Seagull Models JUMPER 25 User manual

Arising Star InstructionManual
Made in Vietnam.
• Ready-made—minimalassembly&finishingrequired.
• Comprensivehardwarepack includingwheels,tank,parts,undercarriage&
spinner.
• Photo-illustrated step-by-step AssemblyManual.
Specifications:
Wingspan _________________________55 in, 139cm.
Wing area ___________________ 480 sq.in, 31 sq.dm.
Length____________________________41 in, 103cm.
Approximate flying weight______ 4.9-5.5 lbs, 2.2-2.5kg.
Recommended engine size ___.25-.32 cu.in 2-stroke.
Radio System required 4 channel with 4 servo.
Flying skill level --------------------- High wingTrainer.
INSTRUCTION MANUAL
MS:15.
Kit features.
Additionalitemsrequired.
Engine.
4 Channel or greater Radio Control system.
Glues.
Tools.
Starting Equipment.

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JUMPER 25. Instruction Manual.
INTRODUCTION.
Thank you for choosing the JUMPER 25 ARTF by SEAGULL MODELS. The JUMPER 25 was
designed with the intermediate/advanced sport flyer in mind. It is a High-wing aeroplane which is
easytoflyandquicktoassemble.Theairframeisconventionallybuiltusingbalsa,plywoodtomake
itstrongerthantheaverage ARTF, yet the designallowstheaeroplanetobekeptlight.Youwill find
that most of the work has been done for you already. Flying the JUMPER 25 is simply a joy.
This instruction manual is designed to help you build a great flying aeroplane. Please read this
manual thoroughly before starting assembly of your JUMPER 25. Use the parts listing below to
identify all parts.
WARNING.
Please be aware that this aeroplane is not a toy and if assembled or used incorrectly it is capable
of causing injury to people or property. WHEN YOU FLY THIS AEROPLANE YOU ASSUME ALL
RISK&RESPONSIBILITY.
IfyouareinexperiencedwithbasicR/CflightwestronglyrecommendyoucontactyourR/Csupplier
and join your local R/C Model Flying Club. R/C Model Flying Clubs offer a variety of training
proceduresdesignedto helpthenewpilotonhis waytosuccessfulR/Cflight. Theywillalsobeable
to advise on any insurance and safety regulations that may apply.
ADDITIONAL ITEMS REQUIRED.
.25-.32 cu. in 2-stroke engine.
4-channel radio with four digital
servos.
Glow plug to suit engine.
Propeller to suit engine.
Protective foam rubber for radio
system.
Siliconefuel line.
TOOLS & SUPPLIES NEEDED.
Thick cyanoacrylate glue.
30 minute epoxy.
5 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 servo tray.
(1) Pre-installed motor mount.
(1) Pre-installed rudder pushrod.
(1) Pre-installed elevator pushrod.
WING ASSEMBLY
(1) Right wing haft/ aileron.
(1) Left wing half/ aileron.
(1) Plywood wing dihedral brace.
(1) Covering strip for centre section
joint.
TAIL SECTION ASSEMBLY
(1) Horizontal stabilizer/ elevator
halves.
(1) Rudder/ halves.
Some more parts.
HARDWAREPACK
COWLING
Landing gear .....

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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
assembly as the JUMPER 25 is
made from natural materials and
minor adjustments may have to be
made.
The paint and plastic parts used in
thiskit are fuelproof. However,they
arenottolerantofmanyharshchemi-
cals including the following: paint
thinner, cyano-acrylate glue accel-
erator,cyanoacrylategluede-bonder
andacetone.Donotletthesechemi-
calscomeincontactwiththecolours
onthecoveringandtheplasticparts.
Maskingtape.
Centreline.
Expoxy.
2) Remove the brace when satisfied with
its fit ineach wing half. Coat both sides of one
halfofthedihedralbracewith30minuteepoxy.
Next,poursomeepoxyintothedihedralboxin
one wing panel. Make sure you cover the top
andbottomaswellasthesidesofthedihedral
brace. Use enough epoxy to fill any gaps.
 1)Testfitthewingtubeintoeachwinghalf.
The brace should slide in easily up to the
centreline that you drew.If not, use 220 grit
sandpaper with a sanding block and sand
down the edges and ends of the brace until it
fits properly.
WING ASSEMBLY.
NOTE: We highly recommend using 30
minute epoxy as it is stronger and provides
more working time, allowing the builder to
properlyaligntheparts.Usingfastcureepoxy
whenjoiningthewinghalvescouldresultinthe
gluedryingbeforethewinghalvesarealigned
properlywhichmayresultinfailureofthewing
centre section during flight.
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.

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JUMPER 25. Instruction Manual.
✔ ) Carefully apply masking tape around
thetopandbottom edgeoftherootribofeach
winghalftoprotectthemfromdamagecaused
byepoxy.
1) Installthe rubber grommets andbrass
colletsontotheaileronservo. Testfittheservo
into the aileron servo mount.
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.
2) Remove the aileron servo. Place the
mountontothe wing, aligning the cutoutin the
mount with the cutout in the wing. The two
notches in the mount should face the leading
edge of the wing.
3) While holding the servo mount firmly
in place, trace around it using a pen.
4) Remove the mount, and using a mod-
elingknife,carefullyremovethecovering from
inside the outline you drew.
5) Using 6 Minute Epoxy, glue the servo
mount into place. Remove any excess epoxy
usinga paper toweland rubbingalcohol. Use
piecesofmaskingtapeto hold the trayinplace
until the epoxy fully cures.
✗ ) Peel off the backing from the self
adhesive covering strip. Apply the strip to the
center section of the wing starting from the
bottomtrailingedge.Wrapthestripalltheway
aroundthewinguntil itmeetsthetrailingedge
again. Trim off any excess strip.
✕ ) Mix a generous amount of 30 minute
epoxy. Coat the exposed half of the dihedral
brace, and the remaining wing joiner box and
both root ribs with epoxy. Slide the two wing
halvestogetherand carefully alignthematthe
leading and trailing edges. Wipe away any
excess epoxy using paper towels. Use mask-
ingtape wrapped aroundthecenter section to
hold the halves in place until the epoxy cures.
✖ ) When the epoxy has cured, carefully
remove the masking tape from the wing.
INSTALLING THEAILERON SERVO MOUNT.
Epoxy attach.
Maskingtape.
Pen.
Servo
mount.
 3 ) 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
aroundthewinguntil itmeetsthetrailingedge
again. Trim off any excess strip.

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Install the aileron servo into the servo
mount, withtheoutput shaft towards thelead-
ing edge of the wing, using the wood screws
provided with your radio system. Drill 1/16”
pilot holes through the mount before installing
the screws. This will prevent the wood from
splitting.
1) Thread one nylon adjustable control
horn onto each aileron torque rod. Thread the
horns on until they are flush with the ends of
the torque rods.
2) Thread one nylon clevis at least 5/16”
onto each of the two threaded wires.
3) Withtheaileronservo centered, install
theservoarm onto the servo. The arm should
beinstalledso itisparallelwith thetrailingedge
of the wing.
INSTALLING THE AILERON LINKAGE.
Removecovering.
Epoxy.
4) Slide the pushrod wires through the
servo as shown.
5) With both the aileron servo and the ai-
leronscentered.Tightentheset screws on the
servo.
Pushrodwire.
INSTALLING THE AILERON SERVO.
3) Carefully bend the second nylon tube
up at a 45º angle. This tube is the vent tube.
1) Using a modeling knife, carefully cut
off the rear portion of one of the 3 nylon tubes
leaving 1/2” protruding from the rear of the
stopper. This will be the fuel pick up tube.
2) Usingamodeling knife, cut onelength
ofsiliconfuelline. Connectone end of the line
tothe weighted fuel pick up andthe otherend
to the nylon pick up tube.
INSTALLING THE STOPPERASSEMBLY.
FUEL TANK.

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JUMPER 25. Instruction Manual.
Attach the silicone fuel and pressure pipes
tothetank.Thelowerpipeisthe‘feed’andthe
uppertwothe ‘pressure and fill’. Thefill pipe is
the next pipe.
Vent tube.
FuelPick-upTube.
FuelFill Tube.
Carefully use a lighter or heat gun to
permenently set the angle of the vent tube.
Important: When the stopper assembly is
installed in the tank, the top of the vent tube
should rest just below the top surface of the
tank. It should not touch the top of the tank.
4) 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.
5) With the stopper assembly in place,
the weighted pick-up should rest away from
therear of thetankand move freelyinsidethe
tank. The top of the vent tube should rest just
below the top of the tank. It should not touch
the top of the tank.
6) When satisfied with the alignment of
thestopperassembly tightenthe3mmx20mm
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.
You should mark which tube is the vent
and which is the fuel pick up when you attach
fuel tubing to the tubes in the stopper. Once
thetank is installed insidethe fuselage, itmay
be difficult to determine which is which.
Fueltank.

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Balsa wood.
Blow through one of the lines to ensure
the fuel lines have not become kinked inside
the fuel tank compartment. Air should flow
through easily.
4) Insert the main gear wire into the
mounting slot.
5) Remove the two straps and the gear
wire. Drill four 3/32” pilot holes into the fuse-
lage for the wood screws.
3x10mm.
2) Slide one wheel onto each axle and
pushthem up against the wheelcollars. Slide
the remaining wheel collars with set screws
onto the axles. Push them up against the
wheels and tighten the set screws. The
wheels should spin free and not bind in any
way. If they do bind, loosen the set screws in
the outer wheel collars and move the collars
outasmallamount. Retightenthe set screws.
INSTALLING THE MAINGEAR WHEELS.
1) Slideonewheelcollarwith3mmx6mm
set screw onto each axle. Push the wheel
collarson as far as theywill goand tighten the
set screws.
Be careful not to overtighten the set
screws. Overtightening may cause the
threads to strip.
1) Using a modeling knife, remove the
covering from over the two main gear mount-
ing slots located in the bottom of the fuselage.
INSTALLING THE MAIN GEAR WIRES.
Thestrapsshouldbelocated equal distance
from the inside and outside ends of the wire.
3) The landing gear wire is held in place
using two nylon landing gear straps and four
3mm x 10mm wood screws.
2) Usingthetwo landing gear strapsas a
guide, mark the locations of the four 3mm x
10mmmountingscrewsontothefuselagesur-
face.
Fuel pick-up
tube.
Fuelfill tube.
Vent tube.

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JUMPER 25. Instruction Manual.
Steering arm.
Connector.
Installing steering arm as follow.
Adjust the nose gear steering arm until the
arm is parallel with the fire wall.
NOSE GEAR INSTALLATION.
 1) Install the pushrod housing through the
predrilledholeinthefirewallandintotheservo
compartment. The pushrod housing should
protrude 1/4" out past the front of the firewall.
Make a Z-Bend 1/4" from one end of the plain
wire pushrod.
 2) Place your engine onto the engine
mount. Adjust the engine is centered of the
edges of the engine case.
4) Remove the engine. Using an drill bit,
drill the mounting holes through the engine
mount at the four locations marked.
 3) When you are satisfied with the align-
ment, mark the locations of the engine
mounting.
MOUNTING THE ENGINE.
11cm.
Slide one wheel onto the axle and push
them up against the wheel collars. Slide the
remaining wheel collars with set screws onto
the axles. Push them up against the wheels
andtightentheset screws. The wheelsshould
spin free and
INSTALLING THE NOSE GEAR WHEEL.
Steering arm.
Pushrod wire.

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3/32” Hole.
 5) Bolt the engine to the engine mount
usingthe four machine screws.Double cheek
thatallthescrewsaretightbeforeproceeding.
 6) AttachtheZ-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.
Installthespinnerbackplate,propellerand
spinner cone.
INSTALLING THE SPINNER.
3 x 25mm.
INSTALLING THE SWITCH.
Install the switch into the precut hole in the
side, in the fuselage.
Remove covering.
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.
2.5mm.
3 x 25mm.
Pushrod wire.

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JUMPER 25. Instruction Manual.
Removecovering.
3) Slidethestabilizerintoplace inthepre-
cut slot in the rear of the fuselage. The stabi-
lizer should be pushed firmly against the front
of the slot.
HORIZONTALSTABILIZER.
1) Using a ruler and a pen, locate the
centerlineof thehorizontalstabilizer,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 the backof thetrailing edge of
the stabilizer.
The top of the stabilizer does not have
the hinge pins exposed.
2) Using a modeling knife, carefully re-
move the covering from over the vertical sta-
bilizermounting slot in thetop of thefuselage.
Drawcenterline.
Pen.
6) 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) 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.
5) Remove the stabilizer. Usingthe lines
youjust drew as a guide,carefully removethe
covering from between them using a model-
ingknife.
When cutting through the covering to re-
moveit, cut with only enoughpressure toonly
cut through the covering itself. Cutting into
the balsa structure may weaken it.
Switch.
INSTALLING THE FUSELAGE SERVOS.
Elevator servo.
Rudder servo.
Throttle servo.
Removecovering.

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Pen.
7) 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 the stabilizer mountingarea
and to the stabilizer mounting platform sides
in the fuselage. Slide the stabilizer in place
and realign. Double check all of your mea-
surementsoncemorebeforetheepoxycures.
HoldthestabilizerinplacewithT-pinsormask-
ing tape and remove any excess epoxy using
a paper towel and rubbing alcohol.
VERTICAL STABILIZER
INSTALLATION.
8) 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.
1) Slidethe vertical stabilizer into theslot
inthe top of thefuselage. The bottomedge of
the stabilizer should also be firmly pushed
against the top of the horizontal stabilizer.
4) Slide the vertical stabilizer back in
place. Using a triangle, check to ensure that
thevertical stabilizer is aligned 90ºto thehori-
zontal stabilizer.
When cutting through the covering to re-
move it, cut with only enough pressure
toonly cut throughthe coveringitself. Cutting
into the balsa structure may weaken it.
3) Remove the stabilizer. Using a mod-
eling knife, remove the covering from below
the lines you drew. Also remove the covering
from the bottom edge of the stabilizer and the
bottomandtopedgesofthefillerblock. Leave
the covering in place on the sides of the filler
block.
2) 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.
90º
Vertical
Stabilizer.
Horizontal
Stabilizer.
Remove covering.

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JUMPER 25. Instruction Manual.
Elevator control horn.
CONTROL HORN INSTALLATION.
 1) Locate the two nylon control horns, two
nylon control horn backplates and four
machine screws.
 2) Position the rudder horn on the left side
of fuselage.
ControlHorn.
MountingScrews. Mounting Plate.
 3) Using a 1.5mm drill bit and the control
horns as a guide, drill the mounting holes
through the rudder halves.
4) Install the elevator control horn using
the same method as with the rudder control
horns.
Rudder control horn.
2x20mm.
5) When you are sure that everything is
alignedcorrectly,mix up a generousamountof
30MinuteEpoxy. Applyathinlayertothemount-
ingslotinthetopofthefuselageandtothesides
and bottom of the vertical stabilizer mounting
area. Applyepoxy tothebottomand top edges
of the filler block and to the lower hinge also.
Set the stabilizer in place and realign. Double
checkallof yourmeasurementsoncemore be-
foretheepoxycures.Holdthestabilizerinplace
with T-pins or masking tape and remove any
excess epoxyusing a paper toweland rubbing
alcohol. Allow the epoxy to fully cure before
proceeding.
2) Installthe rubber grommets andbrass
colletsonto the throttle servo. Testfittheservo
into the throttle servo mount.
1) Install adjustable servo connector in
the servo arm.
THROTTLE SERVO ARM
INSTALLATION.
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.
 3) Secure the servos with the screws pro-
vided with your radio system.
 4) Install the pushrod throttle.
AdjustableServo
connector.
Servoarm.

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Thread two nylon clevises onto the
threaded wires at least 10 turns. Attach the
clevises to the elevator and rudder control
horns. You may find it necessary to make
slightbendsinthewiresso they will align with
the control horns without binding.
PUSHROD INSTALLATION.
 1)Plugthe four servo leadsand theswitch
lead into the receiver. Plug the battery pack
lead into the switch also.
2) Wrap the receiver and battery pack in
the protective foam rubber to protect them
from vibration.
INSTALLING THE RECEIVERAND BATTERY.
 3) Route the antenna in theantenna tube
inside the fuselage and secure it to the bot-
tom of fuselage using a plastic tape. See pic-
ture below.
Rudder pushrod.
Elevator pushrod.
Control horn.
Receiver.
Battery.
Antenna.
Antennatube.
Antenna.
Elevator.
Rudder. Steering pushrod.
Throttle.

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JUMPER 25. Instruction Manual.
1) It is critical that your airplane be bal-
anced correctly. Improper balance will cause
yourplanetolosecontrolandcrash. Thecen-
ter of gravity is locate 7.5cm back from the
leading edge of the wing, measured at wing
tip.
2) If the nose of the plane falls, the plane
is nose heavy. To correct this first move the
battery pack further back in the fuselage. If
this is not possible or does not correct it, stick
small amounts of lead weight on the fuselage
1) We highly recommend setting up the
JUMPER 25 using the control throws listed at
right. We have listed control throws for both
Low Rate (initial test flying/sport flying) and
High Rate (aerobatic flying).
2) Turnontheradio system, and withthe
trim tabs on the transmitter in neutral, center
the control surfaces by making adjustments
totheclevisesoradjustableservoconnectors.
The servo arms should be centered also.
BALANCING.
sides under the horizontal stabilizer. If the tail
of the plane falls, the plane is tail heavy. To
correctthis,movethebatteryand receiver for-
ward orif this is not possible, stick weight onto
the firewall or use a brass heavy hub spinner
hub, similar to those offered by Harry Higley.
When balanced correctly, the airplane should
sit level or slightly nose down when you lift it
up with your fingers.
CONTROL THROWS.
 3) When the elevator, rudder and aileron
control surfaces are centered, use a ruler and
check the amount of the control throw in each
surface. The control throws should be
measured at the widest point of each sur-
face!
ATTACHMENT WING - FUSELAGE.
See pictures below:
Dowel.
Rubber band.
Dowels.
Remove covering.
CG=7.5cm

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 4) By moving the position of the adjust-
able control horn out from the control surface,
you will decrease the amount of throw of that
control surface. Moving the adjustable con-
trol horn toward the control surface will in-
crease the amount of throw.
FLIGHT PREPARATION.
 B) Plug in your radio system per the
manufacturer's instructions and turn every-
thingon.
 C) Check the elevator first. Pull back on
theelevator stick. The elevator halves should
move up. If it they do not, flip the servo re-
versing switch on your transmitter to change
the direction.
 D) Check the rudder. Looking from be-
hindthe airplane, movetherudderstick to the
right. Theruddershouldmovetotheright. Ifit
does not, flip the servo reversing switch on
your transmitter to change the direction.
 E)Check the throttle. Moving thethrottle
stick forward should open the carburetor bar-
rel. Ifitdoesnot, fliptheservoreversingswitch
on your transmitter to change the direction.
 F) From behind the airplane, look at the
aileronontherightwinghalf. Movetheaileron
sticktothe right. Therightaileronshouldmove
upandtheotheraileron should move down. If
it does not, flip the servo reversing switch on
your transmitter to change the direction.
 A) Check the operation and direction of
the elevator, rudder, ailerons and throttle.
PREFLIGHT CHECK.
1) Completely charge your transmitter
and receiver batteries before your first day of
flying.
2) Check every bolt and every glue joint
in the JUMPER 25 to ensure that everything
is tight and well bonded.
3) Double check the balance of the air-
plane. Do this with the fuel tank empty.
4) Check thecontrol surfaces. All should
move in the correct direction and not bind in
any way.
5) If your radio transmitter is equipped
withdualrate switches double check thatthey
are on the low rate setting for your first few
flights.
6) Check to ensure the control surfaces
are moving the proper amount for both low
and high rate settings.
8) Properly balancethe propeller. Anout
of balance propeller will cause excessive vi-
bration which could lead to engine and/or air-
frame failure.
We wish you many safe and
enjoyable flights with your
JUMPER 25.
7) Check the receiver antenna. It should
be fully extended and not coiled up inside the
fuselage.
INITIAL FLYING/SPORT FLYING
Ailerons: 3/8” up 3/8” down
Elevator: 3/8 ” up 3/8” down
Rudder: 1/2” right 1/2” left
AEROBATIC FLYING
Ailerons: 1/2”up 1/2”down
Elevator: 5/8”up 5/8” down
Rudder: 1” right 1”left
Do not use the aerobatic settings for
initial test flying or sport flying.