Century Helicopter Products Twinstar CN1075 User manual

TwinstarTwinstar
TwinstarTwinstar
Twinstar
ARF HelicopterARF Helicopter
ARF HelicopterARF Helicopter
ARF Helicopter
Detail Manual
- HIGH QUALITY FIBERGLASS
- MAIN ROTOR DIAMETER 49.5 in
-TAILROTORDIAMETER 9.7 in
- HEIGHT 15.2 in
- BLADES 550mm
- ENGINE 32 ~ 38
Century Helicopter Products
Designed and Developed in USA
2nd Edition March 2002, All rights reserved.
Specifications

2
Congratulations on your purchase of Century Helicopters Product’s Twinstar scale helicopter kit. The
ARF helicopter is the beginning of a new breed of AA
AA
Almost RR
RR
Ready to FF
FF
Fly pre-painted scale helicopters that
are simpler to build, easier to see and look fantastic. For those that have the complete kit version,
you have great flexibility to make choices when installing the mechanics and apply an awesome
paint design of your own. Whether you are just beginning in helicopters, wanting to start in scale
or an accomplished pilot, Century offers a helicopter to fulfill your dreams in scale. Century has
combined their world class helicopter mechanics with awesome ARF fiberglass fuselages designed
to mount directly inside without modifications.
Building Instructions for:
CN1075 Twinstar Scale Helicopter Kit
CN1075A Twinstar Painted Scale Helicopter w/ ARF Mechanics
IntroductionIntroduction
IntroductionIntroduction
Introduction
WarningWarning
WarningWarning
Warning
The Twinstar scale helicopter kit must be assembled and installed in accordance with these instructions.
Failure to do so could cause failures in the fuselage or the helicopter mechanics. Such failures could result
in serious injuries. It is strongly recommended that if you are in doubt of your abilities, you should seek
the assistance from experienced radio control modelers and associations. As manufacturer, we assume no
liability for the use of this product.
Pre-assembly InformationPre-assembly Information
Pre-assembly InformationPre-assembly Information
Pre-assembly Information
Upon opening the Twinstar scale helicopter, you will find the major fiberglass and clear component parts
and hardware bags. Hardware is identified by the size of the fastener or part. This is done for ease of
assembly. Be careful when opening bags as not to lose any hardware, whenever possible, keep all screws
in a container until you use them up through the assembly process. Care has been taken in the filling and
packaging of each bag. However, mistakes do happen. If there is a shortage or missing hardware, please
contactus at:
Century Helicopter Products
523 Sinclair Frontage Road
Milpitas, CA 95035
Fax:[phone]
www.centuryheli.com

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Detail Instructions:Detail Instructions:
Detail Instructions:Detail Instructions:
Detail Instructions:
This manual has been written to cover the assembly of the Twinstar scale helicopter kit and the ARF Painted
version. This is the detail construction of the Twinstar fuselage components that work in cooperation with the
scale mechanics instruction manual. For modelers building the kit version, all mechanics fitting (landing gear,
muffler exhaust, tail gearbox, fuel system components and radio mounting) must be completed before the fuselage
is painted as this will reveal any addition access holes that need to be cut-out. This is much simpler before painting
is complete.
Building Level:Building Level:
Building Level:Building Level:
Building Level:
Level 1. Beginners will follow all steps and sections in order as they are laid out, this is a longer process that
involves building the mechanics completely, running-in the engine and then disassembling the helicopter to
install into the completed fuselage.
Level 2. Intermediate to expert modelers can complete the fuselage and build & install the helicopter simulta-
neously using a previously run-in engine.
Instructional InformationInstructional Information
Instructional InformationInstructional Information
Instructional Information
Every attempt has been made to ease the assembly of your helicopter, at each step where there are complex
assemblies, there are detailed drawings, photos and written instructions to walk you through each step. Remember
to take a few minutes before each step to carefully examine the instructions in order to become familiar with the
parts and assembly sequence before beginning that step.
Twinstar Detail Construction Manual
Symbols used to help assist you in building:
Apply
“Goop”
Special
Attention
Repeat Step
as Specified
Apply
Threadlock
Partially
Tighten
Purchased
Separately
Helpful
Tip
Cut away
ShadedPortion
HardwareDescriptionand Identification:
M3x6 = 3 x 6mm and can refer to screws or fasteners:
Required Items to complete the Twinstar Fuselage kit: Recommended Tools & Accessories:
Pencil & Ruler Clear Fuel Proof Paint
Slow CA Glue 1/4” Paintbrush
1/16”, 1/8” Drill Bit Scissors
RegularHandTools Paint,primer and filler*
Masking Tape 320 Grit Sandpaper
Lead Weight 30 Minute Epoxy
FoamRubber Sanding Blocks*
PermanentMarker Locktite (liquid thread lock)
Rubbing Alcohol Disposable epoxy brushes
Moto Tool w/ sanding accessories
Remote Glow Plug Connector (CN2222)
Remote Fueling Valve (CNT4444)
5.0mm Open End Wrench
5.5mm Open End Wrench
7.0mm Open End Wrench
* For unassembled fuselage kit version.
M3x6 Self Tapping Screw
M - metric
3 - diameter
6 - length
M3x10 Socket Cap Screw
M - metric
3 - diameter
6 - length

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The mechanics (completely built helicopter without body) should be flight ready. At this point the helicopter
should essentially be together without the fuselage, this can be accomplished with the scale mechanics instruction
manual that comes with the kit and ARF versions. For the kit version, complete all the fitting before painting.
The final items that need to be finished are:
1. The battery pack and the receiver (wrapped in foam) are installed in front or below the battery tray. If mounting
infront for balance, suitable anchoring need to be fabricated to securely hold the items.
2. The antenna needs to be routed to the tail gearbox with out contacting any metal or wiring. Optional short whip
antennasare great but either methodneedstoberouted correctly.
3. Remote glow plug adapter and fueling system needs to be installed (purchased separately).
4. The engine Run-in will require 2-4 tanks of fuel to get the engine running smoothly (with main blades).
5. Rudder pushrod length needs to be shortened and adjusted based on the rudder setup instructions.
6. During the Run-in, cycle the throttle to lift-off and trim the rudder while setting up the gyro.
Do not fly the helicopter at this stage, the mechanics are designed for the scale fuselage and is not balanced for
extended hovering or forward flight. Also note that the is no tail support strut or tail fins (apart of the fuselage)
for stability.
Section Two: Fuselage PreparationSection Two: Fuselage Preparation
Section Two: Fuselage PreparationSection Two: Fuselage Preparation
Section Two: Fuselage Preparation
STEP 1 Muffler Cutout & ClearanceSTEP 1 Muffler Cutout & Clearance
STEP 1 Muffler Cutout & ClearanceSTEP 1 Muffler Cutout & Clearance
STEP 1 Muffler Cutout & Clearance
If you are installing the optional CN3058 Scale 30 size
muffler the cutout in the fuselage is already completed.
The fuselage is designed to use the scale muffler from
Century, either the CN3058 (30 size) or the CN3059
(46-50 size) that can be purchase separately. These
mufflers are box like and fit very close to the scale
mechanics making them an ideal choice. Standard
torpedo style mufflers simply will not work because they
require cutting out the side of the fuselage. It is common and
recommended to use an optional exhaust diverter that extends
the muffler exhaust out past the edge of the fiberglass, however it
maybe necessary to enlarge the hole in the fuselage depending on the
type used, Century offers CN3014, CN3015 & CN3016 that can be
trimmedtofit.
Section One: Completing the helicopter mechanics.Section One: Completing the helicopter mechanics.
Section One: Completing the helicopter mechanics.Section One: Completing the helicopter mechanics.
Section One: Completing the helicopter mechanics.
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For the CN3059 Scale 46-50 size muffler, the cutout will need to be slotted as the position of the exhaust outlet is
slightly offset. If another exhaust system is going to be installed, make the cutout for the exhaust at this time.
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No further work is necessary if mounting the optional CN3058 Scale muffler. For all other mufflers, trace the
template in the back of the scale mechanics manual, install the preferred muffler and mark the hole for the exhaust.
Using a sharp pencil, pierce the holes for the side frame and the appropriate exhaust center mark that corresponds
to your muffler. While holding the rear fuselage upside down, align the pierced “side frame” holes. Using a
marker, mark the center and draw the circle for the exhaust hole. Using a moto-tool and a grinding stone, make
the hole in the bottom of the fuselage and the bottom hatch. Alternately, the hole can be drilled inside the final
diameter and filed or hand sanded to the final size.
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During flight the fuselage will vibrate and depending on the rotor speed, this vibration can be strong enough to
have the some part of the fiberglass contact the mechanics. The common result can range from a mild abrasion to
actual cracking of the fuselage. To eliminate this problem, there are two aluminum strips included with a 3mm
hole pre-drilled in one end. Measuring from the end with the hole, make a mark at 13mm and 63mm where the
strip will be bent to match the photo. Using a set of pliers that have a smooth, straight jaw (or possibly a table vise)
bend the first 13mm mark at 90° degrees downward, bend the second 63mm mark 90° degrees upward. The last
portion of the support should be curved to match the vertical side wall the the fuselage. At a minimum apply vinyl
tape (not included) to the vertical support where it will contact the fuselage, using a thin foam weather-stripping
would be better to dampen all vibration. Attach the support to the forward M3x16 Socket Cap Screw on the lower
side frames. After the mechanics are in the
final position, some slight adjustment is
possible by bending the last segment to fit.
STEP 2 Fuselage Side SupportsSTEP 2 Fuselage Side Supports
STEP 2 Fuselage Side SupportsSTEP 2 Fuselage Side Supports
STEP 2 Fuselage Side Supports
Final shape of the fuselage supports before
applying tape or weather-stripping. Remem-
ber to thoroughly clean the parts before
applying any adhesive tape.
Fuselage supports
[CN1075-5]
An alternate to using tape is to apply “Goop” or “Zap-a-Dap-a-Doo” type of adhesive to the seams of the
supports, effectively bonding them to the fuselage sides. These types of adhesives can be removed at a
later time by scoring and cutting through the joints. With the mechanics temporarily positioned, mark with
pencil the outline of the support and thoroughly clean the fiberglass surface with rubbing alcohol.
Apply tape, foam
tape or semi-perma-
nently bond in place.
Front M3x16
Socket Cap Screw
2.52.5
2.52.5
2.5
HexHex
HexHex
Hex
13mm 50mm
Bend at the
dashed lines.
Fuselage supports x 2
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Insert the main mechanics (with the main shaft removed) with the completed rudder pushrod guides permanently
installed, insert the mechanics past the pre-drilled landing gear holes until the end of the tail boom
extends past the fiberglass by 1/2” [12mm], be carefull not to pull out the tail drive shaft with the
bearings as the forward joint can be disengaged, requiring disassembly to re-attach. As-
semble the tail gear box with the tail blade assembly onto the right side (as viewed
from behind) over the tail boom, aligning the tail input gear into the mating
recesses in the gearbox. Liberally apply grease to the tail gears and close the
tail gearbox with left side, securing them together with two M3x12, one
M3x10 Socket Cap screws and three M3 Locknuts. Insert two
M3x20 Socket Cap screws from the right side of the gearbox and
attach two 10mm threaded fin mounts using threadlock. The fin
mounts will need to be held with smooth jaw pliers to be suffi-
ciently tightened.
Cut a piece of 1/4” radio foam 1/2” wide by 2” long (same as
used to isolate receiver and battery from vibration), while
moving the mechanics to align to the landing gear holes, insert
the foam in-between the metal tail boom and the fiberglass tail
section, this will cushion the tail boom but make disassembly
simple.
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Before the tail gear box can be assembled onto the
tail boom, the tail boom must be secured to
the mechanics, the tail pushrod must be
installed and the tail pushrod guides
must be close to their final posi-
tions, however there is no access
afterthe mechanicsare installed.
Attach the tail boom with the
drive shaft assembly and ensure
the drive shaft is engaged in the
transmission drive shaft. Slide the
three tail pushrod guides onto the
tail boom and roughly position them equally spaced along the tail boom. Insert the long rudder pushrod from the
end of the tail boom but do not attach the plastic pushrod coupler. Complete the remainder of Step 4-9 in the
mechanics manual, including attaching the rudder ball link to the tail pitch lever but do not grease the gears in the
gearbox. Slide the pushrod back and forth to get the best positioning for the tail guides. Once smooth operation is
attained, tape each guide to the tail boom. Following the rudder setup instructions, shorten the threaded section
closest the plastic coupler, there is enough thread to remove 5-6mm from each end to position the tail bellcrank at
the correct angle.
Now
remove the tail gearbox and take the entire main mechanics (removing the main shaft & muffler makes
this easier) with tailboom and insert into the rear fuselage and observe where the pushrod exists the end of the
fiberglass tail boom. Make a pencil mark where the tail pushrod exits the fiberglass, this should be directly under-
neath the tail boom. The rearmost guide may need to be moved forward to properly fit inside the fiberglass tail
boom and a 3/32” [2.5mm] slot cut into the bottom of the tail boom to get proper clearance and free movement. If
needed, cut the slot with a moto-tool or razor saw and file the edges smooth. A “trim and test” procedure maybe
necessary to repeat until the slot is long enough. Once completed, glue the pushrod guides onto the tail boom with
slow-CA (only a few drops around the outside are needed to sufficiently attach the guides.
STEP 3 Attaching the Tail Boom & Tail PushrodSTEP 3 Attaching the Tail Boom & Tail Pushrod
STEP 3 Attaching the Tail Boom & Tail PushrodSTEP 3 Attaching the Tail Boom & Tail Pushrod
STEP 3 Attaching the Tail Boom & Tail Pushrod
In addition to
Step 4-9 in
Scale Manual
STEP 4 Tail Gearbox Assembly & Vertical Fin MountsSTEP 4 Tail Gearbox Assembly & Vertical Fin Mounts
STEP 4 Tail Gearbox Assembly & Vertical Fin MountsSTEP 4 Tail Gearbox Assembly & Vertical Fin Mounts
STEP 4 Tail Gearbox Assembly & Vertical Fin Mounts
M3x20 SHCS x 2
Threaded Fin
Mounts x 2
[CN1075-5]

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STEP 5 Vertical Tail FinSTEP 5 Vertical Tail Fin
STEP 5 Vertical Tail FinSTEP 5 Vertical Tail Fin
STEP 5 Vertical Tail Fin
The vertical tail fin is attached with the short portion on the bottom. Slide
one M3 Washer onto one M3x12 Socket Cap screw and insert through
the pre-drilled hole in the vertical fin, repeat for the second hole. Apply
thread lock to the exposed threads and thread into the vertical fin mounts
already installed on the tail gearbox. Be careful, tighten until snug and
then only a 1/16” of a turn more. Warning, these fasteners only hold the
fin in place, overtightening will crush the fin.
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The edges of the fin need to be sanded before the paint in applied.
After painting, the holes for the screws will need to be re-drilled to
remove any paint that accumulated in the holes.
M3x12 SHCS x 2
M3 Flat Washer x 2
[CN1075-5]
STEP 6 Landing Gear & Muffler AttachmentSTEP 6 Landing Gear & Muffler Attachment
STEP 6 Landing Gear & Muffler AttachmentSTEP 6 Landing Gear & Muffler Attachment
STEP 6 Landing Gear & Muffler Attachment
Vertical Fin
(unfinished)
[CN1075-3]
As there is enough space to attach the 30 size muffler after the mechanics are secured to
the landing gear, remove it for now. If you have chosen to install the 46-50 size engine, it
is very important that the muffler screws are installed loosely in the engine before the side
frames are attached, if this is not the case, do it now. Place the mechanics and the rear fuselage on top of the
assembled landing gear. Slide one M3 Flat Washer onto one M3x15 Socket Cap screw and insert from the bottom
of the front landing strut, through the fiberglass floor and the align to the front hole of the mechanics. Attach one
M3 Locknut on the inside using pliers to hold the nut while the bolt is tightened from below. Repeat for the other
side. To attach the rear strut, repeat the same procedure but tip the mechanics over the side of a table. Using a
5.5mm nut driver, place a drop of grease on the top of the locknut and insert into the nut driver (this will hold the
nut from falling out) and carefully insert the nut driver between the side of the mechanics and the fuselage. You
will need to maneuver past the angle supports but with patients and keeping the nut driver horizontal, the rear
locknuts can be secured. This can also be accomplished with the muffler installed but more patience is needed as
you are unable to see the bolt. Repeat for the other side,
this time with the fuel tank as the challenge.
It is assumed that the muffler holes have been
cut for the muffler to be installed, the edge of
the hole should be fuel proofed with a Polyure-
thane paint or simple clear nail polish to seal
the paint finish to the fiberglass. There is
enough room to use a long allen key or hex
screwdriver to access the muffler bolts. If
you have been test flying the mechanics,
clean the muffler bolts, the muffler threads
and the through holes on the engine with
rubbing alcohol before assembling. Make
an aluminum gasket if none is provided
with the muffler, after tightening the bolts,
torque an additional 1/16” of a turn.
Finally, run the pressure line back to the
fuel tank and arrange any other fuel lines
for optional filler valves or fittings.
M3
Locknut
on top.
M3x15 SHCS x 4
M3 Flat Washer x 4
M3 Locknut x 4
Rear Body with
Bottom Hatch
(unfinished)
[CN1075-2]
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The windshield in the kit version needs work as compared to the ARF version where it is ready to be bonded to
front body. After the fuselage is painted, the windshields are attached using “Goop” or “R/C 56 Canopy Glue”
types of adhesives. For “Goop” it is important to notice that the recessed surface on the front body is 1/4” [6mm]
wide that provides the bonding surface for the windshield. This fuselage is designed to have the pilot and rearward
windows open, for engine cooling purposes, resist the urge to enclose these windows, as it can cause an engine to
overheat and subsequently quit. All very bad for scale helicopters.
STEP 7 Horizontal StabilizersSTEP 7 Horizontal Stabilizers
STEP 7 Horizontal StabilizersSTEP 7 Horizontal Stabilizers
STEP 7 Horizontal Stabilizers
After marking, drill a 3/32” [2.5mm] hole centered at the
mark on the stabilizer and drill 7/8” [22mm] deep from the
end. This is for the threaded rod, soak the hole with CA
glue, when dry thread the rod in. Drill a matching
1/8” [3mm] hole in the fuselage, this is only for alignment
and the rod should be a snug but easy fit. Once painted,
roughen the bonding surface and attach the fin using slow-
CA or “Goop” to the tail boom. Apply removeable “magic”
tape to the end of the stabilizer to the tail boom top and
bottom to ensure the stabilizers dry in the same position.
After marking, drill the 1/8” [3mm] hole in the fuselage. The end of the pre-finished stabilizer is bare balsa,
carefully soak the end with thin-CA or balsa filler to provide a hard bonding surface. On the fuselage, you have a
couple of choices, you can sand the bonding surface with fine-sandpaper to remove the paint and roughen the
fiberglass but be carefull not to remove any paint on the tailboom. Alternately, if you are bonding with slow-CA,
you can lightly sand the paint surface to remove the gloss finish and bond directly. Follow the taping procedure at
the end of the kit version until dry.
The horizontal stabilizers are attached to the tail boom by bonding the edge of the fin to the matching molded
protrusion on the tail boom. The threaded rods are only for alignment and do not significantly add to the strength
of the joint. Match the horizontal stabilizer to the mating molded section in the tail boom and draw a pencil line at
1/3~1/2 from the leading edge of the stabilizer.
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Horizontal
Stabilizer x 2
(unfinished)
[CN1075-3]
STEP 8 Windshield PreparationSTEP 8 Windshield Preparation
STEP 8 Windshield PreparationSTEP 8 Windshield Preparation
STEP 8 Windshield Preparation
Careful inspection will reveal a scribe line around the outside of
the each windshield half. Using a black marker, trace the line and
cut out both sides. It is simple to rough cut the parts first with
heavy shears or tin snips, this removes alot of the excess material
making the final trimming much easier with a sharp pair of scis-
sors. Curved hobby scissors are good but be careful, the hobby
scissors are really designed to cut small diameter radii and can be
difficult to cut in a straight line. To be extra careful, trim to within
1/16” [1.5mm] and sand the edges to get a perfect fit. For finish-
ing, using masking tape or liquid mask (common to R/C car
hobbyshops) mask off all areas except the outside 1/4” edge.
Using masking tape, cover the entire back side to avoid over-
spray while painting and apply paint to match the color planned
for the front body section. Let completely dry.
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Windshield
(unfinished)
[CN1075-4]
Flat Side
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STEP 9 Attach the Main Rotor HeadSTEP 9 Attach the Main Rotor Head
STEP 9 Attach the Main Rotor HeadSTEP 9 Attach the Main Rotor Head
STEP 9 Attach the Main Rotor Head
Now the rotor head assembly must be re-attached, insert the main
shaftthroughthe top bearing, the maststopperand insertthe
M3x16 Socket Cap screw below the main gear at a 45° angle.
Once through the auto-hub use a 2.5hex key to turn the bolt
while holding the M3 Locknut with pliers from the other side
at 45° degree angle. Access to the set screws in the mast
stopper is possible through the elevator lever assembly
(disconnect the lever to do this) but remember to pull up
on the main shaft first, tighten one set screw then remove
the second to apply threadlock. Finally, remove the first,
apply threadlock and tighten in place. If using the
slipper unit, access is possible between the starter
shaft and the side frames from the front.
STEP 10 Front NoseSTEP 10 Front Nose
STEP 10 Front NoseSTEP 10 Front Nose
STEP 10 Front Nose
The front nose is attached with four M3x8 Phillips Self Tapping screws from each side. Bonded to the inside are
small 3/8” plywood squares that the hold the screws in place. Take the time now to mount the gyro, receiver and
battery pack (wrapped in foam) inside the front nose if it wasn’t already done for test
flying. The location for the gyro is on the battery tray beside the collective
and throttle servos. Having completed the mechanics, lift the
helicopter by the flybar held perpendicular to the
length of the helicopter and continue to
movethebatterypackforwarduntil
balance is achieved. It maybe necessary
to construct an anchor, like a few
simple metal hooks bonded to the
inside of the nose to hold rubber
bands securing the battery pack. If
more weight is necessary, adding
weight is acceptable but be
cautious to the amount, if lead is
being used, bond it as far forward
as possible. See Step 14.
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Front Body
(unfinished)
[CN1075-1]
M3x8 Self Tapping
Screws x 8
[CN1075-5]
Mark the four screw locations
on the each side of the front
nose with a pencil. Using tape,
attach the front to the rear body and slowly drill each of the eight holes using a 3/32” [2.5mm] drill bit. Remove
the front nose and roughen one side of the eight plywood blocks and the area around the inside hole on the rear
body. Remember that the fiberglass parts are molded using Polyester resin and as a result, “Epoxy” type of glue
will not bond to the fiberglass. Any time two components are bonded to the fiberglass, slow to medium speed CA
(cyanoacrylate) adhesive is necessary. Using slow-CA bond each plywood block in place, clamp until dry. Redrill
each hole in the rear body through the plywood blocks and using one M3x8 Phillips Self Tapping screw, insert
and form the threads. After the fuselage is painted the front nose can be attached, remember to paint the screws to
match the color scheme.
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STEP 11 Bottom HatchSTEP 11 Bottom Hatch
STEP 11 Bottom HatchSTEP 11 Bottom Hatch
STEP 11 Bottom Hatch
STEP 12 Attaching the WindshieldsSTEP 12 Attaching the Windshields
STEP 12 Attaching the WindshieldsSTEP 12 Attaching the Windshields
STEP 12 Attaching the Windshields
If an exhaust diverter is to be used, install
before the bottom hatch is attached. The
bottom hatch is already cut to fit the landing
gear on the scale mechanics. Start by insert-
ing the rear cutouts and gently flexing the
ears to engage the rear struts, next grasp the
hatch with both hands, fingers on the side
edges and thumbs centered at the front and
gently bend the hatch in a “U” shape to allow
the front lip of the hatch to be inserted under
the edge of the front nose. Secure the hatch
using six M3x8 Phillips Self Tapping Screws.
Rear Body
with Bottom
Hatch
(unfinished)
[CN1075-2]
M3x8 Self
Tapping
Screws x 6
[CN1075-5]
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Mark the six screw locations on the hatch with a
pencil. Using tape, attach the hatch to the rear body
and slowly drill each of the six holes using a
3/32” [2.5mm] drill bit. Remove the hatch and roughen one side of the six plywood blocks and the area around
the inside hole on the rear body. Using slow-CA bond each plywood block in place, clamp until dry. Redrill each
hole in the rear body through the plywood blocks and using one M3x8 Phillips Self Tapping screw, insert and
form the threads. After the fuselage is painted the hatch can be attached, remember to paint the screws to match the
color scheme.
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Apply a thin 1/16” [1.5mm] bead of adhesive centered in the recessed
surface. Pick up the windshield by the edges only, remember “Goop” or
“Goop Fingerprints” cannot be removed if they touch a clear part.
Using single-use “Hobby grease syringes” are great and really
make this a simple task as the adhesive width and amount
can be easily controlled. Let dry for 24 hours. An
excellent alternative is to use “R/C 56 Canopy
Glue” from any airplane hobbyshop. This adhesive
remains white until fully curred in 24-48 hours
(slow but very good) but can be cleaned up using a
cloth and will not damage or scuff clear parts. When
dry, it is very strong. After bonding, apply “magic”
tape to secure the windshield halves until dry.
STEP 13 Fueling, Glow Plug Extension and Antenna RoutingSTEP 13 Fueling, Glow Plug Extension and Antenna Routing
STEP 13 Fueling, Glow Plug Extension and Antenna RoutingSTEP 13 Fueling, Glow Plug Extension and Antenna Routing
STEP 13 Fueling, Glow Plug Extension and Antenna Routing
If you have not already considered these items, now is the time. Most scale helicopter present new challenges to
simply change the glow plug when shrouded inside the fuselage. Century makes most items to solve these as
follows: CN2054 Universal Glow Wrench (check for compatibitity), CN2222 Remote Glow Plug Adapter -
absolutely essential for all model helicopters and CNT4444 In-line fueling valve with filter and filler - avoids
pulling the fuel line from the carburator to fuel the helicopter. The antenna wire needs to be routed in a path that
avoids the wire from touching any metal surfaces or servo wires. It is best that all the servo leads be collected and
secured on one side of the mechanics leaving the opposite side for the antenna. Whether you prefer the original
wire or use a “mini-whip” antenna, make sure that anytime the wire needs to cross any metal, use a short 1/2”
[12mm] length of fuel tubing to insulate the wire and attach with a tie wrap. Clean installations always work best.

11
Congratulations, you have a fine looking scale Twinstar helicopter kit.
The final work is in the balancing of the helicopter
before flying. With the main blades and tail
blades installed, pickup by the flybar with your
fingers and look to see how level the helicop-
ter hangs in the fore-aft direction. If neces-
sary, add nose weight to the to very front
of the fuselage. This can be glued inside
the front fuselage section infront of the
battery pack. Generally, 4-6 ounces is
the maximum weight that should be
added to the nose if you are using a
30 size engine.
Do not be concerned that the flybar
comes close to the top of the fuselage.
While working on the helicopter the
angle of the flybar to the main shaft in not
realistic and when in flight, the flybar will
not deflect half the distance possible.
Happy flying with your gorgeous Twinstar fuselage.
STEP 14 Final BalancingSTEP 14 Final Balancing
STEP 14 Final BalancingSTEP 14 Final Balancing
STEP 14 Final Balancing Twinstar Detail ManualTwinstar Detail Manual
Twinstar Detail ManualTwinstar Detail Manual
Twinstar Detail Manual
STEP 15 DecalsSTEP 15 Decals
STEP 15 DecalsSTEP 15 Decals
STEP 15 Decals
For best results, apply the decals after the paint work is started and all the colors have been applied but before any
clear topcoat has been applied. Following this method will allow the decals to be sandwiched in the finish for
greatestappearance andlongevity.
For the kit version, the next couple of pages describe the basic procedure to prepare and paint the fuselage.
Text, Logos &
Grill Decals
[CN1075-5]

12
This section is written to cover painting and detailing of fiberglass components using in Century’s scale helicopter
kits. Some included references may describe components of different kits, not exclusive to this detail instruction
manual.
Introduction to FiberglassIntroduction to Fiberglass
Introduction to FiberglassIntroduction to Fiberglass
Introduction to Fiberglass
When considering the strength compared to the space age canopies that are common on most pod and boom
helicopters there is no contest. This plastic material is virtually indestructible at the penalty of being virtually
un-paintable without specialized and expensive automotive primers and paints, there is also a very limited range
of color available. The reason you are reading this page is that you have come to your senses and wanted to fly
a model that looks and holds all the prestige of a real helicopter.
FlexibilityFlexibility
FlexibilityFlexibility
Flexibility
A wonderful attribute of fiberglass is in its flexibility. Century and Funkey take care and pride in craftsmanship
that goes into every fuselage. However, fiberglass parts will migrate (change shape) while inside the shipping
box. When two mating components are brought together and they do not align or mate, the culprit is a warped
part. Many become upset and wish to lay blame but dealing with this is very simple when explained a simple
procedure. Using a heat gun set at the high setting at a distance of 1-2 feet away, evenly heat the warped part until
the outside surface is hot to the touch and the part has become pliable (flexible). Using adhesive tape, mate the
two fiberglass parts together and let both parts sit until both parts have reached room temperature. Remove the
tape and now both parts are stable and match one another. In some instances, depending on the location of the
warp, the part may need to be held in an overextended position to achieve the proper shape when the part is
finished.
Working with FiberglassWorking with Fiberglass
Working with FiberglassWorking with Fiberglass
Working with Fiberglass
Difficult to work with, we disagree. Fiberglass is easier to repair than you think. Using today’s CA type of
adhesives, a severe crack in a fuselage can be simply fixed and the repaired section is much stronger than in its
original state. Add touchup paint and no one would ever know it had been damaged. There is a limit to this type
of thinking where purchasing the replacement fiberglass part is simply cheaper and less work than performing
majorreconstructivesurgery.
The Paint Job.The Paint Job.
The Paint Job.The Paint Job.
The Paint Job.
There is no magic to a good paint job, the true secret is time, patience and common sense. A beginner who
thinks that they can throw paint onto a fuselage Friday night before flying on Sunday is dreaming, the helicopter
would be flyable but even that is a stretch. The average beginner will spend the better part of a month to apply
a good clean paint job.
Preparing the fuselage for painting.Preparing the fuselage for painting.
Preparing the fuselage for painting.Preparing the fuselage for painting.
Preparing the fuselage for painting.
After opening the kit version of the fuselage, examine all the fiberglass components to see where work needs to
be done to allow a simple "bring up" of the fuselage. "Bring up" describes the necessary steps to complete all
the jobs in order to start priming the fiberglass parts. Typical work that is done at this stage is rough sanding on
seams and jointed components, filling of surface imperfections, adding panel lines and rivets, cutting required
holes and preparation for priming.
1. Start by thoroughly washing all fiberglass parts in mild detergent and warm water, this will remove any
residue remaining from the molding process. Next wipe down all the parts with Acetone (from the hardware
store). The Acetone will remove all traces of oil or grease that will affect the adhesion of two fiberglass parts or
between the paint and the fiberglass. Now using fine steel wool or an abrasive pad commonly used for scrub-
bing dishes, scuff all surfaces that will be joined or receiving paint. What is important to note here is that we
are breaking through the topmost resin surface and creating the best surface for adhesive or primer to adhere to.
Section Three: Preparing and painting the kit version.Section Three: Preparing and painting the kit version.
Section Three: Preparing and painting the kit version.Section Three: Preparing and painting the kit version.
Section Three: Preparing and painting the kit version.

13
The prepared finish will have very fine score marks usually seen when the part is held to the light at a slight angle.
2. This is the time to rough sand any accessories or small parts, using the 320 grit sandpaper, that will be as-
sembled and attached at different positions on the fuselage. These can be marking lights, engine exhausts, scale
fuel tanks, horizontal and vertical stabilizers, guns, antenna or any scale details being bonded to the fuselage.
These accessories should be test assembled to make sure that all parts are prepared, and you will be able to see any
problems that may arise in trying to paint these parts. Some thought should be put into how to hold the part as it is
being painted. Go ahead and bond these parts at this time using the slow CA glue. A quick note on adhesives, as
the fuselage resin is polyester, do not use any regular 5-30 minute epoxies to bonddo not use any regular 5-30 minute epoxies to bond
do not use any regular 5-30 minute epoxies to bonddo not use any regular 5-30 minute epoxies to bond
do not use any regular 5-30 minute epoxies to bond two fiberglass components
together. Stabilit is specially formulated for this purpose and excellent for fillets. Epoxy and polyester will not
bond properly to one another, but epoxy is good to bond unlike substances like wood or metal to themselves or
otherparts.
3. Once the detail parts have been built into sub assemblies, they are ready to paint, use a filler in sections that
have gaps or slight surface imperfections, occasionally there are voids (air bubbles in the resin) that occur near the
surface that need to be filled. There are alot of good fiberglass fillers on the market, it is best to check with your
local hobby shop to get a recommended product. Try to stay away from porous fillers designed for wood as they
will shrink and are not a good choice for large areas.
4. Most major windows and accessory holes have been precut by Century, leaving only those that have a user
dependency like the type of exhaust system used on the helicopter or the exact exit position for the cooling fan
shroud. For these fuselages that have been explicitly designed for the Century’s scale mechanics, almost all of
these concerns have been considered and finished at the factory. This leaves the hole for the exhaust, if you are
using the recommended scale muffler (CN3058 .32-.38 or CN3059 .46-.50) then these dimensions have been
included on a template in the Scale Mechanics Manual for the 30 size engine, the 46-50 requires a slight adjust-
ment.
4a. When making cutouts or holes in the surface of the fiberglass the best procedure is to drill a pilot hole using a
1/16" drill bit at corners or along a curve. Start with a permanent marker to draw the opening or window. The
pilot holes serve to avoid leaving sharp corners which given the nature of a model helicopter will be the focal
point for stress cracking originating from corners. Once the holes have been made, use the moto-tool for all other
roughing cuts. The cut off wheel is the best for straight lines and either the sanding drum or the curved stone is
used for smoothing edges. If the cut out is a window, do not use the moto-tool for the final work. Switch to a
sanding blocks, square blocks of various sizes for straight edges and round dowels for rounded corners.
4b. In the case of the exhaust opening, it should end up being 1/8" larger across the outside diameter of the
exhaust pipe that extends below the bottom of the fuselage. After drawing the circle, use grinding stone and move
in small circles until the hole is at the size wanted.
5. Priming the fuselage accomplishes two tasks: firstly, the primer paint is designed to aggressively adhere to
the surface being painted and provide the best surface for the colored paint to adhere to; secondly, all surface
imperfections will become visible. Depending on the particular imperfection, light sanding with number 600 or
800 sand paper and the second priming will take care of 90% of the highly visible problems. The remaining
10% need to be filled, let dry, sanded again and then sprayed with the second coat of primer. The primer pro-
cess will be repeated until the surface is as perfect as your patience and time permit.
6. Select your paint color and follow the directions on the particular brand of paint being used as each manufac-
turerhasdifferentrequirements.

Century Helicopter Products
523 Sinclair Frontage Rd., Milpitas, CA 95035 USA
Fax:[phone]
www.centuryheli.com email: [e-mail]
CommonReplacementParts:
CN1075-1 Front Body(unpainted) ........................................................................................... 1
CN1075-2 Rear Body with Bottom Hatch (unpainted) ............................................................. 1
CN1075-3 Tail Fin Set(unpainted) ........................................................................................... 1
CN1075-4 Windshield (unfinished) ........................................................................................... 1
CN1075-5 Hardware Set & Decal (logos & text only) .............................................................. 1
CN1075-6 Detail & Scale Mechanics Manual........................................................................... 1
CN2322 ARF Main Rotor Blades (550mm) Pair ................................................................... 1
HI3122 LandingStruts(Twinstar) ........................................................................................ 2
HW3123 LandingSkids(Twinstar) ........................................................................................ 2
HW3062R Tail boom (Red anodized is for Twinstar & Long Ranger)...................................... 1
HW3064C Tail Pitch Control Rod Set need trim 10 or 20mm (for all) ...................................... 1
OptionalParts:
CN0427 Hex one way start extension .................................................................................... 1
CN2054 Universal Glow Plug Wrench.................................................................................. 1
CN2222 Remote Glow Plug Connector................................................................................. 1
CN3014 Exhaust Diverter 30 size, 45° Degree ...................................................................... 1
CN3015 Exhaust Diverter 40-60 size, 90° Degree................................................................. 1
CN3016 Exhaust Diverter 40-60 size, 45° Degree................................................................. 1
CN3058 32-38 Scale Muffler (optional)................................................................................. 1
CN3059 46-50 Scale Muffler (optional)................................................................................. 1
CNT4444 Branch Valve w/Filter & Filling Nozzle Set............................................................. 1
CN1075-1
FrontBody
(unpainted)
CN1075-2 Rear Body
with Bottom Hatch
(unpainted)
CN1075-3 Tail Fin Set
(unpainted)
CN1075-4
Windshield
(unfinished)
CN2322 ARF
Main Blade
HW3123 Landing Skids
HI3122 Landing Struts
HW3062R Tail
Boom (Red)
Twinstar Replacement PartsTwinstar Replacement Parts
Twinstar Replacement PartsTwinstar Replacement Parts
Twinstar Replacement Parts
CN1075-5 Hardware Set
& Decal (not pictured)