Seagull Models SEA12 User manual

Specifications
Wingspan---------------------------------------60.63in, 1540mm.
Wing area--------------------------------610 sq.in, 37.04sq.dm.
Fuselage length--------------------------------43.7in, 1110mm.
Approximate flying weight---------5.5-5.95lbs, 2500-2700g.
Recommended engine size---------.40-.58 cu.in. 2-stroke.
----------------------------------------------.50-.72 cu.in. 4-stroke.
Recommended R/C-----------------------4 channel minimum.
Flying skill level-------------------------Intermediate/advanced.
Kit features.
• Ready-made—minimalassembly&finishingrequired.
• Factory-installedpushrods.
• Comprehensivehardwarepackincludingwheels,tank,
undercarriage & spinner.
• Photo-illustratedstep-by-stepAssemblyManual.
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ASSEMBLASSEMBL
ASSEMBLASSEMBL
ASSEMBLY MANUY MANU
Y MANUY MANU
Y MANUALAL
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Additionalitemsrequired.
Engine.
4 Channel or greater Radio Control system.
Glues.
Tools.
Starting Equipment.
MadeinVietnam.
PC-9 semi Scale ARF Model
MS:12

INTRODUCTION.
Thank you for choosing the PC-9 ARTF by SG MODELS. The PC-9 was designed with the
intermediate/advanced sport flyer in mind. It is a low-wing scale aeroplane which is easy to fly and
quicktoassemble.Theairframeisconventionallybuiltusingbalsa,plywoodandveneertomake it
strongerthantheaverageARTF,yetthedesignallowstheaeroplanetobekeptlight.Youwillfind
that most of the work has been done for you already. The pushrods are pre-made to the correct
lengths, the motor mount has been fitted and the hinges are pre-installed and pinned for security.
Flying the PC-9 is simply a joy.
This instruction manual is designed to help you build a great flying aeroplane. Please read this
manualthoroughly before starting assemblyof your PC-9 . Use the partslisting below to identify all
parts.
WARNING.
Pleasebeawarethatthisaeroplaneisnotatoyandifassembledorusedincorrectlyitiscapable
of causing injury to people or property. WHEN YOU FLY THIS AEROPLANE YOU ASSUME ALL
RISK&RESPONSIBILITY.
If you are inexperienced with basic R/C flight we strongly recommend you contact your R/C
supplierandjoinyourlocalR/CModelFlyingClub.R/CModelFlyingClubsofferavarietyoftraining
proceduresdesignedtohelp thenewpilotonhiswayto successful R/Cflight.Theywillalsobeable
to advise on any insurance and safety regulations that may apply.
ADDITIONAL ITEMS REQUIRED.
* .40-.58 2-stroke engine.
* .50-.72 4-stroke engine.
* 4-channel radio with five servos.
* Glow plug to suit engine.
* Propeller to suit engine.
* Protective foam rubber for radio
system.
* Silicone fuel line.
* Stick-on weights for balance
(If necessary).
TOOLS & SUPPLIES NEEDED.
* Thick cyanoacrylate glue.
* 30 minute epoxy.
* 6 minute epoxy.
* Hand or electric drill.
* Assorted drill bits.
*Modellingknife.
* Straight edge ruler.
* 2mm ball driver.
* Phillips head screwdriver.
* 220 grit sandpaper.
* 90° square or builder’s triangle.
* Wire cutters.
* Masking tape & T-pins.
* Thread-lock / Paper towels.
PARTS LISTING.
FUSELAGE ASSEMBLY
* (1) Fuselage.
* (1) Pre-installed throttle pushrod &
tube.
* (1) Pre-installed servo tray.
WING ASSEMBLY
* (1) Right wing half with pre-
installedaileron.
* (1) Left wing half with pre-installed
aileron.
* (1) Aluminium wing dihedral
brace.
TAIL SECTION ASSEMBLY
* (1) Vertical stabilizer with pre-
installedrudder.
* (1) Horizontal stabilizer with pre-
installedelevatorhalves.

3
NOTE:To avoid scratching your new aero-
plane we suggest that you cover
your workbench with an old towel.
Keepacoupleofjarsorbowlshandy
toholdthesmallpartsafteryouopen
the bags.
Please trial fit all parts. Make sure
you have the correct parts and that
they fit and are aligned properly be-
fore gluing! This will ensure proper
assemblyasthePC-9 is made from
natural materials and minor adjust-
ments may have to be made.
The paint and plastic parts used in
thiskit are fuel proof. However,they
arenottolerantofmanyharshchemi-
cals including the following: paint
thinner, cyano-acrylate glue accel-
erator,cyanoacrylategluede-bonder
andacetone.Donotletthesechemi-
calscomeincontactwiththecolours
onthecoveringandtheplasticparts.
4)Deflect the aileron and completely
saturate each hinge with thin C/A glue. The
aileronsfrontsurfaceshouldlightlycontactthe
wing during this procedure. Ideally, when the
The control surfaces, including the
ailerons, elevators, and rudder, are
prehinged with hinges installed, but the
hinges are not glued in place. It is
imperativethat you properlyadherethe
hingesin place perthe steps that follow
using a high-quality thin C/A glue.
1)Carefullyremovethe aileron from one of
thewingpanels.Notethepositionofthehinges.
2)Removeeachhingefromthewingpanel
and aileron and place a T-pin in the center of
each hinge. Slide each hinge into the aileron
untiltheT-pin is snugagainst the aileron.This
will help ensure an equal amount of hinge is
oneithersideof the hingelinewhentheaileron
is mounted to the wing panel.
HINGING THE AILERONS.
Note:
3) Slide the aileron on the wing panel until
there is only a slight gap. The hinge is now
centered on the wing panel and aileron.
Remove the T-pins and snug the aileron
against the wing panel.A gap of 1/64” or less
shouldbemaintained between thewingpanel
andaileron.
Hinge.
T-pin.
T-pin.

PC-9 Instruction Manual.
4
8)After both ailerons aresecurely hinged,
firmly grasp the wing panel and aileron to
make sure the hinges are securely glued and
cannot be pulled out. Do this by carefully
applying medium pressure, trying to separate
the aileron from the wing panel. Use caution
not to crush the wing structure.
7) Repeat this process with the other wing
panel, securely hinging the aileron in place.
5)Turnthewingpanelover and deflect the
aileron in the opposite direction from the
opposite side. Apply thin C/A glue to each
hinge,makingsure thattheC/Apenetratesinto
both the aileron and wing panel.
6) Using C/A remover/debonder and a
papertowel,remove any excess C/Agluethat
may have accumulated on the wing or in the
aileronhinge area.
The hinge is constructed of a special
material that allows the C/A to wick or
penetrateanddistributethroughoutthe
hinge, securely bonding it to the wood
structureofthe wing panel andaileron.
hinges are glued in place, a 1/64” gap or less
will be maintained throughout the lengh of the
aileron to the wing panel hinge line.
Note:
C/Aglue.
Work the aileron up and down several
times to “work in” the hinges and check
for proper movement.
Glue the elevator hinges in place using the
same techniques used to hinge the ailerons.
HINGING THE ELEVATOR.
Note:
C/Aglue.
C/Aglue.
Apply epoxy glue.
Metalwire.

5
WING ASSEMBLY.
1) Locatethewingdihedralbrace.Usinga
ruler,locateitscentre and draw averticalline.
We highly recommend using 30 minute
epoxy as it is stronger and provides more
working time, allowing the builder to properly
align the parts. Using fast cure epoxy when
joiningthewinghalves could result in theglue
drying before the wing halves are aligned
properlywhichmayresultinfailureofthewing
centre section during flight.
HINGING THE RUDDER.
Glue the elevator hinges in place using the
same techniques used to hinge the ailerons.
2) Testfitthedihedralbraceintoeachwing
half. The brace should slide in easily up to the
centreline that you drew.
Carefully slide the two wing halves together
and firmly press them together, allowing the
excess epoxy to run out. There should not be
any gap in the wing halves. Use rubbing
alcohol and a paper tower to clean up any
excess epoxy.
Apply masking tape at the wing join to hold
the wing halves together securely.
Dihedral brace.
Centreline.
3) Removethe bracewhen satisfied with
its fit in each wing half. Coat dihedral brace
with30 minute epoxy.Next, pour someepoxy
into the dihedral box in one wing panel.
4) Peel off the backing from the self
adhesive covering strip. Apply the strip to the
centre section of the wing starting from the
bottomtrailingedge.Wrapthestripalltheway
aroundthewinguntilit meets the trailingedge
again. Trim off any excess strip.
Epoxy.
Maskingtape.

PC-9 Instruction Manual.
6
Small weight.
Thread.
INSTALLING THE AILERON SERVOS.
1) Installtherubbergrommetsandbrass
collets onto the aileron servo. Test fit the
servo into the aileron servo mount.
Small
weight.
Servo.
Thread.
Remove covering.
Glueattached.
3) Attach servo lead to the aileron servo.
Attach the string to the servo lead and care-
fullythread it though the wing.Once you have
thread the lead throught the wing, remove the
string so it can use for the other servo lead.
Because the size of servos differ, you
may need to adjust the size of the precut
opening in the mount. The notch in the sides
of the mount allow the servo lead to pass
through.
Secure the servos with the screws pro-
vided from your radio system.
2) Using a small weight (Weighted fuel
pick-upworkswell)andthread,feedthestring
through the wing as indicated.
Thread.
Small weight.
Thread.

7
2mm X 20mm.
ControlHorn.
MountingScrews. Mounting Plate.
4) Tape the servo lead to the wing to pre-
vent it from falling back into the wing.
 5) Reinstall the servointo the servomount
and secure the servo inplace using the wood
screws provided with you radio system.
Thread.
Plastic tape.
2) Locate the two nylon control horns,
two nylon control horn backplates and four
machine screws.
3)Positiontheaileronhornonthebottom
side of aileron. The clevis attachment holes
should be positioned over the hinge line.
Pen.
Straight line.
Repeat the procedure for the other wing
half.
1) Using a ruler & pen to draw a straight
line as below picture.
AILERON LINKAGE.

PC-9 Instruction Manual.
8
Cut.
4) Using a 1mm drill bit and the control
horns as a guide, drill the mounting holes
through the aileron halves.
6) Thread one nylon adjustable control
hornontoeachaileroncontrolrod. Threadthe
horns on until they are flush with the ends of
the control rods.
5)Mountthecontrolhornsbyinsertingthe
screws through the control horn bases and
aileron halves, then into the mounting
backplates. Do not overtighten the screws or
the backplates may crush the wood.
7) With the aileron servo centered and
the aileron even with the trailing edge of the
wingattachtheclevistothecontrol horn. Mark
the control wire where it crosses the servo
arm hole.
8) Make a 90-degree bend at the mark
andcutoffthe excess wire leaving10mmpast
thebend.
INSTALLING THE MAIN GEAR WIRES.
1) Using a modeling knife, remove the
covering from over the two main gear mount-
ing slots located in the bottom of the wing.
9) Connect the linkage as shown and
secure the control wire with a wire keeper.
Repeat the procedure for the other
aileron servo.
2) Insert the 90º bend of one main gear
wire into the predrilled hole in one mounting
slot.
Remove covering.
Pen.

9
6) Reinstall the gear wire and install the
straps using the four 3mm x 12mm wood
screws. Tighten the screws completely to se-
cure the gear wire in place.
7) Slide one wheel collar with 3mm x
6mm set screw onto each axle. Push the
wheel collars on as far as they will go and
tighten the set screws.
Be careful not to overtighten the set
screws. Overtightening may cause the
threads to strip.
3) The landing gear wire is held in place
using two nylon landing gear straps and four
3mm x 12mm wood screws.
The straps should be located equal dis-
tance from the inside and outside ends
ofthewire.
4)Usingthetwo landing gear strapsasa
guide, mark the locations of the four 3mm x
12mm mounting screws onto the wing sur-
face.
5) Remove the two straps and the gear
wire. Drill four 3/32” pilot holes into the wing
for the wood screws.
Be careful do not to drill through the
top of the wing!
8) Slide one 60mm diameter wheel onto
eachaxleandpushthemupagainstthewheel
collars. Slidetheremaining wheel collars with
3mm x 6mm set screws onto the axles. Push
them up against the wheels and tighten the
set screws. The wheels should spin free and
notbindinany way. Ifthey do bind, loosen the
setscrewsintheouterwheelcollarsandmove
the collars out a small amount. Retighten the
set screws.
NOSE GEAR INSTALLATION.
Adjust the nose gear steering arm until the
arm is parallel with the fire wall.
Installing steering arm as below.
Steering arm.

PC-9 Instruction Manual.
10
Install the pushrod wire as shown.
Adjustable
Connector.
Slide one 60mm diameter wheel collar onto
the axle and tighten. Slide the nose wheel on
and push it up against the wheel collar. Slide
the remaining wheel collar on and push it up
against the wheel and tighten the set screw.
The wheels should spin free and not bind in
any way.
INSTALLING THE NOSE GEAR WHEEL.
1) Using a modeling knife, carefully cut
offthe rearportionofoneofthetwonylontubes
leaving 1/2” protruding from the rear of the
stopper. This will be the fuel pick up tube.
2) Usinga modeling knife, cutone length
ofsilicon fuel line (notincluded) to 2-1/4” long.
Connect one end of the line to the weighted
fuel pickup and the other end to the nylon
pickup tube.
3) Carefully bend the second nylon tube
up at a 45º angle. This tube is the vent tube.
INSTALLING THE STOPPERASSEMBLY.
FUEL TANK.

11
4) Carefully heat the vent tube using a
heat gun or lighter to permanently set the
angle of the tube.
When the stopper assembly is installed in
the tank, the top of the vent tube should rest
justbelowthetopsurfaceofthetank. Itshould
not touch the top of the tank.
5) Test fit the stopper assembly into the
tank. It may be necessary to remove some of
the flashing around the tank opening using a
modeling knife. If flashing is present, make
sure none falls into the tank.
6) With the stopper assembly in place,
the weighted pickup should rest about 3/8”
awayfromtherearofthetank and move freely
insidethetank. Thetop oftheventtubeshould
rest just below the top of the tank. It should
not touch the top of the tank.
7) When satisfied with the alignment of
thestopperassemblytighten the3mmx20mm
machine screw until the rubber stopper ex-
pands and seals the tank opening. Do not
overtighten the assembly as this could cause
the tank to split.
INSTALLING THE FUEL TANK.
Vent tube. FuelPickup
Tube.
FuelFill Tube.

PC-9 Instruction Manual.
12
MOUNTING THE ENGINE.
 1) Trialfit your engine on the motor mount.
The engine should be positioned so there is
ample clearance in the cowling for spinner
backplate mounted to the prop drive shaft.
2) Marking 4 points on the plastic motor
mount.
 3) Screw 4 pilot holes with 2.5 mm diam-
eter
Fuel fill tube.
Fuelpickup
tube.
Vent tube.
4) Secureyourengineon themotormount
by mounting with 4 machine screws.
2.5mm.
3mm X 25mm.
 5) Attach the Z-Bend in the pushrod wire
to the throttle arm on the carburetor. You will
need to remove the throttle arm from the car-
buretor to be able to attach the Z-bend. When
complete, reattach the throttle arm to the car-
buretor.
Pushrod wire.
11cm.

ELECTRIC POWER CONVERSION.
1) Locate the items necessary to install
the electric power conversion included
with your model.
2) Recommend the items necessary to in-
stall the electric power conversion parts
included with your model.
- Motor: 46 - 925 Watts
- Propeller: 12x8 ~ 14x10
- ESC: 60A
- 4S- 5S Lipo
3) Attach the electric motor box to the
rewall suitable with the cross lines
drawn on the electric motor box and re-
wall. Using epoxy and balsa stick to se-
cure the motor box to the rewall. Please
see pictures below.
4) Attach the motor to the front of the
electric motor box using four 4mm blind
nut, four M3x15mm hex head bolts to se-
cure the motor. Please see picture shown.
4 mm
13

Instruction Manual.
.
M3x15mm
11cm
Epoxy
14

Speed control.
Battery.
M3x15mm
15
Air exit hole.

Trim and cut.
COWLING.
1) Slide the fiberglass cowl over the en-
gineandlineupthe back edge of the cowlwith
the marks you made on the fuselage
Trim and cut.
4) Remove the cowl. Using a 5/64” drill
bit, enlarge the holes in only the four cowl
blocks.
5) Usinga1/8” drillbit.Enlargingtheholes
through the cowl will prevent the fiberglass
from splitting when the mounting screws are
installed.
6) Slide the cowl back over the engine and
secure it in place using four 3mm x 12mm
wood screws. See picture below.
Because of the diameter of the cowl, it
may be necessary to use a needle valve ex-
tensionforthehighspeedneedlevalve. Make
thisout of sufficientlength1.5mm wire andin-
stall it into the end of the needle valve. Se-
cure the wire in place by tightening the set
screw in the side of the needle valve.
7) Installthemufflerand mufflerextension
onto the engine and make the cutout in the
cowl for muffler clearance. Connect the fuel
and pressure lines to the carburetor, muffler
andfuel filler valve.
2) While keeping the back edge of the
cowl flush with the marks, align the front of
thecowlwiththecrankshaftof the engine. The
front of the cowl should be positioned so the
crankshaft is in the middle of the cowl open-
ing. Holdthe cowl firmlyin place using pieces
of masking tape.
3) While holding the cowl firmly in posi-
tion,drillfour1/16”pilotholes through both the
cowl and through the mounting blocks.
16

PC-9 Instruction Manual.
INSTALLINGTHESPINNER.
Install the spinner backplate, propeller
andspinner cone. The spinner coneis held in
place using two 3mm x 12mm wood screws.
The propeller should not touch any part
of the spinner cone. If it does, use a
sharp modeling knife and carefully trim away
the spinner cone where the propeller comes
in contact with it.
1) Install the switch into the precut hole
in the servo tray, in the fuselage, from the bot-
tom. Use the two screws provided with the
switch to secure it in place. Drill two 3/32”
holes through the tray for the screws to pass
through.
2) Using a 3/32” drill bit, drill a hole
through the side of the fuselage, opposite the
muffler, even with the switch.
INSTALLING THE SWITCH.
3) Make a push-pull lever out of scrap
wire. Attach the wire to the switch lever and
route the wire out the side of the fuselage,
through the hole you drilled.
Some switches come with a hole drilled
through the switch tab for this very pur-
pose. If your switch does not, remove the
switchanddrilla3/32”holethroughthemiddle
of the switch tab.
17

1) Install the rubber grommets and brass
collets onto the elevator, rudder and throttle
servos. Testfittheservos into thepreinstalled
servo tray. Because the size of servos dif-
fer, you may need to adjust the size of the
precut openings in the tray.
2) Position the servos into the servo tray
with the output shafts orientated as shown
below. Drill 1/16” pilot holes through the tray
for each of the mounting screws.
INSTALLINGTHEFUSELAGESERVOS.
Secure the servos with the screws pro-
vided from your radio system.
1) Using a ruler and a pen, locate the
centerlineofthehorizontalstabilizer,atthetrail-
ing edge, and place a mark. Use a triangle
and extend this mark, from back to front,
across the top of the stabilizer. Also extend
thismark down theback of the trailingedge of
the stabilizer.
ALIGNINGTHE HORIZONTALSTABILIZER.
2) Using a modeling knife, carefully re-
move the covering from over the vertical sta-
bilizermounting slot inthetop of thefuselage.
4) When you are satisfied with the align-
ment, hold the stabilizer in place with T- pins
or masking tape, but do not glue at this time.
MOUNTINGTHEHORIZONTALSTABILIZER.
1) With the stabilizer held firmly in place,
use a pen and draw lines onto the stabilizer
where it and the fuselage sides meet. Do this
on both the right and left sides and top and
bottom of the stabilizer.
2) Remove thestabilizer. Usingthe lines
youjust drew asaguide, carefully removethe
covering from between them using a model-
ingknife.
When cutting through the covering to re-
move it, cut with only enough pressure
toonly cut through the coveringitself. Cutting
into the balsa structure may weaken it.
Removecovering.
3) Using a modeling knife, carefully re-
move the covering that overlaps the stabilizer
mounting platform sides in the fuselage. Re-
move the covering from both the top and the
bottom of the platform sides.
4) When you are sure that everything is
aligned correctly, mix up a generous amount
of 30 Minute Epoxy. Apply a thin layer to the
topandbottom of thestabilizermounting area
and to the stabilizer mounting platform sides
Draw center line.
Pen.
3) Slidethestabilizerintoplaceinthe pre-
cut slot in the rear of the fuselage. The stabi-
lizer should be pushed firmly against the front
of the slot.
Throttle.
Elevator.
Rudder. Switch.
18

PC-9 Instruction Manual.
1) Using a modeling knife, remove the
covering from over the precut hinge slot cut
intothelowerrearportionofthe fuselage. This
slot accepts the lower rudder hinge.
VERTICAL STABILIZER
INSTALLATION.
Hingeslot.
5) After the epoxy has fully cured, re-
move the masking tape orT-pins used to hold
the stabilizer in place. Carefully inspect the
glue joints. Use more epoxy to fill in any gaps
that may exist that were not filled previously
and clean up the excess using a paper towel
and rubbing alcohol.
in the fuselage. Slide the stabilizer in place
and realign. Double check all of your mea-
surementsoncemorebefore the epoxy cures.
HoldthestabilizerinplacewithT-pins or mask-
ing tape and remove any excess epoxy using
a paper towel and rubbing alcohol.
2) Slidethe vertical stabilizerintothe slot
in the top of the fuselage. The rear edge of
thestabilizer shouldbeflushwiththerearedge
of the fuselage and the lower rudder hinge
should engage the precut hinge slot in the
lowerfuselage. The bottom edgeofthe stabi-
lizer should also be firmly pushed against the
top of the horizontal stabilizer.
3) While holding the vertical stabilizer
firmly in place, use a pen and draw a line on
each side of the vertical stabilizer where it
meets the top of the fuselage.
When cutting through the covering to re-
moveit, cutwith only enough pressure toonly
cut through the covering itself. Cutting into
the balsa structure may weaken it.
4) Remove the stabilizer. Using a mod-
elling knife, remove the covering from below
the lines you drew. Also remove the covering
from the bottom edge of the stabilizer and the
bottomandtopedgesof the filler block. Leave
the covering in place on the sides of the filler
block.
Pen.
19

top edges of the filler block and to the lower
hinge also. Set the stabilizer in place and re-
align. Double check all of your measurements
once more before the epoxy cures. Hold the
stabilizer in place with T-pins or masking tape
and remove any excess epoxy using a paper
towel and rubbing alcohol. Allow the epoxy to
fully cure before proceeding
CONTROL HORN INSTALLATION.
1) Locatethetwonyloncontrolhorns, two
nylon control horn backplates and four 2 x
20mm machine screws.
2) Position the two elevator horns on the
bottom side of each elevator. The clevis at-
tach- ment holes should be positioned over
thehinge line.
2mm X 20mm.
4) Mount the control horns by inserting
thescrewsthroughthecontrolhornbasesand
eleva- tor halves, then into the mounting
backplates. Do not overtighten the screws or
the backplates may crush the wood.
5)Positionthe rudder controlhornon the
left side of the airplane.
6)Installtherudder control horn usingthe
same method as with the elevator control
horns.
3) Using a 5/64" drill bit and the control
horns as a guide, drill the mounting holes
through the elevator halves.
ControlHorn.
MountingScrews. Mounting Plate.
5) Slide the vertical stabilizer back in
place. Using a triangle, check to ensure that
thevertical stabilizer is aligned90º to thehori-
zontal stabilizer.
6) When you are sure that everything is
alignedcorrectly,mix upagenerousamountof
Flash30 MinuteEpoxy. Applyathinlayertothe
mounting slot in the top of the fuselage and to
the sides and bottom of the vertical stabilizer
mountingarea. Applyepoxytothebottomand.
90º
Vertical
Stabilizer.
Horizontal
Stabilizer.
Remove covering.
Left side.
20