Great Planes GPMA0502 User Manual
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 buyers are not prepared to accept the liability associated with the use of this product, they are
advised to return this kit immediately in new and unused condition to the place of purchase.
P.O. Box 788 Urbana, IL 61801 (217) 398-8970
GAROP04 10/96 V1 0 Entire Contents © Copyright 1996
Introduction...................................................................3
Precautions....................................................................3
Decisions You Must
Preparations.................................................................4
Required Accessories..............................................4
Building Supplies and Tools.....................................4
Optional Supplies and Tools.....................................4
Common Abbreviations............................................4
Types
of
Wood
Building Notes. . . . ..................................................5
Metric Conversions ..................................................5
Die-Cut Patterns................................................6 & 7
Get Ready to
Build the Tail Surfaces..................................................8
Make the Stabilizer Center.......................................8
Build the Stabilizer ...................................................8
Build the Elevator...................................................10
Build the Fin...........................................................10
Build the Rudder.....................................................11
Hinge the
Finish the Tail Surfaces..........................................12
Build
the Bottom Wing
Bottom Wing Preassembly.....................................13
Build the Wing Panels............................................13
Sheet the Top of the Wing......................................15
Sheet the Bottom
Finish the Wing Panel
Joining the Wing Panels.........................................18
Build the Ailerons ...................................................18
Build the Top Wing......................................................19
Top Wing Preassembly ..........................................19
Build the Wing Panels............................................20
Sheet the Bottom of the Wing ................................21
Sheet the Top of the Wing......................................22
Finish the Wing Panel ...........................................23
Joining the Wing Panels.
Joining the Wing Panels.........................................23
Build the Fuselage ......................................................25
Fuselage Pre-Assembly. .......................................25
Assemble the Fuselage Sides................................26
Build the Turtledeck................................................30
Attach the Bottom Wing .........................................33
Attach the Stabilizer and Fin ..................................34
Finish the Turtledeck..............................................35
Attach the Top Wing........ ......................................35
Attach the Aileron Servos and Control Horns. .... 36
Install the Rudder and Elevator Servos..................37
Assemble the Wheel Pants....................................37
Assemble the Cowl ................................................38
Covering...........................................................................40
Preparing the Surface............................................40
Covering Technique ...............................................41
Suggested Covering Sequence .............................41
Painting............................................................................41
Tail
Make
............................................3
.........................................................4
Build...................................................8
Surfaces
..........................................12
...............................................13
of
the Wing
............................................17
................................16
Final Hookups and Checks.......................................42
Install
the Hardware
Attach the Canopy..................................................42
Assemble the N-Struts................................................43
Balance the Model Laterally.......................................44
Adjustments
Adjusting the Wing .................................................44
Make the Aileron Connecting Pushrods.................45
Set the Control Throws...............................................45
Balance the Model .................................................46
Preflight..........................................................................46
Charge the Batteries
Balance the Propeller.............................................46
Find a Safe Place to Fly.........................................46
Ground Check the Model .......................................47
Range Check
Engine Safety Precautions.....................................47
AMA Safety Code
General
Radio Control.........................................................48
Flying............................................................................48
Takeoff....................................................................48
Flight.....................................................................48
Landing..................................................................48
Appendix...................................................................49-51
Two-View Drawing ........................................Back Cover
Your Giant Aeromaster is not a toy, but rather a
sophisticated, working model that functions very much like
an actual airplane
Because of its realistic performance, the Giant
Aeromaster, if not assembled and operated correctly,
could possibly cause injury to yourself or spectators and
damage property
We recommend that you have at least built and flown a
.60 size low wing taildragger before attempting to fly the
Giant Aeromaster Even though the Aeromaster is easy to
build and fly, it will not recover like most trainers. If you are
an experianced pilot you will find the Giant Aeromaster a
real pleasure to fly
For information on flying clubs in your area you can
contact the national Academy of Model Aeronautics (AMA),
which has more than 2,300 chartered clubs across
the country.
Contact AMA at the address or toll-free phone number below:
Or via the internet at: http://www.modelaircraft.com
................................................................44
..................................................................47
................................................42
..............................................46
Your
Radio
......................................47
........................................................47
Academy of Model Aeronautics
5151 East Memorial Drive
Muncie, IN 47302-9252
Tele. (800) 435-9262
Fax (317) 741-0057
2
Congratulations' Thank you for purchasing the Great
Planes Giant Aeromaster!
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
This aircraft is a large scale vesion of the Great Planes
60-size Super Aeromaster It's easy to build, extremely
aerobatic and has no "bad habits," making it a great
airplane for hot-dogging Its 73" wingspan makes it
International Miniature Aircraft Association* (IMAA) legal
*IMAA is an organization that promotes non-competitive
flying of giant scale models.
IMAA
International Miniature Aircraft Association
205 S Hilldale Road
Salina, KS 67401
This is not a beginner's airplane! While the
Aeromaster 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 60-size low
wing taildragger, the Giant Aeromaster is an excellent
choice to improve your skills and get into giant scale.
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 (217) 398-8970 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.
Note: We, as the kit manufacturer, can 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
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 model, please give us a call at (217) 398-8970
and we'll be glad to help.
Engine Selection:
The recommended engine size range is as follows:
30 - 45cc displacement Glow Engine
30 - 60cc displacement Gasoline Engine
We strongly recommend the use of a soft engine mount
of some kind, to relieve the stresses on the airframe and
radio system, and to make your aircraft quieter
J-Tec and Soundmaster both produce soft mounts for
large engines.
NOTE: If you are using a gasoline engine, you will need
to make sure that your fuel lines and tank are made
specifically to handle gasoline
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.
Radio System Requirements:
The Great Planes Giant Aeromaster requires a minimum
of six servos Eight servos are required if you prefer to
use a servo for each aileron Our prototype models flew
great with only six servos
Due to the large scale of this aircraft the Giant
Aeromaster requires high torque servos to control the
split elevator (2 required), rudder (1 required) and
ailerons (2 required) (If you prefer a servo for each
aileron four servos are required.) A standard servo may
be used on the throttle only
On our prototypes we used Y-connectors on the elevator
and aileron servos.
3
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 US Engines" 41cc (USEG0041)
D Four-channel radio with six servos
(five high torque and one standard for throttle)
D Y-Connector (2)
D 24" Servo extension (2)
D Propeller (Top Flite Power Point"")
D 16 - 24oz Fuel tank of your choice
D Gas or glow fuel tubing depending on fuel used
D 4" Main wheels (2)
D 1-1/2" Tail wheel (1) (GPMQ4243)
D Covering film (5) rolls (Top Flite MonoKote®)
D 3" Pilot figure (WBRQ2626)
D 1/4" Latex Foam Rubber Padding (HCAQ1000)
D Easy Fueler" fuel fill valve for gas (GPMQ4161)
glow(GPMQ4160)
D Switch and Charge Jack (GPMM1000)
D Fuelproof paint for cowl and wheel pants
(Top Flite LustreKote paint)
D Heavy duty hinges (28)
D 3/16" Axle (2)
D 3/16" Wheel collars (4) (GPMQ4308)
For Mounting the US Engines 41cc
Standard mounting system'
D 1/4-20 x 1-1/4" Flat Head Bolt (4 req )
D 10-32 x 1-1/4" Sockethead Bolt (4 req )
D #10 Washer (4 req)
D 10-32 Blind Nut (4 req.)
Soft mounting system
D J-Tec Snuf-Vibe engine mount (JT-1420SV)
D 1/4-20x2" Sockethead bolts (4 required)
These are the building tools that are required We
recommend Great Planes Pro" CA and Epoxy glue
D Heat gun (TOPR2000)
D Hobby saw (X-Acto razor saw)
D Hobby knife #11 Blades
D
Razor plane (Master
D Pliers
D Screw drivers (Phillips and flat blade)
D Tpins(HCAQ5150)
D String
D Straightedge with scale
D Masking tape (required for construction)
D Sandpaper (coarse medium fine grit)*
D Easy-Touch Bar Sander (or similar)*
D Wax paper
D Balsa filler such as Hobbico" HobbyLite™
(Hobbico #HCAR3400)
D 1/4-20 Tap and tap wrench
D IsopropyI rubbing alcohol (70%)
D White body putty (Squadron #SQUR1500)
D 90° Building square
D Ballpoint pen
D Felt-tip pen
D Round file
D Micro balloons (TOPR1090)
D Canopy glue
Drill bits
D 1 /16" D 1 /8" D 3/16" (Long Bit)
D 5/64" D 9/64" D 13/64"
D
3/32"
D
D 7/64" D 3/16"
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)
Elev = Elevator Fuse = Fuselage
LE = Leading Edge (front) LG = Landing Gear
Lt = Left Ply - Plywood
Rt = Right Stab = Stabilizer
TE = Trailing Edge (rear) " = Inches
Airscrew" 'MASR
5/32"
D
1510)
1/4"
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 4oz Pro Wood Glue (GPMR6161)
D Hand or electric drill
D Sealing iron (TOPR2100)
Balsa Basswood Plywood
4
In our busy workshop we use the Great Planes
Easy-Touch Bar Sanders equipped with Great Planes
#80, #150 and #220-grit Easy-Touch Adhesive-Backed
Sandpaper Great Planes Easy-Touch Bar Sanders are
made from lightweight, rigid, extruded aluminum and can
be found at most hobby shops They are available in five
sizes - 5-1/2" (GPMR6169), 11" (GPMR6170) for most
general purpose sanding, 22" (GPMR6172), 33"
(GPMR6174) and 44" (GPMR6176) for long surfaces such
as wing leading edges. The Easy-Touch Adhesive-Backed
Sandpaper comes in 2" x 12' rolls of 80-grit (GPMR6180),
150-grit (GPMR6183) and 220-grit (GPMR6185) and an
assortment to 5-1/2" long strips (GPMR6189) for the short
bar sander. The adhesive-backed sandpaper is easy to
apply and remove from your sanding bar when it's time
for replacement.
This setup is all that is required for almost any sanding
task. Custom sanding blocks can be made from balsa or
hardwood blocks and sticks for sanding difficult to reach
spots. We also keep some #320-grit wet-or-dry sandpaper
for finish sanding just before covering.
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, then slightly modify the part as
necessary for the best fit.
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 30-minute (or slower) epoxy because you will need
either 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 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 refered 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.
1/64"
1/32"
1/16"
3/32"
1/8"
5/32"
3/16"
1/4"
=
=
=
=
=
=
=
=
.4mm
.8 mm
1.6
mm
2.4mm
3.2
mm
4.0
mm
4.8 mm
6.4mm
3/8"
1/2"
5/8"
3/4"
1"
2"
3"
6"
=
=
=
=
=
=
=
=
152.4
5
9.5 mm
12.7 mm
15.9
mm
19.0
mm
25.4 mm
50.8 mm
76.2
mm
mm
12"
18"
21"
24"
30"
36"
=
304.8 mm
=
457.2 mm
=
533.4 mm
=
609.6 mm
=
762.0 mm
=
914.4 mm
DIE-CUT PATTERNS
6
DIE-CUT PATTERNS
7
D 1. Unroll the plan sheets. Reroll the plans inside out to
make them lie flat.
D 2. Remove all parts from the box. As you do, determine
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 patterns
shown on pages 6 & 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. Zipper-top food storage bags
are handy to store your parts as you sort, identify and
separate them into subassemblies.
D 1. Begin making the stab LE joiner by accurately
cutting the 3/8" x 1-1/2" x 11-7/8" balsa sheet so it is
8-3/4" long and 1 -3/8" wide.
D 2. Use a ballpoint pen and a model building square to
accurately mark the centerline of the stab LE joiner
(4-3/8" from the end). Use your pen to mark another line
on both ends of the stab LE joiner 1-3/16" from one edge.
The following photo shows the locations of these marks.
D 4. Use a hobby knife with a sharp #11 blade or razor
saw to cut along the lines you drew. If necessary, use a
bar sander to true the leading edges you just cut.
Build The Stabilizer
D 1. Place a piece of wax paper over the stab plan so the
glue won't stick to it. Pin the stab LE joiner in position
over the plan. Glue the 3/8" x 2-3/4" x 5-1/8" balsa stab
center to the stab LE joiner. Cut two 3/8" x 1/2" x 30"
balsa sticks 15-3/4" long to make the stab leading
edges. Sand an angle on one end of both sticks to match
the centerline of the stab. Don't cut the tips of the LE'S
yet. Cut and square them with the end of the stab after
you remove it from the plan at step 5. Glue the stab LE'S
to the stab LE joiner with medium CA and pin them in
position over the plan.
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 your building board right away,
we recommend using no accelerator at all.
D 3. Use a straightedge to draw a line connecting the
centerline of the stab LE joiner with the marks on
the ends.
D 2. Cut and sand the angle at both ends of the 3/8" x
3/4" x 14-7/8" balsa stab sub TE. Glue the stab sub TE to
the stab center and pin it in position over the plan. Glue
the 3/8" x 3/4" x 30" balsa stab TE to the stab sub TE 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 and pin it in position.
8
How to Make Stab Skins:
• Wherever practical, prejoin the balsa sheets to make
a "skin" before attaching them to the structure.
D 3. Make the 3/8" stab ribs from a 3/8" x 1/2" x 30"
balsa stick, then glue them in position. Hint: Use a sharp,
single-edge razor blade to cut the stab ribs.
D 4. From a 1/8" x 3/8" x 30" balsa stick, make the 1/8"
cross bracing. Glue them in position between the stab
ribs. We recommend cutting these cross braces with a
single-edge razor blade, too.
• Many modelers like to sort the wood so they can put
the best wood with the most even grain structure on
the top of the stab.
• Make your skin larger than needed to allow for
misalignment. On the stab we suggest leaving 1/4"
extra.
• To make skins, the following steps are suggested:
1. True up the edges of the sheets with a metal
straightedge and a sharp hobby knife or a long
Easy-Touch Bar Sander.
2. Test fit the sheets together to make sure they match well.
3. Method "A": The fastest method for gluing the sheets
together is with thin CA over a flat surface covered with
wax paper. A quick wipe of the joint with a fresh paper
towel will remove most of the excess glue and make
sanding easier. Mark the poorest surface with an "I" as
the inside of the sheet.
Method "B": An alternate method for gluing the pieces
that make up the skin is to glue them together with
aliphatic resin (wood glue). Aliphatic resin sands much
easier than CA so your skins won't get too thin from over
sanding. Wipe off the excess glue with a damp paper
towel. Use masking tape to hold the sheets together
until the glue cures - usually in about thirty minutes.
D 5. Remove the stab from your building board. Inspect
all the glue joints and add CA to any joints that don't look
strong. Cut the ends of the leading and trailing edges so
they extend past the end of the stab about 1/16". Use
your bar sander to finish the job by sanding the ends of
the LE'S and TE so they are flush with the end of the stab.
Use your bar sander or a large sanding block and 220-grit
sandpaper to sand the entire top and bottom surface of
the stab until it is flat and even. Be careful that you don't
sand any area
bracing and ribs by snagging the sandpaper on them.
of
the stab too
thin
or
gouge the stab
cross
D 6. Make the skins for the stab by using five 1/16" x 3" x
30" balsa sheets. Cut one 1/16" x 3" x 30" as shown in the
the top sketch. Make a pair of skins by edge-gluing two
1/16" x 3" x 30" balsa sheets together. Center and glue
the cut sheet on the edge of the glued sheets. Use your
bar sander or a large sanding block and 220-grit
sandpaper to sand the entire top and bottom of the
skin flat.
9
D 7. Place one of the stab skins on your building board.
Apply an even bead of medium or thick CA to one side of
the stab framework. Place the framework in its proper
position on the skin and press it down firmly until the glue
has set. Repeat this step for the other side of
the stab.
D 8. After the glue has cured, remove the stab from the
building board and trim the sheeting close to the
framework. Use a bar sander or large sanding block and
220-grit sandpaper to sand the top and bottom skins flush
with the stab framework. Cut the tips from the 1/2" x 7/8"
x 24" balsa stick. Glue the tips onto the end of the stab
and sand a radius on the corner of the LE.
D D 1. Place a piece of wax paper over the elevator plan.
Cut the 1/2" x 7/8" x 24" balsa stick 3-5/8" long to make
an elevator tip. Pin the elevator tip to the plan, allowing
the tip to overhang by 1/16" at the LE and TE.
D D 6. Make the 1/8" cross bracing from a 1/8" x 1/4" x
30" balsa stick. Note that the cross bracing overlaps. The
bottom bracing should be flush with the bottom of the
elevator and the top bracing should be flush with the top
of the elevator. Glue the cross bracing in position. We
recommend cutting these cross braces with a single-edge
razor blade.
D D 7. Remove the elevator from your building board.
Inspect all the glue joints and add CA to any joints that
don't look strong. Cut the end of the leading edge so that
it extends past the end of the elevator about 1/16". Use
your bar sander to finish the job by sanding the ends of
the LE and elevator tip so they are flush. On the end of
the elevator root, sand a radius to match the plan. Sand
the entire top and bottom surface of the elevator until it is
flat and even. Be careful that you do not sand any
particular area of the elevator too thin or gouge the
elevator cross bracing and ribs by snagging them on
the sandpaper.
D 8. Go back to step 1 and build the second elevator
following the same procedure.
D D 2. Cut a 1/2" x 3/4" x 30" balsa stick in half to make
the elevator leading edge and elevator trailing edge. Use
the plan or a straightedge as a guide to make sure the
elevator LE is straight as you glue and pin it in position.
D D 3. Cut and sand the end of the elevator TE to match
the plan. Again, use the plan or a straightedge as a guide
to make sure the elevator TE is straight as you glue and
pin it in position.
D D 4. From the 3/8" x 1/2" x 30" balsa stick, cut and
glue the elevator root to the LE and TE. Leave an
overhang of 1/16" at the TE. This will be sanded off after
the elevator is removed from the building board.
D D 5. Make the 3/8" elevator ribs from the 3/8" x 1/2" x
30" balsa stick. Then glue them in position. From the 1/2"
x 3" x 3-1/2" balsa block, cut the elevator horn block and
glue it in position.
D 1. Place a piece of wax paper over the fin plan. Cut the
3/8" x 3/4" x 24" balsa stick 13-3/4" long to make a fin TE.
Pin the fin TE to the plan, allowing the TE to overhang the
top by 1/16". Cut the remaining 3/8" x 3/4" balsa stick
9-1/8" long to make a fin TE doubler. Glue the fin TE
doubler to the fin TE so that the top end of the TE doubler
is positioned correctly over the plan and the bottom end
overhangs. Cut the second 3/8" x 3/4" x 24" balsa stick to
make the fin LE. Trim one end of the fin LE to the angle
shown on the plan and allow the other end to overhang
the top slightly. Use the plan or a straightedge as a guide
to make sure the fin TE and LE are straight as you pin
them in position.
10
D 4. Make the skins for the fin by using three 1/16" x 3" x
30" balsa sheets. Cut each sheet in half. Make a skin by
edge gluing three sheets together. Use your bar sander or
large sanding block and 220-grit sandpaper to sand the
entire top and bottom of the skin flat.
D 2. To make the fin tip, cut the remaining short piece of
3/8" x 3/4" balsa stick to fit between the fin LE and TE.
When satisfied with the fit, glue the fin tip to the LE and
TE. Cut the 3/8" x 3" x 14-7/8" balsa block to make the fin
LE brace and fin bottom. Cut two notches in the fin
bottom for the #8x1" screws that secure the stabilizer to
the fuselage. Glue and pin them in position.
D 5. Pin one of the fin skins down on the building board.
Apply an even bead of medium or thick CA to one side of
the fin framework. Place the framework in its proper
position on the skin so that the LE of the fin is flush with
the edge of the 15" balsa sheet and press it down firmly
until the glue has cured. Repeat this step for the other
side of the fin. Do not apply the 1/16" skin to the fin post.
D 6. After the glue has cured, remove the fin from the
building board. Use your bar sander or a large sanding
block and 220-grit sandpaper to sand the edges of the top
and bottom skins flush with the fin framework.
D 1. Place a piece of wax paper over the rudder plan. Cut
the 1/2" x 3/4" x 30" balsa stick 14" long to make a rudder
LE. Cut the remaining 1/2" x 3/4" balsa stick 12-3/4" long
to make a rudder TE. Pin the rudder LE and TE to the
plan, allowing the ends to overhang the top and bottom of
the rudder by 1/16". Use the plan or a straightedge as a
guide to make sure the rudder TE and LE are straight as
you pin them in position.
D 3. From the 3/8" x 1/2" x 30" balsa stick, make the fin
ribs. Then glue them in position. Remove the fin from
your building board. Inspect all the glue joints and add CA
to any joints that don't look strong. Use your bar sander to
sand the top of the LE and TE so they are flush with the
fin tip. Sand a radius on the end of the LE to match the
plan. Sand the entire top and bottom surface of the fin
until it is flat and even. Be careful that you do not sand
any particular area of the fin too thin or gouge the fin
cross bracing and ribs by snagging them on the
sandpaper.
D 2. Make the rudder tip by cutting the remaining short
piece of 1/2" x 7/8" balsa stick to fit between the rudder
LE and TE. When satisfied with the fit, glue the rudder tip
to the LE and TE. Cut the 1/2" x 3" x 3-1/2" balsa block to
make the rudder bottom. Glue and pin the rudder bottom
in position.
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D 3. Make the rudder ribs from the 3/8" x 1/2" x 30"
balsa stick, then glue them in position. Make the 1/8"
cross bracing from a 1/8" x 1/4" x 30" balsa stick. Note
that the cross bracing overlaps the same as on the
elevator. Glue the cross bracing 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. Use your bar sander to sand the ends of the LE
and TE so they are flush with the rudder tip and rudder
bottom. Sand a radius on the TE and rudder bottom to
match the plan. Sand the entire top and bottom surface of
the rudder until it is flat and even.
Hinge The Tail Surfaces
C. Use playing cards or business cards to adjust the
height of the pen until you can mark the centerline. Mark
the hinge centerline at each hinge location.
D. Use the same technique to mark the centerline along
the entire length of both elevators.
D 1. Place the stab and elevator over their locations on
the plan and lightly mark the hinge locations on the TE
of the stab and LE of the elevator with a ballpoint pen.
D 2. Refer to the Expert Tip that follows. Then mark the
centerline of the hinges on the stab and elevators.
How to mark hinge slots
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. We'll start with
the stabilizer.
D 3. If using a flat type hinge, cut the hinge slots in the
elevator and stab using a #11 blade. Begin by carefully
cutting a shallow slit at the 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. Lay the stabilizer and a ballpoint pen on a flat
surface. Mark a "test line" on the trailing edge of the
stab away from the hinge locations you marked earlier.
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 hinge centerline at each
hinge location. If you see two lines you will have to
adjust the height of the pen until you can mark
the centerline.
D 4. Follow the same procedures to hinge the rudder and fin.
D 1. Refer to the Expert Tip that follows and shape the
leading edge of the elevators to a "V" as shown on the plans.
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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 3/16" high.
Note: You will probably have to adjust the height of the
elevator with card stock (as you did while marking the
hinge slots) so your "bevel to" line is not too high making too sharp of a "V".
D. 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 loaded with 150-grit
sandpaper.
D 2. Use the same procedure to bevel the leading edge
of the rudder.
D 1. Use 30-minute epoxy to glue the four forward and
four aft die-cut 1/16" ply rib doublers to both sides of the
two die-cut 1/8" balsa R-PB ribs. Take extra care to not
get epoxy in the slots for the strut tabs.
D 2. Use 30-minute epoxy to glue the sixteen die-cut
1/16" ply strut tabs together to make eight pairs. Note:
The die-cut 1/16" ply strut tabs have been cut with the
wood grain running in opposite directions. Glue together
one of each to make 1/8" plywood strut tabs. Also make
sure that the punch marks can be seen.
D 3. After the epoxy has cured, drill a 1/16" hole through
the strut tabs, at each of the punch marks.
Start by building the bottom right wing panel right side up
over the right wing panel plan. Match together sets of
spars so any warps will counteract each other.
D 3. Draw a centerline on the stab LE, stab tips, elevator
tips, elevator TE'S, fin LE, fin tip, rudder tip and rudder TE.
Use you bar sander and 150-grit sandpaper to round the
edges as shown on the plan. Use the centerline as a
guide to keep the radius symmetrical. Do not round the
TE of the stab.
TWO WARPED SPARS INSTALLED
THIS WAY WILL RESULT IN A
STRAIGHT WING
RIGHT
TWO WARPED SPARS INSTALLED
THIS WAY WILL RESULT IN A
WARPED WING
WRONG
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D D 1. Cover the bottom right wing plan with wax paper.
Then use the cross-pinning technique (see sketch above)
to pin a 3/16" x 1/2" x 36" hardwood main bottom spar
over the wing plan. The spar should be flush with the
outside face of rib R-6.
D D 2. Place the die-cut wing ribs R-1B, R-2B, R-5, R-
5A, R-5B, R-PB and R-6 on the top of the spar, over their
locations on the plan.
D D 5. Position the 36" shaped balsa leading edge (LE)
on the front of the ribs. The LE should be centered on all
ribs and the tip end should extend past rib R-6 by at least
1-5/8". Make sure all the jig tabs are contacting the
building board, then use thin CA to glue the LE to the front
of the ribs.
Note: While the jig tabs should be contacting the plan,
you should check rib alignment with a straightedge. Shim
the forward or aft jig tabs with paper to raise any ribs that
are low. Use small T-pins to pin the forward and aft jig
tabs to the building board over their location on the plan.
On the aft jig tabs, insert the T-pins at an angle from the
rear so they can be removed after the TE and sheet is
glued in position.
D D 3. Place the 3/16" x 1/2" x 36" hardwood main top
spar in the notches of the ribs. The end of the spar should
be flush with the outside face of rib R-6 and with the top of
the ribs. With the ribs perpendicular to the building board,
glue the ribs to the top and bottom spars with thin CA.
D D 4. Insert the 1/4" x 1/4" x 36" balsa aft spars in the
notches in the aft end of the ribs. The end of the spar
should be flush with the outside face of rib R-6 and with
the edges of the ribs. As you are gluing the spars to the
ribs with thin CA, check that the ribs are perpendicular
to the building board and the jig tabs are against the
building board. (See note above.)
D D 6. Cut the 36" balsa trailing edge (TE) 17" long.
Use thin CA, to glue the TE to the ends of ribs R-1B, R-2B
and R-5.
D D 7. From the 3/32" x 3" x 24" balsa sheets, make
shear webs to fit on the front of the main spar starting at
rib R-2B to R-6, behind the main spar from rib R-2B to
R-5B and to the front of the aft spar from rib R-2B to the
aileron bay. The grain of the shear webs runs
perpendicular to the spars and the shear webs must be
glued securely to the spars.
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D D 8 Use medium CA to glue the die-cut 1/8" balsa
gusset to rib R-5 and the shear web Sand the TE flush
with rib R-5 Then glue the die-cut 1/8" balsa rib caps to
ribs R-5 and R-6.
D D 1 Fit a 3/32" x 3" x 36" balsa sheet to the top of the
wing panel by first sanding a bevel on the front edge of
the sheet to match the angle of the leading edge of the
wing Before you glue the LE sheet in position, remove
the T-pins from the front jig tabs Reinstall the T-pins
through the ribs right behind the bottom main spar
D D 3 Wet the sheet once more Carefully lift the sheet
away from the ribs Then apply a bead of medium or thick
CA to the top of each rib Working quickly, pull the sheet
back toward the main spar as you press it down to the
ribs and spar Glue the aft edge of the sheeting to the
main spar with thin CA Use masking tape T-pins or
weights to hold the sheet to the ribs until the CA cures
Note: Save all leftover 3/32" sheeting for use on the
fuselage.
D D 2 Wet the outside of the LE sheet so it will bend
more easily Hint: A 50/50 mix of water and either alcohol
or ammonia helps soften the wood fibers so the sheet is
even easier to bend Position the front of the sheet
against the LE and flush with the side of rib R-6 Glue it in
position with thin CA.
D D 4 Lightly sand the TE area so that the TE and aft
balsa spar are flush with the top of the ribs From a 3/32"
x 3" x 36" balsa sheet, cut a TE sheet 17-1/4" long Save
the cut off piece for the bottom TE Glue the sheet to the
TE and ribs so that it overhangs the balsa rib cap, at rib
R-5, by 1/32" and is flush with the front edge of the aft
balsa spar Do not trim the sheet at the TE.
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D D 5. Glue a 3/32" x 3/8" x 30" balsa cap strip on the
top of rib R-6. The cap strip should be flush with the
outside of the rib and extend past the TE by 1/2". Use the
leftover cap strip to cover the aft balsa spar from rib R-5
to R-6. The cap strip should be flush with the front of the
aft balsa spar.
D D 6. To locate the slot for the strut tab in rib R-PB,
place a mark 1/2" and 1-1/2" from the aft edge of the top
main spar. Use the side of rib R-PB as a guide to mark
the sides of the slot. Using a sharp hobby knife, trim the
LE sheet from over the slot.
D D 8. From the 3/32" x 3/8" x 30" balsa sticks, cut cap
strips. Use medium CA to glue them to the tops of the
ribs. Be sure to cut an opening for the strut slot in the cap
strip on rib R-PB.
D D 9. Remove the T-pins and take the wing off your
building board. Carefully remove the jig tabs. Using a
sanding bar with 150-grit sandpaper, sand the ribs flush
with the bottom main spar and aft balsa spar. Sand the TE
sheet aft of the TE to match the angle of the TE and ribs.
D D 1. Use a razor saw and sanding bar to accurately cut
the spars, LE, TE and top sheet flush with rib R-1B.
D D 7. Use a 3/32" x 3" x 30" balsa sheet to make the
center sheeting between the LE sheet and the TE sheet.
Before you glue the center sheeting in position, remove
the T-pins from ribs R-1B, R-2B and R-5.
D D 2. On rib R-1B use a straightedge to draw lines
connecting the front of the aft balsa spars, and the corner
of the notch in front of the aft balsa spar. Also, draw lines
connecting the front and aft corners of the top and bottom
main spars. Then draw lines continuing the sides of the
die-cut rectangle. Use a razor saw to cut slots
in front of the aft balsa spar and in front and behind the
main spar.
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