Great Planes GPMA0240 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. 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.

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.

READ THROUGH THIS MANUAL BEFORE
STARTING CONSTRUCTION. IT CONTAINS

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

©Copyright 1998 ULT4P03 V1 1

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

Introduction

Precautions.......................................................................3

Decisions You Must

Engine Selection

Preparations

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

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

Optional Supplies and Tools
Types

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

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

Get Ready to

Inch/Metric Ruler..........................................................5

Die-Cut Patterns...................................................... 6&7

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

Build

Build the Elevator.........................................................8

Build the Fin. .

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

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

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

Fit the Torque Rods

Install Tailwheel Bracket on Rudder...........................11

Build the Bottom Wing...................................................12

Wing Preassembly.....................................................12

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

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

Sheet the Bottom of the Wing....................................15

Complete the Bottom Wing........................................16

Build

Build

the Fuselage

Fuselage Preassembly.. ...........................................18

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

Install the Formers

Mount the Wing on the Fuselage...............................22

Install the Stabilizer and Fin .... .................................23

Assemble the Turtledeck............................................24

Build the Top Deck.....................................................25

Build the Top Wing.........................................................27

Wing Preassembly.....................................................27

Build

Sheet the Top of the Wing..........................................30

Install the Aft Root Ribs..............................................30

Finish Sheeting the Top

Sheet the Bottom of the Wing.. .................................31

Complete the Bottom of the Wing ..............................32

Build

Engine
Assemble the Plastic Parts

Assemble the Wheel Pants........................................34

Assemble the Cowl

Balance the Model Laterally..........................................37

Covering.......................................................................37

Prepare the Surface..................................................37

Covering Technique...................................................37

Suggested Covering Sequence................................38

......................................................................3

Make................................................3

.........................................................3

.....................................................................3

........................................4

of

Wood

.......................................................4

Build.......................................................5

the Stabilizer

the Ailerons

the Wing ...

the Ailerons

Installation

.......................................................8

............................................................9

...................................................11

.......................................................17

.........................................................18

.....................................................20

....

..............................................27

of

the Wing

.......................................................33

.........................................................33

...........................................34

...................................................36

..........................31

Painting........................................................................38

Final

Hookups and Checks

Install

the Hinges

Install the Hardware...................................................39

Attach the Canopy .....................................................39

Radio Installation ...........................................................40

Install the Rudder, Elevator and Throttle Servo .........40

Install the Aileron Servo

Check the Wing Incidence.............................................43

Set the Control Throws.................................................43

Balance

Preflight...........................................................................44

AMA Safety Code............................................................46

Flying...............................................................................46

2-View Drawing

Your Ultimate 40 is not a toy, but rather a sophisticated,
working model that functions very much like a full size
airplane Because of its realistic performance, the
Ultimate 40, if not assembled and operated correctly,
could possibly cause injury to yourself or spectators and
damage property.

If this is your first biplane model, we recommend that you
get help from an experienced, knowledgeable modeler with
your first flights. You'll learn faster and avoid risking your
model before you're ready to take the controls for yourself.

For information on flying clubs in your area, you can

contact the national Academy of Model Aeronautics (AMA),
which has more than 2,500 chartered clubs across the
country Contact AMA at the address or toll-free phone
number below:

Your

Model

Charge the Batteries..................................................44

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

Find a Safe Place to
Ground Check the Model

Range Check Your Radio...........................................45

Engine Safety Precautions........................................45

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

Radio

Control............................................................46

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

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

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

Flight

Log...................................................................47

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

.......................................................38

.......................................................44

...............................................Back

...........................................38

.............................................42

Fly.............................................45

...........................................45

Cover

Academy of Model Aeronautics

5151 East Memorial Drive

Muncie, IN 47302-9252

Tele [phone]

Fax [phone]

2

The Great Planes Ultimate 40 is a high performance,
propeller-driven sport biplane that closely resembles the
full size Ultimate The Ultimate 40 is very stable and
forgiving, allowing even intermediate skill level pilots to
enjoy it

This is not a beginner's airplane! While the Ultimate 40

is easy to build and flies great, we must discourage you
from selecting this kit as your first R/C airplane It lacks the
self-recovery characteristics of good basic trainers such as
the Great Planes PT" Series On the other hand, if you
have already learned the basics of R/C flying, and you are
able to safely handle a 40-size low wing airplane, the
Ultimate 40 is an excellent choice to try your skills at flying
a biplane.

Remember: Take your time and follow directions to end
up with a well-built model that is straight and true.
Please inspect all parts carefully before starting to build!
If any parts are missing, broken or defective, or if you

have any questions about building or flying this
airplane, please call us at [phone]. If you are
calling for replacement parts, please reference the part
numbers and the kit identification number (stamped on
the end of the carton) and have them ready when calling.

1 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 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,

and a correctly sized engine and components (fuel tank,
wheels, etc ) throughout your building process.

4. You must properly 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 you must
make certain 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.

NOTE We, as the kit manufacturer, can provide you
with a top quality kit and great instructions, but ultimately
the quality of your finished model depends on how you

build it, therefore, we cannot in any way guarantee
the performance of your completed model, and no
representations are expressed or implied as to the
performance or safety of your completed model.

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

D Four-channel radio with four servos
D Engine - See Engine Selection above
D Propeller (Top Flite Power Point"), Refer to your

engine's instructions for proper size
D Fuel tank 10oz (GPMQ4104)
D Medium fuel tubing (GPMQ4131)
D 2-1/4" Main wheels (GPMQ4222)
D 1"Tailwheel(GPMQ4241)
D Top Flite MonoKote (Approximately 3 rolls)
D Pilot figure (Williams Bros #185)
D 1/4" Latex foam rubber padding (HCAQ1000)
D Switch and charge jack (GPMM1000)
D Top Flite LustreKote" Paint - See Painting (page 37)
D 1/16" Wing seating tape (GPMQ4422)
D 6" Servo extension
D 2-1/2" White spinner (GPMQ4520)
D Fuel fill valve (GPMQ4160)

3

These are the building tools that are required. We
recommend Great Planes Pro" CA and Epoxy glue.

D 2 oz. Pro CA (Thin, GPMR6003)
D 2 oz Pro CA+ (Medium, GPMR6009)
D 1 oz Pro CA- (Thick, GPMR6014)
D 6-Minute Pro Epoxy (GPMR6045)
D 30-Minute Pro Epoxy (GPMR6047)
D Hand or electric drill
D Sealing iron (TOPR2100)
D Heat gun (TOPR2000)
D Hobby saw
D Hobby knife, #11 Blades
D Razor plane (Master Airscrew®)
D Pliers (Common and Needle Nose)
D Screwdrivers (Phillips and flat tip)
D T-pins (HCAR5150)
D 60" Retractable Tape Measure (HCAR0478)
D Straightedge with scale
D Masking tape (TOPR8018)
D Sandpaper (coarse, medium, fine grit)
D Easy-Touch" Bar Sander (or similar)
D Plan Protector (GPMR6167)
D Lightweight balsa filler such as Hobbico^ HobbyLite"

(Hobbico HCAR3400)
D 1/4-20 Tap and Drill (GPMR8105)
D IsopropyI rubbing alcohol (70%)
D White body putty (Squadron SQUR1500)
D Ballpoint pen
D 90° Building square (HCAR0480)
D Micro balloons (TOPR1090)
D Canopy glue
D Drill bits 1/16", 5/64", 3/32", 7/64", 1/8", 9/64", 5/32",

3/16", 13/64", 1/4", 5/16", 3/8"

D Builders triangle set (HCAR0480)

Custom sanding blocks can be made from balsa or hardwood
blocks and dowels for sanding difficult to reach spots

D CA Applicator Tips (HCAR3780)
D Epoxy brushes (GPMR8060)
D Epoxy mixing sticks (GPMR8055)
D CA Debonder (GPMR6039)
D Hot Sock "(TOPR2175)
D Single-edge razor blades (HCAR0312)
D Curved tip canopy scissors for trimming plastic parts

(HCAR0667)

D 4 oz Pro Wood Glue (GPMR6161)

Balsa Basswood Plywood

Elev = Elevator

LE = Leading Edge (front)
Ply = Plywood
TE = Trailing Edge (rear)

4

Fuse = Fuselage

LG = Landing Gear

Stab = Stabilizer

" = Inches

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"

Machine screws are designated by a number, threads per
inch and a length. For example 4-40 x 3/4"

When you see the term "test fit" in the instructions, it
means you should first position the part on the assembly
without using any glue and then slightly modify or sand
the part as necessary for the best fit

Whenever the instructions tell you to glue pieces together,
CA or epoxy may be used 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 or the additional strength.

D 1. Unroll the plan sheets Reroll the plan sheets inside
out to make them lie flat Place wax paper or Great Planes

Plan Protector over the plan to prevent glue from sticking to

the plan.

D 2 Remove all parts from the box As you do, determine
the name of each part by comparing it with the plan 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 patterns

shown on pages 6 and 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 remove, do

not force them' Instead, cut around the parts Use your

Easy-Touch Bar Sander or sanding block to lightly sand
the edges to remove any die-cutting irregularities.

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

(stabilizer) and hardware Resealable food storage bags
are handy to store parts in as you sort, identify and
separate them into subassemblies.

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 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 being built upside-down).

Inch Scale

Metric Scale

5

6

7

Glue together the pairs of die-cut 1/8" balsa stabilizer
center S-1, fin bottom S-2, rudder bottom R-3 and

rudder tip R-4 to make 1/4" thick parts.

D 3 Remove the stab from your building board Inspect all
the glue joints and add CA to any joints that don't look
strong Sand the LE and TE flush Sand the entire top and
bottom surfaces of the stab until they are flat and even Be
careful that you don't sand any area of the stab too thin.

D 1 Pin the die-cut 1/4" balsa stabilizer center S-1 over
the stabilizer plan Cut the stab outer frame from a

1/4" x 1/2" x 36" balsa stick, allowing approximately 1/16"
extra at the joints The joints will be sanded flush after the
stab is removed from the building board Glue the outer
frame and stab center together and pin it in position over
the plan Use the plans or a straightedge as a guide to
make sure the stab TE is straight as you glue it in position.

Note: Refrain from using excessive accelerator 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 your building board right away, we recommend
using no accelerator at all.

D D 1 Cut a 1/4" x 1/2" x 36" balsa stick to make the
elevator LE and TE Pin the LE and TE in position over the
plan Allow the LE to extend 1/16" past the root and the TE
to extend 1/16" past the tip.

D D 2. Cut the root and tip frame from the remaining
1/4" x 1/2" x 36" balsa stick Glue and pin the elevator in
position over the plan.

D D 3 Cut gussets from a 1/4" x 1/2" x 36" balsa stick
and glue them in place

D 2 Make the 1/8" stab ribs from a 1/8" x 1/4" x 36" balsa
stick. Glue the ribs in position.

Hint: Use a sharp, single-edge razor blade to cut the
stab ribs.

D D 4 Make the 1/8" elevator ribs from a 1/8" x 1/4" x
36" balsa stick and glue them in place

8

D D 5. Remove the elevator from your building board.
Inspect all the glue joints and add CA to any joints that
don't look strong. Sand the LE,TE, root and tip flush. Sand
the entire top and bottom surface of the elevator flat and
even. Be careful that you don't sand any area too thin.

D 6. Go back to step 1 and build the second elevator
following the same procedure.

D 3. Remove the fin from your building board. Inspect all
the glue joints and add CA to any joints that don't look
strong. Sand the joints flush and the entire top and bottom
surfaces of the fin flat and even. Be careful that you don't
sand any area too thin.

D 1. Pin the die-cut 1/4" balsa fin bottom S-2 over the fin
plan. Cut the fin outer frame from a 1/4" x 1/2" x 36" balsa
stick, allowing approximately 1/16" extra at the joints. Glue
the outer frame and fin bottom together and pin it in
position over the plan. Use the plans or a straightedge as a
guide to make sure the fin TE is straight as you glue it in
position.

D 1. Pin the die-cut 1/4" balsa rudder bottom R-3 and
rudder tip R-4 over the rudder plan. Cut the rudder outer
frame from a 1/4" x 1/2" x 36" balsa stick, allowing
approximately 1/16" extra at the joints. Glue the outer
frame, rudder bottom and rudder tip together and pin it in
position over the plan. Use the plans or a straightedge as a
guide to make sure the rudder LE is straight as you glue
it in position.

D 2. Cut the rudder ribs and diagonal braces from the
remaining 1/8" x 1/4" x 36" balsa stick. Glue the ribs and

braces in position.

D 2. Cut the top two fin ribs from the remaining
1/8" x 1/4" x 36" balsa stick. Cut the bottom rib from a
1/4" x 1/2" x 36" balsa stick. Glue the fin ribs to the fin LE
and

TE.

D 3. Cut the remaining 1/4" x 1/2" x 36" balsa stick to
make the LE gusset. Glue the gusset in position.

D 4. Remove the rudder from your building board. Inspect

all the glue joints and add CA to any joints that don't look
strong. Sand the joints flush and the entire top and bottom
surface of the rudder flat and even. Be careful that you
don't sand any area too thin.

9

D 1. Place the stab and elevators over their locations on
the plan and lightly mark the hinge locations on the TE of
the stab and LE of the elevators.

D 4. Cut the hinges for the elevators and rudder from the
supplied 2" x 9" hinge material. Use the hinge drawing
on the fuse plan as a guide. Trim off the corners and
temporarily join the elevators to the stabs with the hinges,
adjusting any hinge slots if necessary. Do not glue in the

hinges until you are instructed to do so.

D 2. Mark the centerline of the hinges on the stab's TE
and elevator's LE using the following centerline method.

HOW TO MARK A CENTERLINE

It's important that the hinges are centered and parallel to

the part you are hinging. The best way to start is by

accurately marking the hinge centerline.

A. Lay the stab and a ballpoint pen on a flat surface.

Mark a "test line" on the trailing edge of the stab.

D 5. Return to step 1 and use the same procedure to
hinge the rudder and fin.

D 1. Refer to the Expert Tip that follows and shape the LE
of the elevators and rudder to a "V" shape as shown on
the plans.

HOW TO BEVEL THE LEADING EDGE

B. Flip the stab over and mark another line in the same

location as the first. If you see only one line, then it is
on center. Proceed and mark the centerline at each
hinge location. If you see two lines, use playing cards
or business cards to adjust the height of the pen until

you can mark the centerline.

C. Use the same technique to mark the centerline along

the entire length of both elevators.

D 3. Cut the hinge slots in the elevator and stab 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.

A. Place the leading edge of one of the elevators on your

work surface and use your ballpoint pen to mark a
"bevel to" line on both sides about 1/8" high.

B. Using the bevel to lines and the centerline as a guide,

make the "V" on the leading edge of the elevators with
a razor plane or your bar sander.

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

10

D 3 Draw a centerline on the LE of the stab and fin and on
the TE and tip of the elevators and rudder Sand a radius
on the edges as shown on the plan using the centerline as
a guide to keep the radius symmetrical Do not round the
TE of the stab or fin.

HOW TO CUT A GROOVE FOR A TORQUE ROD

A. Use a hobby knife to sharpen the inside of a piece of

1/8" brass tube Roll the tube as you carve the end.

D 1 Position the stab and elevators over the fuselage top
view Mark the location of the elevator joiner on the elevators.

D 2 Drill 3/32" pilot hole into the elevator LE, on the

centerline, at the torque rod marks As you drill the holes
keep the drill aligned with the top and bottom surfaces of
the elevator Enlarge the holes with a 1/8" drill bit.

B. Use the sharpened tube to carefully gouge the leading

edge You II have to make several passes to make the
recess deep enough for the torque rod.

D 1 Position the rudder over the plan and align the
tailwheel bracket over the rudder Mark the tailwheel
bracket "arm" location on the LE of the rudder. Drill a 7/64"

hole, 3/4" deep at the mark.

D 3 Cut a 1/8" groove in the leading edge of both
elevators to recess the joiner wire (see expert tip that
follows) Do not glue the joiner wire in position at this time.

D 2 Cut a groove from the tailwheel bracket hole to the
bottom of the rudder that will allow the nylon tailwheel
bearing to fit flush with the LE of the rudder Do not glue
the tailwheel bracket in at this time.

11

The Ultimate 40 bottom wing is built as one piece.

D 1. Pin the die-cut 3/32" balsa ribs R-1 in position over
the main spar.

Note: The jig tabs should be contacting the plan. Use
small T-pins to pin the aft jig tabs to the building board

over their location on the plan.

D 1. Use 30-minute epoxy to glue together the die-cut 1/8"
plywood ribs R-5 and R-6.

TWO WARPED SPARS INSTALLED

THIS WAY WILL RESULT IN A

STRAIGHT WING

TWO WARPED SPARS INSTALLED

THIS WAY WILL RESULT IN A

WARPED WING

D 2. Match sets of 1/4" x 3/8" x 24" balsa wing spars so
any warps will counteract each other.

HOLD KNIFE AT AN ANGLE

WHEN CUTTING APART

LEADING EDGE

D 2. The shaped and notched balsa wing LE and TE are
fastened together by thin strips of balsa. Separate them by
cutting with a hobby knife, as shown in the sketch above.

D 3. Trim the end of two main spars to the angle shown
on the plan. Use 6-minute epoxy to glue the ends of
the main spars together. Before the epoxy cures, use the
cross-pinning technique (see sketch above) to pin the main
spars against the building board.

D D 3. Center the LE vertically on the front of the ribs with
each rib inserted in its respective notch. Use a straightedge
to check that the LE is straight before gluing it in position.

D D 4. Cut the LE at the root as shown on the plan. Save
the piece you cut off for the wing center section.

D 5. Repeat the process to install the other LE.

12

D 6. Position the TE on the aft end of the ribs, flush with
the top and bottom edge of the ribs. Use a straightedge to
check that the TE is straight before gluing it in position.
Trim the root end to match the plan.

D 7. Fit the second TE, trimming the root end to butt
against the first TE. Use a straightedge to check that the
TE is straight before gluing it in position.

D 8. Glue ribs R-1 to the bottom main spar, perpendicular

to the building board.

D 11. Glue the die-cut 3/32" balsa ribs R-4 flush with both
sides of R-5.

D 12. Use 6-minute epoxy to glue rib R-6 to the joiner

and the TE. Make sure that the rib is seated on and

perpendicular to the building board. Glue rib R-5 to the front
of the joiner and spars, perpendicular to the building board
and parallel with the R-1 root ribs.

D 9. Use 30-minute epoxy to glue the 1/8" plywood joiner
between the R-1 root ribs, perpendicular to the building
board. The center of the joiner should be flush to the aft
edge of the main spar and the joiner ends should be flush
with the forward edge of the main spar. Make sure the top
of the joiner is flush with the bottom of the slots for the top
main spar.

D 10. Use 30-minute epoxy to glue the top spar to the
joiner and thin CA to glue the joiner to the ribs. Hold the
spar in place with a weight until the epoxy cures.

D 13. Trim the leftover LE to fit between ribs R-1 and R-5,
centered on the front of ribs R-4. When satisfied with the fit,
glue them in place.

U 14. Use 6-minute epoxy to glue the die-cut 1/8" plywood
leading edge joiner (LEJ), centered vertically, across the

joint between the center LE and the outer LE.

13

D 15 Test fit the die cut 1/8" plywood ribs R-2A and R-2B

in position as shown on the plans Check the fit of the wing
strut between R-2A and the wing spars The strut should fit
snug but be easy to insert and remove When satisfied

with the fit, remove the strut and glue ribs R-2A and R-2B

to

R-1.

D 16 Insert the die-cut 3/32" balsa rib R-3 between the
spars and carefully rotate it into position Glue it to ribs
R-2A, R-2B, the wing spars and the LE and TE.

D 1. Cut the 2" LE and 1" TE sheeting from eight
1/16" x 3" x 24" balsa sheets The LE and TE sheets will be
used on both wings.

D 2 Test fit the LE wing sheet to one wing panel Sand a
slight bevel on the front of the sheet The aft edge of the
sheet should cover the forward half of the main spar The
root end should cover one R-4 and R-5 rib.

D 17 From a 1/16" x 3" x 24" balsa sheet cut and glue
shear webs, perpendicular to the aft edge of the main spars
The shear webs must be glued securely to the main spars.

D 18 Sand the top of the wing so that the spars, shear
webs and TE are flush with the top of the ribs.

D 3 Remove any pins that are holding the wing to the
building board in front of the main spar You may need to
place weights on the wing to keep the main spars flat
against the building board Position the front of the LE
sheet against the LE and glue it in position with thin CA.

D 4 Carefully lift the sheet away from the ribs and apply a
bead of medium or thick CA to the top of the ribs Working
quickly, pull the sheet back toward the main spar as you

press it down against the ribs and the main spar.

14

D 5. Use thin CA to glue the LE sheet to the main spar.

D 6. Fit and glue the second LE sheet to the other wing
panel, following the same procedure.

D 7. Glue the 1/16" TE sheet, cut in step 1, to the TE and

the top of the ribs

D 9. From 1/16" x 3/16" x 30" balsa stick, cut and glue cap
strips to the top of the R-1 ribs. The edge of the cap strip
on the R-1 tip rib should be flush with the side of the rib.
Use two cap strips, edge-glued at the center of rib R-2A on
the double rib, for the strut. Trim the cap strip over the slot
for the strut.

Hint: A single-edge razor blade works well for this type
of cutting.

D 10. Remove the wing from your building board. Cut and

sand the LE, TE, main spars and top sheeting flush with the

side of tip rib R-1.

The bottom of the wing is sheeted following the same
procedure as the top of the wing.

D 8. Use a 1/16" x 3" x 30" balsa sheet to make the center
sheeting between the LE sheet and the TE sheet. Save
the remaining sheeting for the bottom center sheeting. The
center sheeting filler is made from a 1/16" x 3" x 24"
balsa sheet.

Note: See the plans for clarity. Before you glue the center
sheeting in position, remove any T-pins from under
the sheeting.

D 1. Use a hobby knife and sanding bar to remove the jig
tabs on the bottom of the ribs. Sand the TE, main spars,
shear webs and the top of the ribs to blend them together.

D 2. Cut out the aileron servo opening in the top center
sheeting using the aileron servo cutout in rib R-6 as a
guide. Make the opening slightly smaller than the servo
cutout in the rib. The opening will be enlarged when the
servo tray is installed.

15