Page

FUSE & WING PLANS ................................Center Pull-Out Section

Along with the P-51, the P-38 is one of the most admired
planes of WW2. It is also one of the most difficult to build
and fly. But the Great Planes Profile 38 has eliminated those
hurdles. The booms of the Great Planes Profile 38 build
quickly and flat on your building board. The center pod is
molded from ABS, eliminating the difficult job of sheeting the
compound curves.Through extensive testing and design we
have minimized the flight problems that occur when an
engine quits in flight. So if you’re ready for an easy building,
fun to fly plane, let’s get started.

While the Profile 38 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 do not attempt to fly the Profile 38 without first
learning to fly a trainer. On the other hand, if you have
already become proficient at flying low wing airplanes, the

Profile

38 is an excellent choice for your first twin engine plane.
For the latest technical updates or manual corrections to the

Profile 38, visit the web site listed below and select the
Great Planes Profile 38.If there is new technical information
or changes to this kit a “tech notice” box will appear in the
upper left corner of the page.

http://www.greatplanes.com/airplanes/index.html

If you would like photos of the full-size P-38 to study the

photos

to add more scale details, photo packs are available from:

Bob’s Aircraft Documentation

3114 Y uk on Av e.

Costa Mesa, CA 92626

Telephone: [phone]

Fax:[phone]

E-mail:

www.bobsairdoc.com

Scale Covering Schemes

INTRODUCTION

TABLE OF CONTENTS

2

1.Your Profile 38 should not be considered a toy, but rather
a sophisticated, working model that functions very much like
a full-size airplane. Because of its performance capabilities,
the Profile 38, if not assembled and operated correctly,
could possibly cause injury to yourself or spectators and
damage to property.

2. You must assemble the model according to the
instructions. Do not alter or modify the model, as doing so
may result in an unsafe or unflyable model. In a few cases
the instructions may differ slightly from the photos.In those
instances the written instructions should be considered as
correct.

3.You must take time to build straight, true and strong.

4. You must 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.

5. You must correctly install all R/C and other components
so that the model operates correctly on the ground and in
the air.

6.You must check 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 any signs of wear or fatigue.

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

8.While this kit has been flight tested to exceed normal use,
if the plane will be used for extremely high stress flying,
such as racing, the modeler is responsible for taking steps
to reinforce the high stress points.

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

true.

Before starting to build, compare the parts in this kit
with the Parts List, and note any missing parts. Also
inspect all parts to make sure they are of acceptable

quality. If any parts are missing, broken or defective, or
if you have any questions about building or flying this
airplane, please contact Great Planes at the address or
telephone number below. If you are contacting us for
replacement parts, please be sure to provide the full kit
name (Profile 38) and the part numbers as listed in the
Parts List.

Great Planes Product Support:

3002 N Apollo Drive, Suite 1

Champaign, IL 61822

Telephone: [phone]

Fax:[phone]

E-mail:

[e-mail]

Y ou can also c heck our web site at

www.greatplanes.com

for the latest Profile 38 updates.

If you have not flown this type of model before, we
recommend that you get the assistance of an experienced
pilot in your R/C club for your first flights. If you’re not a
member of a club, your local hobby shop has information
about clubs in your area whose membership includes
experienced pilots.

In addition to joining an R/C club, we strongly recommend
you join the AMA (Academy of Model Aeronautics). AMA
membership is required to fly at AMA sanctioned clubs.
There are over 2,500 AMA chartered clubs across the
country. Among other benefits, the AMA provides insurance
to its members who fly at sanctioned sites and events.
Additionally, training programs and instructors are available
at AMA club sites to help you get started the right way.

Contact

the AMA at the address or toll-free phone number below:

Recommended Engine Size: .15 to .25 cu. in. 2-stroke

Two .15 size engines will fly the Profile 38 well. However,
if one engine quits in the air, the plane will not have
enough power to maintain level flight.The plane will have
to land. With two .25 size engines, if one engine quits in
the air, the plane can continue flying on one engine.

Engine Selection

DECISIONS YOU MUST MAKE

Academy of Model Aeronautics

5151 East Memorial Drive

Muncie, IN 47302

Tele: [phone]

Fax [phone]

Or via the Internet at:

http://www.modelaircraft.org

We, as the kit manufacturer, provide you with a top
quality, thoroughly tested kit and 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.

PRO TECT YOUR MODEL,YOURSELF

& OTHERS...FOLLOW THESE

IMPORTANT SAFETY PRECAUTIONS

3

❏ Engine and suitable propellers
❏ 4-Channel radio with 6 standard servos
❏ (2) 12" [300mm] Servo extension (HCAM2711 for

Futaba

®

)

❏ (2) Y-harnesses (HCAM2751 for Futaba)
❏ 1/4" [6mm] R/C foam rubber (HCAQ1000)
❏ (2) 4 oz. [120cc] Fuel tank (GPMQ4101)
❏ 3' [900mm] Standard silicone fuel tubing (GPMQ4131)
❏ #64 Rubber bands (1/4 lb [113g] box, HCAQ2020)
❏ (1) 2" [51mm] Nose wheel (GPMQ4221)
❏ (2) 2-1/2" [64mm] Main wheels (GPMQ4223)
❏ (2) 2" [51mm] White spinner (GPMQ4510)
❏ (2) Rolls covering film (if covering in one color), box

cover model was covered with:

Aluminum (TOPQ0205)

Black (TOPQ0208)

White (TOPQ0204)
Cub Yellow (TOPQ0220)
Olive Drab (TOPQ0210)

In addition to common household tools (screwdrivers, drill,
etc.), this is the “short list” of the most important items
required to build the Profile 38.

We recommend Great

Planes Pro™CA and Epoxy glue.

❏ 1 oz. [30g] Thin Pro CA (GPMR6002)
❏ 1 oz. [30g] Medium Pro CA+ (GPMR6008)
❏ Pro 30-minute epoxy (GPMR6047)
❏ Pro 6-minute epoxy (GPMR6045)
❏ HobbyLite

™

balsa-colored balsa filler (HCAR3401)

❏ Plan Protector

™

(GPMR6167) or wax paper

❏ Drill bits:1/16" [1.6mm], 3/32" [2.4mm], 7/64" [2.8mm],

1/8" [3.2mm], 5/32" [4mm], 3/16" [4.8mm],

❏ Small metal file
❏ Stick-on segmented lead weights (GPMQ4485)
❏ Silver solder w/flux (GPMR8070)
❏ #1 Hobby knife (HCAR0105)
❏ #11 Blades (100-pack, HCAR0311)
❏ Single-edge razor blades (10-pack, HCAR0212)
❏ Small T-pins (100, HCAR5100)
❏ Medium T-pins (100, HCAR5150)
❏ Sanding tools and sandpaper assortment (see

Expert

Tip–Easy-Touch™Bar Sander

section on page 5)

❏ Top Flite

®

MonoKote®sealing iron (TOPR2100)

or

❏ 21st Century

®

sealing iron (COVR2700)

❏

Top Flite Hot Sock™iron cover (TOPR2175)

or

❏

21st Century iron cover (COVR2702)

❏

Top Flite MonoKote trim seal iron (TOPR2200)

or

❏

21st Century trim seal iron (COVR2750)

❏

Top Flite MonoKote heat gun (TOPR2000)

Here is a list of optional tools mentioned in the manual that
will help you build the Profile 38.

❏

Pro Aliphatic resin (2 oz. [60g], GPMR6160)

❏

2 oz. [57g] Spray CA activator (GPMR6035)

❏

4 oz. [113g] Aerosol CA activator (GPMR634)

❏

CA applicator tips (HCAR3780)

❏

CA debonder (GPMR6039)

❏

Kyosho®masking film (KYOR1040)

❏

Epoxy brushes (6, GPMR8060)

❏

Mixing sticks (50, GPMR8055)

❏

Mixing cups (GPMR8056)

❏

Razor plane (MASR1510)

❏

Builder’s triangle set (HCAR0480)

❏ Metal template set (30°/60°/90° and 45° triangles,

HCAR0500)

❏

Scale warbird template (TOPQ2187)

❏

36" Metal ruler (HCAR0475)

❏ Curved-tip canopy scissors (for trimming plastic parts,

(HCAR0667)

❏

Pliers with wire cutter (HCAR0630)

❏

Robart Super Stand II (ROBP1402)

❏

18" x 24" [460 x 610mm] Builder’s cutting mat
(HCAR0455)

❏

16" x 48" [410 x 1220mm] Building board (GPMR6950)

❏

Hobbico®Duster™can of compressed air (HCAR5500)

❏

Masking tape (TOPR8018)

❏

Threadlocker™thread locking cement (GPMR6060)

❏

Denatured alcohol (for epoxy clean up)

❏

Panel Line Pen (TOPQ2510)

❏

Z-bend pliers (HCAR2000)

❏

Rotary tool such as Dremel®Moto-Tool

®

❏

Rotary tool reinforced cut-off wheel (GPMR8200)

❏

Servo horn drill (HCAR0698)

❏

Hobby Heat™micro torch (HCAR0750)

❏

Dead Center™Engine Mount Hole Locator (GPMR8130)

❏

AccuThrow™Deflection Gauge (GPMR2405)

❏

Slot Machine™ hinge slotting tool (110V, GPMR4010)

❏

CG Machine™(GPMR2400)

❏

Laser incidence meter (GPMR4020)

❏

Precision Magnetic Prop Balancer™(TOPQ5700)

Optional Supplies & Tools

Covering T ools

Adhesives & Building Supplies

Required Accessories

REQUIRED ITEMS

4

• There are two types of screws used in this kit:

Sheet metal screws are designated by a number and a
length.

For example #6 x 3/4"

This is a number six screw that is 3/4" long.

Machine screws are designated by a number, threads per
inch, and a length.SHCS is just an abbreviation for “sock et

head

cap screw” and that is a machine screw with a socket head.

For example 4-40 x 3/4".

This is a number four screw that is 3/4" long with forty
threads per inch.

• When you see the term

test fit

in the instructions, it
means that 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.

• Whenever the term

glue

is written you should rely upon
your experience to decide what type of glue to use.When a
specific type of adhesive works best for that step, the
instructions will make a recommendation.

• Whenever just

epoxy

is specified you may use

either

30-minute (or 45-minute) epoxy or6-minute epoxy. When
30-minute epoxy is specified it is highly recommended that
you use only 30-minute (or 45-minute) epoxy, because you
will need the working time and/or the additional strength.

•

Photos

and

sketches

are placed before the step they
refer to. Frequently you can study photos in following steps
to get another view of the same parts.

Fuse = Fuselage

Stab = Horizontal Stabilizer

Fin = Ver tical Fin

LE = Leading Edge

TE = Trailing Edge
LG = Landing Gear
Ply = Plywood

" = Inches

mm = Millimeters

SHCS = Socket Head Cap Screw

COMMON ABBREVIATIONS

IMPORTANT BUILDING NOTES

EASY-TOUCH™BAR SANDER

A flat, durable, easy to handle sanding tool is a necessity
for building a well finished model.Great Planes makes a
complete range of Easy-Touch Bar Sanders and
replaceable Easy-Touch Adhesive-backed Sandpaper.
While building the P-38 Profile, two 5-1/2" [140mm] Bar
Sanders and two 11" [280mm] Bar Sanders equipped
with 80-grit and 150-grit Adhesive-backed Sandpaper
were used.

Here’s the complete list of Easy-Touch Bar Sanders and
Adhesive Backed Sandpaper:

5-1/2" [140mm] Bar Sander (GPMR6169)
11" [280mm] Bar Sander (GPMR6170)
22" [560mm] Bar Sander (GPMR6172)
33" [840mm] Bar Sander (GPMR6174)
44" [1120mm] Bar Sander (GPMR6176)
11" [280mm] Contour Multi-Sander (GPMR6190)

12' [3.66m] roll of Adhesive-backed 80-grit sandpaper
(GPMR6180)
150-grit (GPMR6183)
180-grit (GPMR6184)
220-grit (GPMR6185)
Assortment pack of 5-1/2" [140mm] strips (GPMR6189)

We also use Top Flite 320-grit (TOPR8030, 4 sheets) and
400-grit (TOPR8032, 4 sheets) wet-or-dry sandpaper for
finish sanding.

5

1.Unroll the plan sheet. Re-roll it inside out to make it 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 ballpoint
pen, lightly write the part name or size on each piece to
avoid confusion later. Use the die-cut drawings shown on
page 7 to identify the die-cut parts and mark them before
removing them from the sheet. Save all scraps. 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 die­cutting irregularities or slivers.

GET READY TO BUILDTYPES OF WOOD

6

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

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

METRIC CONVERSIONS

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

7

DIE-CUT DRAWINGS

8

❏ 1.Unroll the plan sheets.Roll them inside out so they will

lie flat.

❏ 2.Position the wing plan so the stab plan is over your flat

building board. Cover the plan with Great Planes Plan
Protector™or wax paper so glue will not adhere.

❏ 3. From two of the straightest 1/4" x 1/2" x 24" [6mm x

13mm x 610mm] balsa sticks, cut the stabilizer leading
and trailing edge to match the stabilizer plan.Pin the

leading

and trailing edge over the plan.

❏ 4. From 1/4" x 1/4" x 30" [6mm x 6mm x 762mm] balsa

sticks, cut and glue the stabilizer ribs between the leading
and trailing edge.

❏ 5. Locate the four die-cut 1/8" [3mm] balsa S3 stabilizer

tips. Make two sets of S3’s by gluing two of the 1/8" [3mm]

S3’s together to make 1/4" (6mm) thick S3’s.

❏ 6. Glue the S3 stabilizer tips to the trailing edge of the

stabilizer.

❏ 7. Locate the four die-cut 1/8" [3mm] balsa S1 and S2

stabilizer tips. Glue two of the S1’s together and two of the

S2’s together to make two 1/4" (6mm) thick S1’s and S2’s.

❏ 8. Pin S1 to the stabilizer tip plan. Pin and glue S2 to S1.

❏ 9. From the 1/4" x 3" x 5" [6mm x 76mm x 127mm] balsa

sheet, cut two stabilizer joiners as shown on the stabilizer
plan. Glue the joiners to S2.The stabilizer tips will be glued
to the stabilizer later when the main booms are attached to
the wing.

Build the Stabilizer

BUILD THE T AIL SURF ACES

❏ 10.Remove the stab from your b uilding 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.

❏ 1. From two 1/4" x 1/2" x 24" [6mm x 13mm x 610mm]

balsa sticks, cut the elevator leading and trailing edge to
match the elevator plan. Pin the leading and trailing edge
over the plan.Cut and glue the elevator ends to the leading
and trailing edge.

❏ 2. From a 1/4" x 1/4" x 30" [6mm x 6mm x 762mm] balsa

stick, cut and glue the elevator ribs between the leading
and trailing edge.

❏ 3. From the remaining 1/4" x 1/2" x 24" [6mm x 13mm x

610mm] balsa stick, cut and glue gussets in the corner
between the elevator leading edge and elevator ends.

❏ 4. Remove the elevator 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.First sand both sides of the stab and elevator
flat and even.Then, round the edges of the stab and

elevator

as shown on the plan.

❏ 1. Locate the four die-cut 1/8" [3mm] balsa R1 rudder

trailing edges. Glue two of the R1’s together to make two

1/4" [6mm] thick R1’s.

❏ 2. Position the fuse plan so the rudder plan is over your

flat building board. Cover the plan with Great Planes Plan
Protector or wax paper so glue will not adhere.

❏❏3. Pin the rudder trailing edge over the plan.

❏❏4. From remaining 1/4" x 1/2" x 24" [6mm x 13mm x

610mm] balsa sticks, cut the rudder leading edge to match
the rudder plan. Pin and glue the leading edge to the die-cut
trailing edge.

Build the Rudder

Build the Elevator

9

❏❏5. From the 1/4" x 1/4" x 30" [6mm x 6mm x 762mm]

and 1/8" x 1/4" x 24" [3mm x 6mm x 610mm] balsa sticks,
cut and glue ribs to the leading and trailing edges.

❏❏6.Remove the rudder 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. Use a bar sander to sand both sides of the
rudder flat and even.

❏ 7. Return to step 2 and build the second rudder.

Start by building the left wing panel upside-down over the
left wing panel plan so your progress matches the photos.

❏ 1. Match the four 1/8" x 1/4" x 24" [3mm x 6mm x 610mm]

basswood main spars so any w arps will counteract each

other.

❏ 2. Cover the wing panel plan with waxed paper or Great

Planes Plan Protector.

❏❏3. Glue two of the die-cut 3-ply W-3 ribs together.

❏❏4. Glue the die-cut 3/32" [2mm] balsa W-3B ribs to

both sides of the aft end of the W-3 rib.

❏❏5. Position one of the main spars over the plan. Align

the end of the main spar with the outboard edge of rib W-7.

Build the Wing Panels

BUILD THE WING

10

❏❏6. Pin the die-cut 1/8" [3mm] balsa sub-trailing edge

over the plan, perpendicular to the building board. Position
the die-cut ribs on the main spar, inserting the aft end of the
ribs in the notches of the sub-trailing edge.

❏❏7.Note which side of rib W-3 faces the root of the

wing.

Remove W -3 and glue the die-cut 3-ply W -3C rib to this side.

❏❏8. Reinstall W-3 on the main spar and sub-trailing

edge. Repin the main spar to your building board with the
pins outside of rib W-1. Pin rib W-7 perpendicular to your
building board.Remove the remaining pins holding the main
spar to the building board. This will allow the shear web to
be installed in the next step.

❏❏9.Glue the two-piece die-cut 3-ply shear web

together.
Use a straightedge to keep the two pieces aligned.From the
root rib, insert the shear web through the center of the ribs.
Carefully rotate it so that the “T”on the shear web is towards
your building board and the notches are aligned with the
ribs.Position the shear web so that it is as far bac k in the rib
as possible. The shear web will be centered on the main
spar.Pay special attention at ribs 1 and 2.

❏❏10.Pin the ribs to your building board next to the main

spar. Once the shear web is in position, glue it to the ribs
and the main spar.

❏❏11. With the ribs fully seated in the sub-trailing edge,

glue the ribs to the sub-trailing edge.

❏❏12.T est fit the second main spar in the ribs.Make sure

it is flush with the top of the ribs. Once satisfied with the fit,
remove the spar and apply a bead of medium CA along the
top edge of the shear web and the main spar notch of the
ribs and reinstall the spar.

11

❏❏13. Position the die-cut 3-ply sub-leading edge over

the tabs on the front of the ribs.As you glue the sub-leading
edge to the ribs, make sure the sub-trailing edge and main
spar is down on your building board.

❏❏14. Glue the two die-cut 3-ply wing tip pieces together

as shown on the plan.

❏❏15. Glue the wing tip to the sub-trailing edge, shear web

and rib W-7.

❏❏16.Using a sanding bar with 220-grit sandpaper,

lightly
sand the top of the ribs, main spar, sub-leading edge and
sub-trailing edge all flush.

❏❏17.Use epoxy to glue the hardwood landing gear rail

in
the notches of ribs W-2 and W-3. Make sure that the landing
gear rail protrudes above the ribs by 1/16" [1.6mm] and is
flush with the side of rib W-3. Before the epoxy hardens,
wipe off any excess from rib W-2 using a paper towel
dampened with denatured alcohol.

❏1.From one of the 1/16" x 3" x 30" [1.6mm x 76mm x

762mm]
balsa sheets, cut a 1/16" x 5/8" x 30" [1.6mm x 16mm x
762mm] trailing edge strip. Glue the strip to the sub-

trailing

edge, ribs W-1 through W-7 and the wing tip.

❏❏2.T rue one edge of a 1/16" x 3" x 24" [1.6mm x 76mm

x 610mm) balsa sheet to make a leading edge sheet.The
sheet is installed from the middle of the main spar to the
sub-leading edge by first applying medium CA along the
front half of the main spar, the edge of the ribs and the sub­leading edge. Position the sheet on the main spar and
slowly press the sheet down onto the ribs and leading edge.
Use a sanding bar to press the sheet down evenly.

Sheet the Wing Panels

12

❏❏

3. From a second 1/16" x 3" x 30" [1.6mm x 76mm x
762mm] balsa sheet, make a trailing edge sheet to fit from
rib W-1 to W-3. Cut the sheet 2-1/8" [54mm] wide. Glue the
sheet to the trailing edge strip and the top of the ribs.

❏❏4. Remove the wing panel from your building board.

Check all the glue joints. Pay special attention to the joint
between the shear web and the main spars.The shear web
must be securely glued to the main spar.

❏❏5. Tr im the sheeting flush with rib W-1 and the sub-

leading edge.

❏❏6. Use epoxy to glue the 3/4" x 3/4" x 3/4" [19mm x

19mm x 19mm] hardwood landing gear torque block to
the landing gear rail and rib W-2.

❏ 7. Return to step 2 and build the right wing panel.

❏ 1. Use epoxy to glue the two die-cut 1/16" [1.6mm]

plywood
wing joiners together, aligning the joiners at the center.
Before the epoxy hardens, wipe off any excess with a paper
towel dampened with denatured alcohol.

❏ 2. Assemble and glue the two die-cut 3-ply R7A and one

R1B rib jigs.

Join the Wing Panels

13

❏ 3. Fit the R7A jigs under the W-7 ribs and the R1B jig

under the W-1 ribs so that the aft edge of the jigs are flush
with the trailing edge of the wing. Apply 30-minute epoxy to
the root ribs and use clamps to hold the wing halves
together. Apply epoxy to the front of the wing joiner and
insert it through W-1 as shown.The forward joiner is against
the shear web and the aft joiner is against the main spars.
Wipe off any excess epoxy and use clamps to hold the
joiner in position until the epoxy cures.

❏ 4. Use epoxy to glue the die-cut 3-ply sub-leading edge

joiner in the front of the W-1 ribs and the sub-leading edge.

❏ 5. Use a planer and bar sander to trim the sub-trailing

edge flush with the top of the ribs. Taper the tip of the sub­trailing edge so that the trailing edge strip can be glued to
the wing tip.

❏ 6. Use a bar sander to taper the trailing edge sheeting to

match the taper on ribs W-1 through W-3. See the wing
cross-section on the wing plan.

❏ 7. From the 1/2" x 1/2" x 12" [13mm x 13mm x 305mm]

balsa stick cut six 1-1/2" [38mm] long hinge blocks .Glue the
hinge blocks in position against the sub-trailing edge.

❏ 1.With the wing setting on the wing jigs, cut and glue 5/8"

[16mm] balsa sub-trailing edge strips to the top of the ribs
and the sub-trailing edge.

Sheet the Top of the Wing

14

❏ 2. From the remaining 1/16" x 3" x 30" [1.6mm x 76mm x

762mm] balsa sheet, used to make the bottom trailing edge
sheet, and a second 1/16" x 3" x 30" [1.6mm x 76mm x
762mm] balsa sheet, make two top trailing edge sheets.
Glue the top trailing edge sheets in position.

❏ 3.Use 320-grit sandpaper to roughen the 1/8" x 5" [3mm

x 127mm] plastic tube. Cut three 5/8" [16mm] long throttle
torque rod bearings from the 1/8" x 5" [3mm x 127mm]

plastic tube.

❏ 4.Lay the 1/8" x 17-1/2" [3mm x 445mm] throttle torque

rod over the plan and mark the location of the four 1/8"
[3mm] wheel collars.Use a file to make a flat spot at each

wheel collar location.Make sure the flats are all on the same
side of the throttle torque rod.

❏ 5. Insert the throttle torque rod through the wing ribs and

position the wheel collars and plastic bearings on the rod.

❏ 6. Use epoxy to glue the die-cut 3-ply W-1A and W-3A

sub-ribs to both sides of the W-1 and W-3 ribs. Also glue

the throttle torque rod bearings to the ribs. Be careful to not
get epoxy in the plastic bearings. A light coat of grease on
the torque rod will prevent the epoxy from sticking to the
torque rod.Before the epoxy hardens, mak e sure the throttle
torque rod rotates freely.

❏ 7. Position the torque rod in its correct location. Apply a

drop of thread lock to a 4-40 set screw and secure the one
wheel collar, that will not ha v e a torque rod horn installed on
it, on the throttle torque rod. Make sure that the set screw is
tightened on the flat spot on the throttle torque rod.

❏ 8. With the three remaining wheel collars in position, cut

slots in the bottom sheeting under the wheel collars.

15