Great Planes GPMA0410 User Manual
ULTRA-SPORT 40
INSTRUCTION BOOK
PLEASE READ THROUGH THIS INSTRUCTION BOOKLET IN ITS ENTIRETY BEFORE BEGINNING ASSEMBLY. IT CONTAINS IMPORTANT INSTRUCTIONS AND WARNINGS CONCERNING THE
ASSEMBLY AND USE OF THIS MODEL.
WARNING! THIS IS NOT A TOY!
This R/C kit and the model you will build 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 flying gear (engine, tank, pushrods, etc.) and to test
the model and fly it only with experienced, competent help in accordance with all safety standards and
common sense as set down in the Academy of Model Aeronautics Safety Code. It is suggested that you
join the AMA to 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
1810 Samuel Morse Dr.
Reston.VA 22090 (703)435-0750
POBOXW
URBANA
ILLINOlS 61601 36720t9
TABLE OF CONTENTS
INTRODUCTION .............. 3
Precautions
Abbreviations
Decisions
Other Items Required
Die Patterns
Supplies and Tools Needed
Types
GET READY TO BUILD
Tail
Feathers
Fin and Rudder
Stabilizer and Elevator
.....................
...................
You
Must Make
.............
....................
of
Wood
..................
....................
..................
............
.........
.........
........
3
3
4
4
5
6
6
6
6
6
7
WING ........................ 9
Wing Panels
Join the Wing Panels
Install Aileron Torque Rods
Sand
"Flats"
Fiberglass the Center Section
Install the Wing Tips
Install the Ailerons
Install
Install
Wing Dowels
Wing Bolt Plate
Fill Landing Gear Slots
Installing
FUSELAGE ASSEMBLY
Preparing Fuse Sides
Assemble Lower Fuselage
Drill Engine Mount
Install Servos and Pushrods
Install Bottom Sheeting
Mount the Wing to the Fuse
....................
.............
........
on LE and TE
........
.......
..............
...............
..............
............
...........
Retracts
................
........
.............
.........
..............
........
...........
........
9
14
14
15
15
16
17
18
18
18
19
19
19
21
22
22
24
24
Fitting Fuel Tank, Fuelproofing ..... 26
Install Turtle Deck
Assemble the Nose Section
FINAL ASSEMBLY
...............
........
.............
27
28
30
Sand the Fuselage ................ 30
Install Wing Fairings .............. 31
Install Wing Fillets
Shape the Fin Fillets
Mount Stabilizer and Fin
...............
..............
..........
32
33
34
Install Servos, Horns & Pushrods .... 35
Control Surface Throws
...........
36
FINISHING ....................36
Additional Fuelproofing
Seal
Off
Cockpit
.................
Prepare the Canopy
Balance the Airplane Laterally
Final Sanding
Covering
Glue the Hinges
Install the Pilot
...................
.......................
.................
..................
...........
...............
......
36
37
37
37
37
37
38
39
Glue Canopy in Place ............. 39
Wing Seating ................... 39
Re-install Engine & Radio ......... 39
Balance Your Model
Final Hookups and Checks
..............
.........
39
40
PRE-FLIGHT ..................40
Charge the Batteries
Find a Safe Place to Fly
Ground Check the Model
Range Check Your Model
..............
...........40
..........
..........
40
41
41
AMA SAFETY CODE ...........42
General
Radio Control
........................
...................
42
42
FLYING.......................42
Takeoff
........................42
Flying ......................... 42
Landing ....................... 42
Caution
TRIM INSTRUCTIONS
........................
.........
43
43
PARTS LIST ...................46
2-VIEW .......................48
Please inspect all parts carefully before starting to build! If any parts are missing, broken or de-
fective, or if you have any questions about building or flying this airplane, please call us at (217) 367 - 2069
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
INTRODUCTION
Congratulations! Thank you for purchasing the
Great Planes Ultra Sport 40! Jim Feldmann's original
design Ultra Sport 60 was featured as a construction
article in the August, 1989 issue of RC Modeler magazine, and has been hailed by many as "the best sport
flying airplane ever''! The design starts with the legendary "Kaos" wing planform, and features modem styling and state-of-the-art construction techniques. The
result is an ultra-stable, ultra-smooth flying airplane that
does what you want it to, no more and no less.
The Ultra Sport 40 is easy to build, totally predictable, smooth-flying and has very docile stall characteristics, making it the ultimate sport airplane for the modeler
who wants to fly with a higher degree of precision. Because it naturally tracks through maneuvers better than
other sport airplanes, you' 11 fly better when you' re flying
an Ultra Sport 40.
This is not a beginner's airplane! While the
Ultra Sport 40 is easy to build and flies great, we must
discourage you from selecting this kit as your first R/C
airplane. It is fast, highly maneuverable, and lacks the
self-recovery characteristics of a good basic trainer
such as the Great Planes PT Series airplanes. On the
other hand, if you have already learned the basics of R/
C flying and you are able to safely handle an "aileron
trainer" airplane such as the Great Planes Trainer
Series or Big Stick Series airplanes, the Ultra Sport 40
is an excellent choice.
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 and horns 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 arc not
already an experienced and knowledgeable R/C pilot at
this time.
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.
PRECAUTIONS
1. You must build the plane according to the plans
and instructions. Do not alter or modify the model as
represented by the plans, as doing so may result in an
unsafe or unflyable model. In a few cases the plans and
instructions may differ slightly from the photos. In those
instances you should assume the plans and written in-
structions are correct.
2. You must take time to build straight, true and
strong.
3. You must use a proper R/C radio that is in first
class condition, the correct sized engine and correct
components (fuel tank, wheels, etc.) throughout your
building process.
INSTRUCTIONS IN BOXES LIKE THIS
ARE VERY IMPORTANT AND SHOULD
BE FOLLOWED CAREFULLY.
COMMON ABBREVIATIONS USED IN
THIS BOOK AND ON THE PLANS:
Elev = Elevator
Fuse = Fuselage
LE = Leading Edge (front)
LG = Landing Gear
Lt = Left
Ply = Plywood
Rt = Right
Stab = Stabilizer
TE = Trailing Edge (rear)
Tri = Triangle
" = Inches
3
DECISIONS YOU MUST MAKE NOW
ENGINE AND MOUNT SELECTION
The recommended engine size range is as
follows:
.40 - .46 cubic inch displacement 2-cycle
.60* - .70 cubic inch displacement 4-cycle
*NOTE: Although not included in the
above engine size range, the OS MAX 48 SUR-
PASS also provides sufficient power to fly this
airplane.
The engine you select will determine how
you build the fuselage, so it is important that you
have the engine close at hand while building.
This kit includes a Great Planes MM40
engine mount that fits most .40 - .45 (2-cycle)
engines (only slight modification of this mount
is required to mount the OS40SF and OS46SF).
If you are installing an OS48 SURPASS
(4-cycle), you may purchase a Great Planes
MM60 mount. If you are planning to install the
OS70 SURPASS (4-cycle), you may purchase
the Great Planes MM60L mount. If you prefer,
you may purchase a custom engine mount for
your engine, or you may choose to install shock-
absorbing rubber-cushioned mounts.
NOTE: If you choose to power your Ultra
Sport 40 with a 4-cycle engine, keep in mind that
the RPM of your engine will be considerably
less than that of a 2-cycle engine; therefore, you
should select a higher pitch propeller to keep
the speed and overall performance roughly
equivalent to that of a 2-cycle engine. For
example, a 10x6 or 10x7 prop would be used
with a .40 (2-cycle) engine; but an 11x9 or
10x10 prop may be the best choices for a 4-cycle
engine.
LANDING GEAR CONFIGURATION
The Ultra Sport 40 may be built with either
a "taildragger" or "tricycle" landing gear
configuration, and a retractable main gear
may be installed if you want to really "clean
up" this airplane for ultra-smooth and precise
aerobatics.
There is not. however, room for a nose gear
retract; therefore, if you want retracts, you'll
have to use the "taildragger" configuration.
OTHER ITEMS REQUIRED
• Four-channel radio with 4 servos (additional channel and
retract servo required if retracts are being used).
• Propellers (see engine instructions for recommended
size)
Spinner (2-1/4" diameter)
Fuel Tank (10 or 12 ounce)
Main Wheels - 2 (2-1/2" dia. for fixed gear. 2-1/4" for
retract)
Nose Wheel -1 (2-1/4" diameter, required fortrike only)
Tail Wheel - 1 (1" diameter, required for taildragger
only)
• 5/32" Wheel Collars - 4 or 6
• 3/32" Wheel Collars - 2 (required for taildragger only)
• Iron-on Covering Material
• Silicone Fuel Tubing
• Wing Seating Tape (or silicone sealer... see instruc-
tions)
• Latex Foam Rubber Padding (1/4" thick)
• Dubro "E-Z Connectors" (or equivalent) - 2
• Main Gear Retracts (Dave Brown 2-Gear Main, or
equivalent)
• Plastic Pilot (Williams Bros. 2" scale) (larger 2-5/8"
scale pilot may be used, but requires modification)
4
DIE PATTERNS
Use this drawing to help you identify the die cut parts.
5
SUPPLIES AND TOOLS NEEDED GET READY TO BUILD
2 oz. Thin CA Adhesive
2 oz. Medium or Thick CA Adhesive
2.5 oz. 30-Minute Epoxy
Hand or Electric Drill
Drill Bits: 1/16". 5/64", 3/32", 7/64", 1/8", 9/64", 5/32",
1. Unroll the plan sheet. Re-roll it inside out to make
it lie flat. NOTE: You may cut the plan into two sections
("wing" and "fuselage"), by cutting along the "cut
line'' shown on the plan.
13/64". 7/32", and 1/4"
Sealing Iron
Heat Gun
Hobby Saw (Xacto Razor Saw)
Xacto Knife, #11 Blades
Pliers
Screw Driver
T-Pins
Straightedge
Masking Tape
Sandpaper (coarse, medium, fine grit)*
T-Bar Sanding Block, or similar
2. Remove all parts from the box. As you do, figure
out the name of each part by comparing it with the plans
and the parts list. Using a felt tip pen, write the part name
or size on each piece to avoid confusion later. Use the
die-cut patterns shown on page 5 to identify the die-cut
parts and mark them before punching out. Save all
scraps. If any of the die-cut parts arc difficult to punch
out, do not force them! Instead, first cut around the parts
with an Xacto knife. Afterpunching out the die-cut parts,
use your T-Bar or sanding block to lightly sand the edges
to remove any die-cutting irregularities.
Waxed Paper
Lightweight Balsa Filler
1/4-20 Tap, Tap Wrench
Vaseline Petroleum Jelly
3. As you identify and mark the parts, separate them
into groups, such as fuse (fuselage), wing, fin and stab
(stabilizer), and hardware.
Isopropyi Rubbing Alcohol (70%)
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 before covering.
TYPES OF WOOD
BALSA BASSWOOD PLYWOOD
"TAIL FEATHERS"
BUILD THE FIN AND RUDDER
1. Find the following parts: 1/4" balsa fin front,
fin rear, rudder front, rudder rear and rudder bottom. Compare the parts to the plans to make sure you
have the correct parts. Also find the 1/4 "x 9/16" x 15"
balsa stick, and the 1/8" x 1/4" x 12" balsa stick.
2. Cut the 1/4" x 9/16" x 15" balsa stick into three
pieces having lengths of: 5-1/4", 4-3/4" and 4-3/4". The
5-1/4" lengthis the fin tip. Mark the 4-3/4" pieces "stab
tip".
3. Cut the 1/8" x 1/4" x 12" balsa stick into 5 pieces
having lengths of: 2-3/4", 2-5/8", 2-5/8", 1-5/8" and
1-5/8". The 2-3/4" length is the rudder end. The
remaining pieces are the elevator ends.
6
4. Working on a flat surface covered with waxed
paper, glue the fin front to the fin rear, then glue on the
fin tip. Sand the front of the fin tip to blend with the fin.
as shown on the plan.
5. Using a T-bar or sanding block, sand both sides
of the fin smooth. Then sand the leading edge and top
edge to a rounded shape, as shown on the plan. Draw a
centerline along the trailing edge of the fin to mark the
hinge line.
6. Glue the rudder front to the rudder rear, then
glue on the rudder bottom and rudder end.
10. If you are building a "taildragger", check the
plans and mark the location of the tailgear on the rudder.
Drill a 7/64" hole in the rudder, and groove the rudder
leading edge to accept the tailgear wire and the nylon
tailgear bearing.
BUILD THE STABILIZER AND
ELEVATORS
7. Draw a centerline all around the edges of the
rudder (This will help to maintain symmetry when
sanding).
8. Using a sanding block and coarse (50 or 80-grit)
sandpaper, sand both sides of the rudder to a taper as
shown on the plans. The trailing edge should end up
approximately 3/32" wide and have a rounded shape.
(Do not sand to a sharp edge). Sand the bottom edge to
a rounded shape. Sand the leading edge to a' 'V-shape''
as shown on the plan.
1. Find the following parts: 1/4" balsa stab front,
stab rear and elevators. You'll also need the 1/4" stab
tips and 1/8" elevator ends that you previously cut, and
the 1/8" wire elevator joiner.
2. Glue the stab front to the stab rear. Then glue
on the stab tips. Sand the front of the stab tips to blend
with the stab.
3. Glue the elevator ends to the elevators and sand
to blend.
9. Hold the fin and rudder together and mark the fin
tip at the rudder trailing edge. Cut off the fin tip and sand
it to match the rudder as shown on the plan.
4. Sand both sides of the stab smooth, then sand the
leading edge and tips to a rounded shape. (Leave the
7
center portion of the LE square). Draw a centerline
along the trailing edge of the stab to mark the hinge line.
5. Draw a centerline all around the edges of the
elevators.
9. Accurately drill holes in the elevators for the
1/8" wire joiner. Begin by drilling a 1/16" or 5/64" pilot
hole, then drill the final hole to a depth of 7/8" with a
9/64" drill bit. (The hole is drilled slightly oversize to
allow for positioning, and to create a hard epoxy
"sleeve" around the wire).
6. Sand both sides of the elevators to a taper as
shown on the plans. The trailing edge should end up
approximately 3/32" wide and have a rounded shape (do
not sand to a sharp edge). Sand the leading edge to a "V-
shape" as shown on the plan.
7. Temporarily tape the elevators to the stab, providing 1/16" clearance between the elevator end and the
stab tip.
10. Using an Xacto knife, sharpen the inside of one
end of a 1/8" diameter brass tube and use it to cut grooves
in the leading edge of the elevators to accept the joiner
wire.
11. Roughen the joiner wire with coarse sandpaper,
then clean the wire thoroughly with alcohol to remove
any oily residue.
8. Lay the 1/8" wire elevator joiner in place on the
elevators and mark its outline using a fine point felt-tip
pen.
12. Trial fit the joiner wire into the elevators, then
glue it in using 5-minute or 30-minute epoxy. When
gluing, lay the elevator leading edges along a straightedge to insure perfect alignment.
8
INSTALL THE HINGES (Do not glue)
NOTE: One-piece molded polypropylene hinges
are supplied in this kit. If you choose to use these
hinges or the "pinned"-type hinges, you may 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.
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
elevators against the stab TE and transfer the marks over
to the stab.
CAUTION!!!: You must use extreme care
when cutting hinge slots with an Xacto
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.
from your local hobby dealer). Many expert
modelers prefer to use a wing jig for high
performance airplanes, as it helps to insure a
straight, warp-free wing, especially if you do not
have a workbench or building board that is perfectly
flat. If you choose to use the Wing Jig, please read
the instructions that are included with the jig before
beginning.
BUILD THE WING PANELS
NOTE: It will be helpful to build the wing on a
piece of "Celotex" or other semi-soft (and flat)
surface, into which you may easily stick pins to
firmly hold down the wing parts while building, to
avoid warps.
1. Tape the plan to your flat work surface, and
cover the wing drawing with waxed paper (so you won't
glue the wing to the plan!). NOTE: If your work space
is limited, you may cut the left and right wing half
drawings apart.
2. The shaped and notched wing leading edges
(LE) and trailing edges (TE) are fastened together by
thin strips of balsa. Separate them by folding until the
balsa breaks. Sand away the excess balsa that remains
along the edges after breaking them apart, using a T-bar
with 100-grit sandpaper.
2. Cut the hinge slots on the accurate centerlines
which you previously drew, using an Xacto knife or a
hinge slotting fork and hook. (See Step 7 on Page 17)
3. IMPORTANT! Condition or "break-in" the
hinges by folding them back and forth several times.
4. Insert the hinges into the slots and trial fit the
rudder and elevators in place on the fin and stab. Do not
glue the hinges until after you have covered the
model.
WING
NOTE: The following instructions explain how to
build the wing directly on the plans. An alternative
method is to use a Great Planes Wing Jig (available
3. Before using the 1/4" x 3/8" x 27-1/4" hard balsa
spars, 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 (if any) are on the outer half of the wing
panel (toward the tip), where they will be least affected
by high stress. If the spars are warped slightly, try to
"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
TWO WARPED SPARS INSTALLED
THIS WAY WILL RESULT IN A
WARPED WING
9
4. Find the 1/8" x 3/8" x 13-3/8" basswood spar
doublers. Sand one end of each spar doubler to a taper
as shown in the " Wing Spar Detail" on the plan. Glue
the spar doublers to the spars, and sand off any excess
glue.
5. Carefully punch out all the die-cut 3/32" balsa
wing ribs. Sand the edges slightly to remove any diecutting irregularities.
NOTE: If you will be installing a retractable
landing gear, disregard Steps 6 and 7.
6. Note that the wing plan shows two alternate
locations for the main landing gear blocks. Note also that
Ribs W-2, W-3 and W-4 have partial cutouts foreach of
the two locations. If you are building your plane as a
taildragger, cut out the front notches in these ribs. If
you are building your plane with a tricycle gear, cut out
the rear notches. (If you will be installing retracts, do not
cut out any of the notches).
7. Glue the die-cut 1/16" ply landing gear dou-
blers to ribs W-2, W-3 and W-4. Be sure to glue them
to the correct side of the ribs, as shown on the plan (make
a right and a left set). Sand the doublers even with the
edge of the ribs.
8. Prepare the leading edge sheeting as follows:
Edge glue the 3/32" x 1/2" x 7-1/2" balsa sheets to the 3/
32" x 3" x 27-1/4" balsa sheets as shown here...
NOTE: Follow steps 9 through 34 to build
the RIGHT wing panel, then repeat these
steps to build the LEFT wing panel.
9. Pin one of the spars to the plan with the spar
doubler up and toward the root. NOTE: The spars are
cut slightly too long. Center the spar on the plan so an
equal amount protrudes on both ends.
10. Place the ribs on the spar in their approxi-
mate position, but do not glue. NOTE: Make sure ribs
W-2, W-3 and W-4 are installed with the LG notches
down, and W-l is installed with the servo opening
pointing up.
Now measure and mark the balsa sheeting (see
sketch below), then cut the angle in the sheeting, cutting
along a metal straightedge for accuracy.
CUT FIRST SLOT TO
ANGLE OF DIHEDRAL
GAUGE
NOTCHED LEADING
EDGE
11. Notice that all notches in the LE and TE are
vertical. However, rib W-l will be installed at a slight
angle using the Dihedral Gauge. Therefore, you should
now modify the notch for W-1 by cutting it to the angle
of the rib. You may determine the approximate angle of
the cut by holding the Dihedral Gauge (DG) against the
LE as shown above.
10
12. Insert the rear ends of the ribs into the
notches in the TE. then block up the TE with the 1/4"
balsa TE Jig supplied. NOTE: The narrow end of the
TEjig is at rib W-11. Pin the jig to the building surface.
13. PintheTEtotheTEJig.makingsuretheribs
line up with the plan.
14. Glue ribs W-2 through W-11 to the TE.
(Apply glue sparingly, to avoid gluing the TE to the TE
Jig).
15. Insert the front ends of the ribs into the
notches in the LE. NOTE: Position the LE as shown in
the sketch.
CENTER L.E. VERTICALLY
ON FRONT OF RIBS
the TE, LE and bottom spar. Glue all other ribs to the
LE and bottom spar.
17. Glue the top sparin place, making sure you
do not change the angle of W-1.
18. Glue the pre-cut 3/32" balsa vertical grain
shear webs to the rear edge of the spars in all rib bays
except between ribs W-1 and W-2. NOTE: You may
wish to trial fit, mark, and trim each web before gluing
in. NOTE: The webs must be securely glued to the
spars, but it is not necessary to glue the webs to the ribs.
L.E.
16. Make sure the ribs are fully down on the plan
and all ribs are inserted into the LE notches. Angle rib W-
1 slightly using the dihedral gauge (DG). Glue W-1 to
19. You will now make a "pocket" for the
1/16" ply dihedral brace by installing a 3/32" balsa
11
web 1/16" behind the spars. Sand one of the 3/32" x 2"
x 2-5/8" balsa horizontal grain webs for a good fit
between W-l and W-2. Using the 1/16" ply dihedral
brace as a temporary spacer, glue the 3/32" web to W-l
and W-2.
the following step and go through a "dry run*
before actually gluing.
20. Glue the die-cut 1/8" ply front web to the
front edge of the spars between ribs W-l and W-2.
NOTE: In the next steps, maintain straightness
by keeping the wing down on the flat surface and
on
the
TE
Jig.
21. Lightly sand the tops of the ribs to blend
with the notched trailing edge; then glue one of the 3/32"
x 1-3/8" x 27-1/4" balsa trailing edge sheets in place.
NOTE: The edge of the TE sheet may not be exactly
straight, but just position the sheet so it slightly overlaps
the TE, and any overlap can be sanded off later.
22. Before applying the leading edge sheeting in
the next step, use your T-bar to lightly sand off the edges
of the shear webs and smoothly blend the ribs to the spar.
24. Position the leading edge sheeting at the rear
edge of the notched LE so there is an equal amount
protruding on both ends of the wing. Using thin CA, glue
the front (beveled) edge of the leading edge sheeting to
the back edge of the leading edge. Now wet the top
surface of the sheeting so it will bend easier. Apply thick
CA glue to the top edge of the ribs and to the front half
of the spar, then immediately bend the sheeting down
onto the ribs and spar. Hold the sheeting down with
masking tape, pins and your hands until the glue has set.
25. Using the 3/32" x 3" x 8-1/4" balsa sheets,
glue the top center section sheeting in place as shown on
the plan.
23. Prepare the 3/32" balsa leading edge sheet -
ing by sanding the front edge to a slight bevel so it will
fit snugly against the back of the leading edge.
NOTE: It will be helpful to have the following
items handy for the next step... thin CA, thick CA,
a wet cloth, masking tape and T-pins. Read through
NOTE: If you are installing retracts, disregard
steps 26 through 29.
26. Remove the wing from the building board
and trial fit the long grooved hardwood LG block into
the notches in dbs W-2, W-3 and W-4 (see the landing
12
gear detail drawing on the wing plan for proper positioning). File the notches if necessary for a good fit. Now use
epoxy to securely glue the block in place.
27. Epoxy the 7/16" x 5/8" x 7/8" hardwood
block to the LG block and to the 1/16" ply doubler on rib
W-2. as shown on the plan and in the photo, then epoxy
the small hardwood block to the other end of the LG
block and to the 1/16" ply doubler on rib W-4.
Photo of finished wing with retract mechanism removed.
the bottom of the wing, in the location shown on the
plan. Lock and strengthen the joints between the
1/4" ply rails and the 1/16" ply rib doublers by
gluing 1/4" balsa triangle stock to these joints. You
should also now do some planning and trial fitting of
the retract and pushrod, customizing the installation
as necessary to accommodate your retracts.
Installing retracts requires careful planning and
a lot of trial fitting; therefore, you should take the
time now to plan out your installation.
31. With the wing upside down, again use the
TE jig to support the TE. Then install the bottom TE
sheeting, LE sheeting and Center Section sheeting, cutting and fitting the sheeting around the LG block as
necessary. IMPORTANT NOTE: To insure a
straight wing, you must pin or weight the TE securely
down on the TEjig while the bottom sheeting is glued
in place!
28. Drill a 5/32" hole down through the grooved
LG block and the 7/8" block. Line up the drill so you are
drilling straight down through the middle of the 7/8"
block.
29. Trial fit the 5/32" diameter main landing
gear wire into the landing gear block at this time. Cut or
file the groove and hole in the landing gear block as
necessary for a good fit.
30. Using a razor saw, carefully cut off and sand
all excess sheeting, spars, LE and TE even with W-1 and
W-ll.
NOTE: If you will be installing retracts, now is
the time to glue in the 1/16" ply die-cut rib doublers
to the front portion of ribs W-3 and W-4. (Make
sure the front rib doublers are on the outboard side
of W-3 and the inboard side of W-4). This is also the
time to install the 1/4" ply retract mounting rails on
32. From the 3/32" x 1/4" x 30" balsa sticks, cut
and glue cap strips to all exposed ribs, top and bottom.
HINT: Foreasierpositioning of the cap strips, firstmark
the location of each rib on the LE and TE sheeting.
33. Trim the sheeting flush with ribs W-l and
W-11 and sand the entire wing panel smooth. Sand the
leading edge to smoothly blend with the LE sheeting (see
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the rib cross-sections on the plan for the desired LE
shape).
34. Mark and cut out a 1/16" slot in W-l just
behind the spars, for the dihedral brace.
35. Now go back and repeat Steps 9 through 34 to
build the left wing panel.
JOIN THE WING PANELS
3. Mix up a batch of 30-minute epoxy and push
some into the dihedral brace slots. Smear epoxy on the
spar ends, and on both sides of the 1/16" ply dihedral
brace. Slide the dihedral brace in place, push the wing
panels together and immediately proceed to the next
step.
4. With the wing tips blocked up 1 -inch, carefully
align the LE and TE of both wing panels at the center and,
while holding them in correct alignment, apply thin CA
glue to "lock" the panels together. Do not apply CA
glue to any area that is already coated with epoxy.
Allow the epoxy to fully harden before disturbing the
wing.
NOTE: Read steps 1 through 4, then make a "dry
run" through these steps before actually
proceeding.
1. Lay a piece of waxed paper down at the center of
the wing, place the two wing panels together at the center,
and block up both wing tips 1-inch. Sand the wing
panels at the center so they will fit together without a gap.
2. Trial fit the 1/16" ply dihedral brace to make
sure it will readily slide into place.
5. Sand the wing joint smooth all around.
INSTALL AILERON TORQUE RODS
1. Roughen the short end of the aileron torque
rods with 100-grit sandpaper, and file the same end to a
wedge shape.
FILE END TO
WEDGE SHAPE
NOTE: 30-minute epoxy is strongly
recommended for the wing joining process.
2. Roughen the surface of the plastic bearing tubes
with 100-grit sandpaper.
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3. Clean the torque rods and bearing tubes with
alcohol.
SAND "FLATS" ON LE AND TE
4. Find the two grooved, tapered balsa center
trailing edge pieces. Lay them on the plan, mark and cut
them off to match the plan for length and angle at the
centerline.
5. Trial fit the torque rods into the center TE pieces.
Determine from the plan where to cut the clearance
notches, which will permit the torque rod horns to travel
freely. Also cut small clearance notches in the wing TE.
Note: The torque rod horns must exit the TOP of the
wing!
6. Slide the plastic bearings toward the threaded
end of the torque rods, then use a toothpick to apply a
small amount of petroleum jelly to the ends of the plastic
tubes (to help prevent glue from getting inside and
locking up the torque rods).
7. Use 5-minute epoxy or CA to glue the plastic
bearing tubes into the grooves in the center TE pieces.
Wipe off any excess glue and allow it to harden.
1. Study the wing plan near the wing centerline.
Note that the center portion of the LE and TE must be
sanded flat.
2. Sand approximately 5/32" into the LE at the
centerline, and approximately 3/32" into the TE at the
centerline. (The flats will end up approximately 4-1/2"
wide at the LE, and 2" wide at the TE).
FIBERGLASS THE CENTER SECTION
NOTE: Because of the high stresses in the center
of this wing, fiberglass reinforcement is
REQUIRED. Please do not omit this important
section!
NOTE: If you have previous experience with
applying fiberglass, feel free to use your favorite
method, providing that it results in a strong bond
between the glass cloth and the wood. If this is your
first time, we offer the following suggested method,
which is the fastest and easiest we have seen.
8. Trial fit the trailing edge/torque rod assemblies
onto the wing trailing edge. Sand the center trailing edge
pieces slightly where they join, for a good fit. Glue these
pieces in place with epoxy. HINT: Use masking tape to
hold these pieces to the wing TE. to aid in correct posi-
tioning.
1. Make location marks for the fiberglass rein-
forcement cloth, 1-1/2" each way from the wing center-
line.
2. Trial fit the 3" wide fiberglass cloth in place.
You can use a scissors or a paper punch to cut holes in the
glass cloth for the aileron torque rod horns.
3. Wrap small pieces of masking tape around the
threaded portion of the aileron torque rods to protect
them from the spray adhesive in the next step.
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