Great Planes GPMA0540 User Manual
INSTRUCTIONS
READ THROUGH THIS INSTRUCTION BOOKLET IN ITS ENTIRETY BEFORE BEGINNING ASSEMBLY.
IT CONTAINS IMPORTANT INSTRUCTIONS AND WARNINGS CONCERNING THE BUILDING AND USE OF
THIS MODEL.
WARNING! THIS IS NOT A TOY!
The model you will build from this kit is not a toy! It is capable of serious bodily harm and property
damage. IT IS YOUR RESPONSIBILITY AND YOURS ALONE -- to build this kit correctly,
properly install all R/C components and to test the model and fly it only with experienced, competent
help, using common sense and in accordance with all safety standards as set down in the Academy of
Model Aeronautics Safety Code. It is suggested that you join the AMA and become properly insured
before you attempt to fly this model. IF YOU ARE JUST STARTING R/C MODELING,
CONSULT YOUR LOCAL HOBBY SHOP OR WRITE TO THE ACADEMY OF MODEL
AERONAUTICS TO FIND AN EXPERIENCED INSTRUCTOR IN YOUR AREA.
Academy of Model Aeronautics
5151 East Memorial Drive
Muncie, IN 47302-9252
PO BOX 788 Urbana Illinois 61801 217/3988970
TABLE OF CONTENTS
Die Patterns
INTRODUCTION
Precautions
Other Items Required
Optional Hop-up Items
Supplies and Tools Needed
A
Word
Abbreviations
Types of
Get Ready to Build
TAIL FEATHERS
Build the Fin and Rudder
Build the Stabilizer and Elevator
Cut the Hinge Slots
WING ASSEMBLY
A Decision
Build the Inner Wing Panel
Build the Outer Wing Panel
....................3
...............4
..................... 4 Checking for Warps
............. 4 Glue the Hinges
............ 5 Mount the
......... 5 Assemble Pushrods
About Adhesives
................... 6 Control Throws
Wood
................... 6 Final Hookups and Checks
............... 6 Balance
............... 8 Range Check
You
Should Make Now
........... 5 Install Radio Gear
...............6
........... 6 Charge the Batteries
..............9
......... 9 General
.........
Final Sanding
Covering
Your
PRE-FLIGHT
..... 7 Find a Safe Place to Fly
Install the Wings
... 9 AMA Safety Code
........................
13 Radio Control
...................
.......................
..............
.................
Tail
Surfaces
...............
................
..................
Model
Your
...................
..............
..................
..............
Radio
.................
...............
...........
.........
...........
..........
25
25
26
26
26
27
27
30
30
31
31
31
31
32
32
32
32
32
Join the Inner and Outer Wing Panels . 15 FLYING
Final Wing Assembly
FUSELAGE ASSEMBLY
Assemble Fuselage Sides ........... 19 THERMAL FLYING
Frame-up the Fuselage
Assemble the Canopy
Install the Motor
FINAL ASSEMBLY
Balance the Airplane Laterally
..............
.........19
.............
.............
.................
.............
.......
16 Hand Launched Trim Flights
Your
20
Facts About Thermals
22
Thermal Soaring
24 Some Important Soaring Tips
25
Dynamic Braking Modification
25 PARTS LIST
.......................
First Flight
.................
............
.............
.................
...................
........
.......
......
32
32
33
34
34
34
35
35
36
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 (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.
2
DIE PATTERNS
Do not punch out die-cut parts until you are ready to use them!
SPECFOl
SPECF06 1 PER KIT
BALSA 1/8 X 3 X 8 7/8
SPRTW07 2 PER KIT
BALSA 1/16 X 3 X 15
I
PER
SPECF05
KIT
2
PER
BALSA 3/32 X 3 1/4 X 38 1/2
SPECF02 2 PER KIT
BALSA 1/16 X 3 1/4 X 23 7/8
SPECF03 1 PER KIT
PLY
1/8 X 3 X 19
SPRTF04
1
PER
KIT
KIT
SPECF13
BALSA 1/16 X 2 5/8 X II 7/6
SPECF07 1 PER KIT
PLY
1/8 X 2
SPRTS01 I PER KIT
BALSA
SPRTW08
SPRTW05
7/8 X 7
3/16" X 3" X 9-7/8"
PLY
1/8 X 3
NOT
7/8 X II
USE0IN SPECW<
7/8
K
T I PER
2 PER
I
PER
7/8
KIT
KIT
KIT
BALSA 3/32 X 4 X 21
SPRTW02 2 PER KIT
BALSA 1/16 X 3 X 23 7/8
SPRTW03 2 PER KIT
BALSA 1/16 X 3 X 23 7/8
I
PER
SPRTW01
BALSA 1/8 X 3 X 23 7/8
SPRTW04 1 PER KIT
SPRTW06 I PER KIT
KIT
PLY
1/16 X 3
3/8 X II
7/8
PL Y 1/8 X 3
3/4 X 10
3
1/2
PL Y 1/32 X 3
1/4 X 9
3/4
INTRODUCTION
Congratulations! You are about to enter one of the most
exciting realms of radio control flying - Electric Powered
Sailplanes.
Electric powered soaring is one of the most enjoyable
types of R/C flying because it combines the convenience of
being able to fly from almost any small field with the
challenge of staying aloft for long periods of time. There is
something very gratifying about defying gravity and being
able to gain altitude using only nature's own air currents. The
Spectra's powerful Goldfire motor quickly pulls it up to
thermaling altitude where the motor is shut off and the
Spectra becomes a "Thermaling Machine". With a little
practice, you will be able to soar for hours in a single flight!
We would like to take this chance to thank you for
purchasing the Great Planes SPECTRA Electric Sailplane. It
has been designed to give you many hours of enjoyable flight,
and we spent many months engineering it to be a very
enjoyable kit to build. If you have any comments or suggestions feel free to share them with us.
PRECAUTIONS
1. You must build the plane according to the plans and
instructions. Do not alter or modify the model as doing so
may result in an unsafe or un-flyable model. In a few cases
the plans and instructions may differ slightly from the photos.
In those instances you should assume the plans and written
instructions are correct
2. You must take time to build straight, true and strong.
Note: We, as the kit manufacturer, can provide you with a top
quality kit and great instructions, but ultimately the quality
and'' fly-ability "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.
OTHER ITEMS REQUIRED
RADIO - A Radio having at least 2 channels is required to
control the SPECTRA (a third channel is required for throttle
control). Standard size servos can be used without any
problem but a 250 mAh receiver battery is recommended but
not required. Make sure that the radio is on an "Aircraft
Only'' frequency.
FLIGHT BATTERY - A 6 or 7 cell battery with a " Kyosho"
type connector is required to power the electric motor. We
recommend you use a 7 cell battery as it offers much higher
performance than a 6 cell battery. The capacity (mAh) of the
battery can be anywhere from 800 mAh to 1700 mAh. For
general flying a 1200 -1700 mAh 7 cell battery will provide
good power, good motor duration, and good flight performance. For contest flying an 800 - 900 mAh 7 cell battery will
provide a shorter motor duration but its lighter weight will
enable the SPECTRA to climb quicker and soar better. A
1200 -1700 mAh 6 cell battery should be used if you just want
to fly around with the motor on continuously. If your batteries
have "Tamiya" style connectors, you'll have to change the
connector on the wiring harness, or purchase a Kyosho #6195
adaptor.
3. You must use a proper R/C radio that is in first class
condition.
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 the first
and each successive flight to insure that all equipment is
operating, and you must make certain that the model has
remained structurally sound. Be sure to check the nylon
clevises often, and replace if they show signs of wear.
6. You must fly the model only with the competent help of
a well experienced R/C pilot if you are not already an
experienced and knowledgeable R/C pilot at this time.
CHARGER - A quick (15-20 Minute) charger is required to
charge your flight battery. These chargers come in many
different styles (DC, AC/DC, Timed, Peak, Temperature
Sensing, etc.).
The most inexpensive charger will be a DC Quick
Charger with a 15 - 30 minute timer. This type of charger will
work fine but you should never leave the charger unattended
while charging as the timers are not always reliable. If the
timer sticks or the battery already had some charge in it, the
battery could be over charged, heat up and explode. If you use
this type of charger, check the temperature of the battery
every couple of minutes and turn the charger off as soon as the
battery starts getting warm.
The best type of chargers are the "Peak'' chargers. They
constantly measure the voltage of the battery being charged
and when the voltage starts to drop (as the voltage of a Nicad
battery will do when it is fully charged) it will shut off. All
4
you have to do is connect the battery, push one button and
come back when its done.
OTHER ITEMS:
Iron-on Covering Material-2 rolls (we recommend Monokote
for the wing because of its superior strength)
Latex Foam Rubber Padding (1/4" thick)
#64 Rubber Bands
OPTIONAL HOP-UP ITEMS:
FOLDING PROP - A folding prop can be used instead of the
8x4 nylon prop supplied. It will fold back against the
fuselage when the motor is not running and enhance the
soaring performance of the plane. Sonictronics makes several nice folding props and we have found the model #174
8x4 folding prop to work well on the SPECTRA with the
GOLDFIRE motor. The spinner may have to be carved out
slightly to clear a folding prop. Because the prop may have
a tendency to keep spinning after the motor is shut off, the
switch/motor should probably be re-wired to provide dynamic braking to the motor. This is easy to do and will make
the motor stop turning so the prop will fold back. There is a
sketch on page 35 showing this wiring modification.
LIGHTWEIGHT RADIO - There are several "Micro Systems" on the market that come with smaller servos, receiver
and batteries. Futaba makes a radio especially for electrics
(model 4NBL Attack E) which works well with the
SPECTRA. It comes with two S-133 Micro Servos and a 4
channel Receiver with a fully proportional electronic speed
control built in. This unit also has BEC (Battery Eliminater
Circuitry). This feature allows the radio system to be powered by the flight battery (6 or 7 cell). It will automatically
shut the motor off before the battery is totally drained, leaving
another 20 minutes or so of flying time in the flight battery.
These smaller radio systems can save several ounces of
valuable weight which will improve both the climbing and
soaring capabilities of the plane.
Your local hobby shop can be very helpful when
deciding what types of accessories to purchase. We highly
recommend that you consult with and support your local
hobby dealer when purchasing the above items. He can
also be a tremendous help if you have problems building
or flying your models.
SUPPLIES AND TOOLS NEEDED
1 oz. Thin CA Adhesive
2 oz. Medium or Thick CA Adhesive (We'll refer to it as
"thick"
2.5 oz. 30-Minute Epoxy
Hand or Electric Drill
Drill Bits: 1/16", 3/32", 1/8", 1/4"
Sealing Iron
Heat Gun
Razor Saw
Hobby Knife, #11 Blades
Pliers
Screw Drivers
T-Pins
Assorted Rubber Bands
Straightedge
Masking Tape
Sandpaper (coarse, medium, fine grit)*
T-Bar Sanding Block (or similar)
Waxed Paper
Lightweight Balsa Filler
Dremel Moto Tool or Similar (optional)
*NOTE: On our workbench, we have four 11" T-Bar sanders,
equipped with #50, #80, #100 and #150-grit sandpaper. This
setup is all that is required for almost any sanding task. We
also keep some #320-grit wet-or-dry sandpaper handy for
finish sanding by hand before covering.
in
the instructions)
A WORD ABOUT ADHESIVES
COBALT MOTORS - A GOLDFIRE motor is included in
this kit. It is a 550 size motor designed especially for
airplanes. It is an inexpensive motor that is as powerful as
many motors costing 3 times as much. We do not recommend
that you use any of the 540 size "Car'' motors. Their smaller
size and higher RPM requirements do not work well when
trying to turn a propeller at 12,000 rpm. If you want a higher
performance motor, we recommend you use an Astro Fight
.05 Cobalt Motor (Model 6605 or 6605 S). These motors are
very powerful and will make your SPECTRA climb like
crazy with some sacrifice in run time. We recommend that
you use either Sermos Power Pole Connectors or Deans Connectors on the battery and motor when using high performance motors. These connectors have a very low resistance
and will carry the larger currents better than the more popular
connectors provided.
If you looked at the "ITEMS NEEDED" list above, you
probably noticed that we recommend only two basic types of
glue for assembling the SPECTRA. . .CA adhesives and
Epoxy adhesive. Glues have come a long way in the past few
years and these two types of adhesive are all that is needed to
build a strong and light structure.
CA (Cyanoacrylate) - These are the "Super Glues". They
have revolutionized model building by eliminating the "wait
for the glue to dry'' phase of building. CA'S will be used for
95% of the building. They come in several viscosities but we
will only require the "Thin" (Runs like water) and the
"Medium" (Like a thin syrup). The thin CA will be used
where there is a nice tight fitting joint. It is applied after the
5
parts are in position and it seeps into the joint through
capillary action and bonds the parts within a couple of
seconds. The thicker CA is applied to the parts before they are
joined and it takes up to 30 seconds to cure giving you a few
seconds to position the parts. A related and very handy
product is CA Accelerator Spray (Zip Kicker, etc.). This is
used to instantly cure CA glues of all types.
EPOXY - Epoxy adhesives are two-part resins that are very
strong but need to be mixed before they will cure. This
process along with their heavier weight does not lend itself
well to general construction. Epoxies are used where the
utmost in strength is required. They come in many different
cure times but we will only need 30 minute epoxy.
AN IMPORTANT TIP - Glue should never be
substituted for a good-fitting joint. Take a little
extra time to get a good joint and glue it properly and
it will be much stronger, much neater and much
lighter than a bad joint held together with a glob of
glue!
COMMON ABBREVIATIONS USED IN
THIS BOOK AND ON THE PLANS:
GET READY TO BUILD
NOTE: It will be helpful to build on a piece of "Celotex"
(available from a lumber co.) or other semi-soft (and flat) surface, into which you may easily suck pins to firmly hold down
the parts while building, and to avoid warps.
1. Unroll the plan sheet. Re-roll the plan inside out and let
it uncurl while you read through this instruction book. This
will help the plan lay flat and give you time to get acquainted
with the building process. NOTE: Because there are
several options to consider when building the SPECTRA,
you should read the instruction book through before
building and then go back and cross off the steps you won't
use to build your model.
2. Remove all parts from the box. As you do, figure out the
name of each part by comparing it with the plans, the die
patterns (p. 3) and the parts list at the back of this book. Write
the part name or size on each piece to avoid confusion later.
If any of the die-cut parts are difficult to punch out during
construction, do not force them! Instead, first cut around the
parts with a hobby knife. After punching out the die-cut parts,
use your T-Bar or sanding block to lightly sand the edges to
remove any die-cutting irregularities.
Elev = Elevator
Fuse = Fuselage
LE = Leading Edge (front)
Lt = Left
Ply = Plywood
Rt = Right
Stab = Stabilizer
TE = Trailing Edge (rear)
Tri = Triangle
" = Inches
TYPES OF WOOD
NOTICE: INSTRUCTIONS IN BOXES ARE VERY
IMPORTANT AND SHOULD BE FOLLOWED CARE-
FULLY.
"TAIL FEATHERS"
BUILD THE FIN AND RUDDER
You'll need the following parts:
SPRTS02 3/16" x 3/8" x 30" Balsa Stick
SPRTS03 1/8" x 3/16" x 30" Balsa Stick
SPRTS01 3/16" Die-Cut Balsa Tail Parts
SPECF08 3/16" Balsa Triangle
BALSA BASSWOOD PLYWOOD
D 1. Tape or pin the plan down to your flat work surface.
Tape a piece of waxed paper over the fin and rudder portion
of the plan (so you don't glue the parts to the plan).
6
D 2. Using the plan as a guide, cut pieces of 3/16" x 3/8"
balsa (from the 30" sticks, SPRTS02) to make the Rudder
and Fin Framework. NOTE: Cut the Fin L.E, the Rudder
L.E. and the Rudder T.E. from a single SPRTS02 (this will
leave enough long pieces for the stab frame). Punch out the
die-cut Fin Tip, Rudder Tip, Fin Base and Rudder Base
from SPRTS01. Sand any rough edges on these pieces and
then pin them in place on the plan. Glue the parts together
using thin CA glue. CAUTION: Do not glue the fin to the
rudder!
D 3. From the 1/8" x 3/16" x 30" sticks (SPRTS03), cut
the diagonal "ribs" to fit between the rudder and fin framework, and glue them in place. NOTE: It is not necessary to
get these ribs in the exact position shown on the plan.
D 5. Carefully draw a centerline all around the edges of
the rudder (this will help to maintain symmetry when sanding).
D 6. Cut 4-1/8" off of the 3/16" Balsa Triangle (SPECF08)
and glue them along the bottom of the fin. The bottom edges
of the triangle should be flush with the bottom of the fin.
D 7. Using a sanding block and coarse (50 or 80-grit)
sandpaper, sand the leading edge of the rudder to the V-shape
as shown on the plans (a small razor plane works great for
initial shaping). Sand the three remaining edges to a smooth
rounded shape. Sand the top and the leading edge of the fin
to a nice rounded shape*. NOTE: The trailing edge of the
FIN must remain square, do not round it! Sand the triangle
stock to blend with the leading and trailing edges of the fin.
Also, cut or sand the bottom of the triangle stock to match the
contour of the 3/16" die-cut fin bottom.
D 4. Remove the fin and rudder assemblies from the plan
and examine them for any open or bad joints. Fill any gaps
with thick CA, then use your sanding block with medium grit
sandpaper to sand both sides of the framework smooth.
* MAXIMUM PERFORMANCE TIP - Sand both sides of
the rudder to a taper as shown on the plans. This requires a
little more work but will help to reduce drag and thus increase
performance of the sailplane.
BUILD THE STABILIZER AND ELEVATOR
You'll need the following parts:
SPRTS02 3/16" x 3/8" x 30" Balsa Sticks
SPRTS03 1/8" x 3/16" x 30" Balsa Slicks
SPRTS01 3/16" Die-Cut Tail Parts
SPRTS04 Tapered Elevator
7
D 1. Tape waxed paper over the stabilizer drawing on
the plan so you don't glue the parts to the plan. Using the plan
as a guide, cut the 3/16" x 3/8" balsa pieces from SPRTS02.
Punch out the die-cut Stab Tips, Stab Center and Stab
Brace from SPRTS01 and sand the edges if necessary to
remove any "fuzz''. Assemble the stab framework by pinning
everything in place on the plan. Glue the parts together using
thin CA glue.
D 2. Cut and sand the 1/8" x 3/16" "ribs" (from
SPRTS03) to length and glue them in place. NOTE: It is not
necessary to get these ribs in the exact position shown on the
plan.
D 5. Tape the elevator to the stab using masking tape and
sand the leading edge of the stab, the stab tips and the elevator
tips to a smooth rounded shape. The tips of the elevator
should blend in nicely with the stab tips.
D 6. Remove the elevator and draw a center line down its
leading edge. Use your sanding block to sand the same Vshape as you did on the rudder. The trailing edge should also
be sanded to a smooth rounded shape. Apply thin CA the the
tips of the elevator to harden the wood, and help protect it
from damage.
CUT THE HINGE SLOTS (Do not glue)
D 3. Pin or tape the elevator (SPRTS04) in place behind
the stab and use your razor saw to cut the ends off to match the
stab. Sand the the two front comers of the stab to round them
off.
NOTE: One-piece molded polypropylene hinges are supplied
in this kit. We have tested many different hinges and have
found that these hinges are one of the best available. We
recommend that you use these hinges and follow the instructions
below to install them. If you choose to use these hinges or the
"pinned"-type hinges, you should cut the hinge slots at this
time. However, if you choose to use the one-piece hinges that
are paper covered for CA glue installation, you may wait until
after covering before cutting the hinge slots.
D 4. Remove the stab from the plan and examine it for
any open or bad joints. Fill any gaps with thick CA, then use
your sanding block with medium grit sandpaper to sand both
sides smooth. Carefully draw a centerline around the edges
of the stab (this will help maintain symmetry when sanding).
D 1. Lay the rudder and elevators on the plan and mark
the hinge locations. Place the rudder against the fin TE and
transfer the marks over to the fin. Place the elevator against
the stab TE and transfer the marks over to the stab.
8
CAUTION!!!: You must use extreme care when
cutting hinge slots with a hobby knife, to avoid
cutting yourself! If the balsa part breaks while
you are pushing on the knife, the blade could go
into your hand before you know it! A good
precaution is to wear leather gloves while
performing the following steps.
WING ASSEMBLY
A DECISION YOU SHOULD MAKE NOW...
"WING CONFIGURATION"
D 2. Draw accurate centerlines down the trailing edge of
the stab and the fin. Cut the hinge slots on these lines using
a hobby knife or a slotting fork and slotting hook. (The
recommended hinge slotting technique is listed below).
A. Begin by carefully cutting a very shallow slit at
the hinge location. This first cut is to establish your cut
in the right place, so concentrate on staying on the
centerline and don't cut too deep!
B. Make three or four more cuts in the same line,
going slightly deeper each time. As you make these
additional cuts, work on going straight into the wood.
Continue this process while "wiggling" the knife handle
forward and backward until the blade has reached the
proper depth for the hinge.
C. Trial fit the hinge into the slot. If the hinge is
difficult to push in, re-insert the knife and move it back
and forth in the slot a few times to enlarge the slot.
D 3. IMPORTANT! Condition or "break-in" the hinges
by folding them back and forth several times.
The SPECTRA kit has two different wing options: a twopiece wing or a one-piece wing. The two-piece wing is the
standard way to build the wing and it is much easier to
transport. The instructions also explain how to build the wing
in one piece which makes it a little stronger but makes it
harder to transport in today's small cars
BUILD THE INNER WING PANELS
You'll need the following parts:
SPRTW01 1/8" Die-Cut Balsa Wing Ribs
SPRTW02 1/16" Die-Cut Balsa Wing Ribs, W2. W2S
SPRTW03 1/16" Die-Cut Balsa Wing Ribs, W2, W4-
W10
SPRTW04 1/8" Die-Cut Plywood Dihedral Braces
SPRTW07 1/16" Die-Cut Balsa Shear Webs
SPRTW08 1/8" Die-Cut Plywood Clamps and Gauges
SPRTW10 Shaped Balsa Leading Edge
SPRTW 11 Shaped, Notched Balsa Inner Trailing Edge
SPRTW13 1/8" x 5/16" x 23-1/2" Basswood Spars
SPRTW17 1/16" x 3" x 24" Balsa Wing Sheeting
D 4. Insert the hinges into the slots and trial fit the rudder
and elevator in place on the fin and stab. Do not glue the
hinges until after you have covered the model. The photo
for this step is at the top of the next column.
NOTE: The wing is designed to be built as a two-piece wing;
however, we also describe how to build a one-piece wing.
D 1. Tape the plan to your flat work surface, and cover
the wing drawing with waxed paper. NOTE: If your work
space is limited, you may cut the wing drawings apart from
the rest of the plans.
D 2. The Shaped Wing Leading Edges (SPRTW10) are
fastened together by thin strips of balsa. Separate them by
carefully cutting between the LE'S. Sand away the excess
balsa that remains along the edges after cutting them apart,
using a sanding block with 100-grit sandpaper. Be careful
when cutting and sanding to follow the contour of the LE'S
and don't sand any more than necessary, otherwise they
may not match up with the ribs and sheeting.
D 3. Before using the 1/8" x 5/16" x 23-1/2" Basswood
Spars (SPRTW13), examine them carefully for possible
imperfections. Look for knots, soft spots, diagonal grain and
any other imperfections. If possible, position each spar so the
imperfections are on the outer half of the wing panel (toward
the tip), where they will be least affected by high stress. If the
spars are warped slightly, "balance them out" by installing
the warped spars in opposite directions (see sketch).
TWO WARPED SPARS INSTALLED
THIS WAY WILL RESULT IN A
STRAIGHT WING
NOTE: The spars may be cut slightly too long. The excess
will be cut off later.
T-Pins
Work Surface
DD 7. Place the seven W-2 ribs (from SPRTW02 and
SPRTW03) and the two W-2S ribs (from SPRTW02) on the
spar in their approximate positions, work the ribs into the
notches on the trailing edge but do not glue anything yet.
Spar
TWO WARPED SPARS INSTALLED
THIS WAY WILL RESULT IN A
WARPED WING
D 4. Carefully punch out all the die-cut 1/16" Balsa W2
and W2S Wing Ribs. Sand the edges slightly to remove any
die-cutting irregularities. The W2S ribs have a die-cut notch
to clear the spoilers in the SPIRIT kit and are not used in this
kit so just treat them like a W2 rib and do not punch out the
notch.
NOTE: Begin building the LEFT wing panel, starting at
step 5 on page 10. Continue through step 8 on page 15.
Next, repeat these steps to build the right wing panel.
DD 5. Pin one of the notched balsa Inner Trailing
Edges (SPRTW 11) to the plan lining up the notches in the TE
with the notches on the plan. Notice that the notches near W3
are only 1/16" wide since half of the 1/8" wide rib notch is in
the inner T.E. and the other half is in the outer T.E..
DD 8. Punch out the two Rib Gauge Pieces from the
1/8" die-cut plywood sheet (SPRTW08) and assemble them
using CA. Notice that one end of the gauge is slanted at a 5
degree angle for positioning the end ribs. The other 3 ends are
perpendicular and can be used to keep parts 90 degrees to the
work surface.
DD 6. Place one of the 1/8" x 5/16" x 23-1/2" Basswood
Inner Spars (SPRTW13) on the wing plan and pin the spar
down with crossed T-pins as shown in the following sketch.
DD 9. Make sure the ribs are properly positioned accord-
ing to the plans and glue them in place using thick CA at the
spar joint and a drop of thin CA at the trailing edge joint. Use
10
the square end of the rib gauge to keep the ribs perpendicular
to the work surface.
DD 10. Trial fit the top 1/8" x 5/16" x 23-1/2" Basswood
Inner Spar (SPRTW13) into the notches in the ribs by
carefully pushing the spar completely down into the notches.
Make sure the top spar is lined up lengthwise with the bottom
spar. Remove the spar and glue it in place by applying thick
CA to the notches before the spar is put back in place.
DD 12. Locate the 1/16" Balsa Die-Cut Shear Web
Sheet (SPRTW07) and notice that all of the shear webs are
not the same. The webs between the stamped number 2's are
for use on the inner panel. The webs between the 2 and the 10
are for the outer panel and each one of these is a different size
so keep them in the sheet until they are ready to be used.
Punch out all of the "2" shear webs.
DD 13. Trial fit one of the webs in place between the first
two W-2 ribs. You may have to sand it slightly to get it to fit.
Glue the shear web in place on the back of the spars using
thick CA. The webs should be centered between the spars. It
is important to do a good job of gluing these in place as they
are responsible for most of the wing's strength. C-2 Clamps
from the 1/8" Die-Cut Plywood Sheet (SPRTW08) can be
used to help hold the webs in place while the glue cures.
DD 11. Position a Pre-shaped Leading Edge (SPRTW 10)
in place over the plans. NOTE: These leading edges are
NOT symmetrical. Refer to the wing end view on the plan
to determine which way they should be installed. Carefully
hold the leading edge against one of the end W-2 ribs and note
that it is wider than the front of the rib. This is because the 1/
16" balsa leading edge top sheeting will be added later. Align
the lower surface of the leading edge with the bottom of the
rib and glue it in place with a drop of thin CA (there must be
a 1/16" gap between the top of the rib and the top of the LE
so the sheeting will fit). Lift up the other end of the leading
edge, align it with the bottom of the opposite end W-2 and
glue it with a drop of thin CA. Go down the line and glue the
remaining ribs to the leading edge one at a time so you can
make sure they are aligned. CA Accelerator may come in
handy for speeding up this process if you don't want to hold
the LE in place long enough for the glue to cure naturally.
DD 14. Install the remaining balsa shear webs. Note that
the webs are only installed between the ribs already glued in
place. Three webs are also installed on the front of the spars
in the first three rib "bays". Remove the T-Pins as the webs
are installed but make sure the panel is kept flat throughout
this process.
IF YOU ARE BUILDING A ONE-PIECE WING, SKIP
AHEAD TO "BUILD THE OUTER WING PANELS"
ON PAGE 13. STEPS 15 THROUGH 23 ARE FOR A 2PIECE WING ONLY.
DD 15. Locate the 1/8" die-cut sheet (SPRTW04) that
contains the Dihedral Braces, the Leading Edge Brace and
the Wing Joiner Lamination. Line a ruler up with the two
embossed cut marks and draw a line across both of the
dihedral braces.
DD 16. Punch out the two dihedral braces and cut them in
half with a razor saw along the lines you just drew. Note:
these braces are supplied in one-piece for the one piece
option. Also punch out the wing joiner lamination from that
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