Seagull Models Grumman F8F Bearcat User manual

1
Specications:
Wingspan--------------- 71.0 in (180.3 cm).
Wing area--------------- 1147.0sq.ins (74.0 sq.dm).
Weight------------------- 14.3-15.0 lbs (6.5-6.8 kg).
Length------------------- 62.7 in (159.2 cm).
Engine/Motor size----- 33-45cc gasoline.
Radio--------------------- 8 channels with 10 servos.
ASSEMBLY MANUAL
Code : SEA 324B

GRUMMAN F8F BEARCAT Instruction Manual.
2
ank you for choosing the GRUMMAN F8F BEARCAT ARTF by SG MODELS .
e GRUMMAN F8F BEARCAT was designed with the intermediate/advanced sport
yer in mind. It is a semi scale airplane which is easy to y and quick to assemble. e
airframe is conventionally built using balsa, plywood to make it stronger than the av-
erage ARTF, yet the design allows the aeroplane to be kept light. You will nd that
most of the work has been done for you already. e motor mount has been tted and
the hinges are pre-installed. Flying the GRUMMAN F8F BEARCAT is simply a joy.
is instruction manual is designed to help you build a great ying aeroplane. Please read
this manual throughly before starting assembly of your GRUMMAN F8F BEARCAT Use
the parts listing below to indentify all parts.
Please be aware that this aeroplane is not a toy and if assembled or used incorrectly it is ca-
pable of causing injury to people or property. WHEN YOU FLY THIS AEROPLANE YOU
ASSUME ALL RISK & REPONSIBILITY.
If you are inexperienced with basic R/C ight we strongly recommend you contact your R/C
supplier and join your local R/C model Flying Club. R/C Model Flying Clubs oer a variety
of training procedures designed to help the new pilot on his way to successful R/C ight.
ey will also be able to advise on any insurance and safety regulations that may apply.
INTRODUCTION
WARNING
KIT CONTENTS
3
10
22
6
12
4
5
1
8
9
11
7
13

3
KIT CONTENTS
SEA324 GRUMMAN F8F BEARCAT
1. Fuselage
2. Wing set (2)
3. Tail set (2)
4. Canopy
5. Cowling
6. Wing tube
7. Pilot
8. landing gear
9. Fuel tank
10. Tail wheel
11. Pushrod set
12. Ep Motor box
13. Bomb
ADDITIONAL ITEMS REQUIRED
TOOLS & SUPPLIES NEEDED
in cyanoacrylate glue.
Medium cyanoacrylate glue.
30 minute epoxy.
5 minute epoxy.
Hand or electric drill.
Assorted drill bits.
Modelling knife.
Straight edge ruler.
2mm ball driver.
Phillips head screwdriver.
220 grit sandpaper.
90° square or builder’s triangle.
Wire cutters.
Masking tape & T-pins.
read-lock.
Paper towels.
�33-45cc gasoline engine.
�Computer radio 8 channel with 10
servos.
�Glow plug to suit engine.
�Propeller to suit engine.
�Protective foam rubber for radio
system.
INSTALL THE AILERONS
CONTROL HORN
Fiberglass control horn
1.
Ailerons control horn
Epoxy.
2.
3.
4.
Epoxy.

GRUMMAN F8F BEARCAT Instruction Manual.
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Because the size of servos dier, you
may need to adjust the size of the precut
opening in the mount. e notch in the
sides of the mount allow the servo lead to
pass through.
Place the servo between the mounting
blocks and space it from the hatch. Use
a pencil to mark the mounting hole loca-
tions on the blocks.
Use dental oss or heatshrunk tube to
secure the connection so they cannot be-
come unplugged.
C/A glue
INSTALLING THE AILERON SERVOS
5.
6.
1.
2.
Use drill bit in a pin vise to drill the mout-
ing holes in the blocks.
Apply 2-3 drops of thin C/A to each of
the mounting holes. Allow the C/A to
cure without using accelerator.
1.5mm
3.
4.
Mininum servo spec.
Torqu e : 80 oz-in (5.8 kg-cm) @ 4.8V;
100 oz-in (7.2 kg-cm) @ 6.0V

5
Secure the servo to the aileron hatch us-
ing Phillips screwdriver and the screws
provided with the servo.
Apply 1-2 drops of thin C/A to each of
the mounting tabs. Allow the C/A to cure
without using accelerator.
Remove the string from the wing at the
servo location and use the tape to attach
it to the servo extension lead. Pull the lead
through the wing and remove the string.
C/A glue
7.
8.
9.
10.
Set the aileron hatch in place and use a
Phillips screw driver to install it with four
wood screws.
11.
12.
3x10mm
13.

GRUMMAN F8F BEARCAT Instruction Manual.
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AILERON PUSHROD INSTALLATION
Please see below pictures. Please see below pictures.
INSTALLING THE FLAP PUSHROD
80mm. 80mm.
2.2.
3.3.
4.
14.
1.1.

7
Attach the ap servo to the ap servo
cover. Center the ap servo (or set the
values to 0 for both up and down) and in-
stall the servo arm perpendicular to the
servo centerline. e clevis will attach to
the arm 13/16 inches (21mm) from the
center of the arm.
Use a pin vise and 3/32-inch (2mm) drill
bit to clear the paint from the ap control
horn.
6.
5.
4.
Attach the ap linkage to the control
horn. Slide the clevis retainer over the
forks of the clevis.
7.
Route the servo lead for the ap servo out
at the root of the wing. Connect the ap
servo to the radio system. With the radio
system on, place the ap servo into posi-
tion.
Attach the clevis to the ap servo arm.
8.
Adjust the linkage so the ap is in the
mid-ap position. It may take a few tries
to properly adjust the linkage.
9.

GRUMMAN F8F BEARCAT Instruction Manual.
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12.
13.
14.
Set the ap control at the transmitter to
the down ap position. Adjust the ap
travel at the transmitter until it matches
the control throws listed in this manual.
Fit the ap linkage cover into position.
Check the operation of the ap to make
sure the cover does not interfere with the
ap linkage.
Use canopy glue to attach the cover to the
wing. Use low-tack tape to keep the cover
in position until the adhesive fully cures.
15.
Once adjusted, make sure all clevis re-
tainers are in position. Apply a drop of
threadlock near the clevis, then tighten
the nut against the clevis to keep the link-
age from changing length inside the wing.
10.
11.
Trim the ap linkage cover using a hobby
knife and hobby scissors.

9
INSTALLING LANDING GEAR
Locate items necessary to install Sprin
Landing Gear.
Servo Landing Gear.
2.
16.
Mark.
4.
3.
2.5mm.
5.
Install servo for Retractable landing gear.
6.
M3x12mm
A
1.
Mininum servo spec.
Torqu e : 222 oz-in (16 kg-cm) @ 4.8V;
278 oz-in (20 kg-cm) @ 6.0V

GRUMMAN F8F BEARCAT Instruction Manual.
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8.
9.
Slide the wheel on the axle, then secure it
using the wheel collar.
Collar.
M3x4mm.
12.
10.
11.
Secure the landing gear doors to the
landing gear struts.
Collar.
13.
M3x4mm.
7.
A

11
16.
14.
15.
17.
3x8mm.
3x12mm.
18.
M3x12mm
M3x8mm
19.
20.
21.

GRUMMAN F8F BEARCAT Instruction Manual.
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23.
2) Secure the servos with the screws pro-
vided with your radio system.
.
INSTALLING THE FUSELAGE SERVOS
.
Because the size of servos dier, you
may need to adjust the size of the precut
opening in the mount. e notch in the
sides of the mount allow the servo lead to
pass through.
Install the rubber grommets and brass
collets into all servos. Test t the servos
into the fuselage servo mounts.
Rudder servo.
Elevator servo.
1.
rottle servo.
Elevator servo arm .
THROTTLE SERVO ARM
INSTALLATION
Install adjustable servo connector in the
servo arm as same as picture below:
1.
2.
Rudder servo arm.
INSTALLING THE RECEIVER SWITCH
Install the switch into the precut hole in
the side, in the fuselage.
3/32” Hole.
Trim and cut.
1.
2.
rottle servo arm.
22.

13
.
INSTALLING THE ENGINE SWITCH
Switch.
Trim and cut.
Switch.
3.
1.
2.
INSTALLING THE STOPPER
ASSEMBLY
Using a modeling knife, carefully cut o
the rear portion of one of the 3 nylon
tubes leaving 1/2” protruding from the
rear of the stopper. is will be the fuel
pick up tube.
Using a modeling knife, cut one length of
silicon fuel line. Connect one end of the
line to the weighted fuel pick up and the
other end to the nylon pick up tube.
1.
2.
Carefully bend the second nylon tube up at a
45º angle. is tube is the vent tube.
3.Vent tube.
Fuel ll tube.
Fuel pick up tube.
Test t the stopper assembly into the tank.
It may be necessary to remove some of the
ashing around the tank opening using a
modeling knife. If ashing is present, make
sure none falls into the tank.

GRUMMAN F8F BEARCAT Instruction Manual.
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FUEL TANK INSTALLATION
Slide the fuel tank into the fuselage. Guide
the lines from the tank through the hole in
the ewall.
When satised with the alignment of the
stopper assembly tighten the 3 x 20mm ma-
chine screw until the rubber stopper expands
and seals the tank opening. Do not overtight-
en the assembly as this could cause the tank
to split.
With the stopper assembly in place, the
weighted pick-up should rest away from the
rear of the tank and move freely inside the
tank. e top of the vent tube should rest just
below the top of the tank. It should not touch
the top of the tank.
You should mark which tube is the vent
and which is the fuel pickup when you attach
fuel tubing to the tubes in the stopper. Once
the tank is installed inside the fuselage, it may
be dicult to determine which is which.
1.
2.
Epoxy.
3.
Fuel pick up tube. Fuel ll tube.
Vent tube.
5.
4.
Connect the lines from the tank to the en-
gine and muer. e vent line will con-
nect to the muer and the line from the
clunk tothe carburetor.
Balsa wood.
Blow through one of the lines to ensure
the fuel lines have not become kinked inside
the fuel tank compartment. Air should w
through easily.

15
MOUNTING THE ENGINE
Please see below pictures.
160mm
2.
3.
4.
1.
5x60mm
6.
5.
7.
8.
Ignition Modude.

GRUMMAN F8F BEARCAT Instruction Manual.
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Pushrod wire.
9.
10.
11.
Reinstall the servo horn by sliding the
connector over the pushrod wire. Center
the throttle stick and trim and install the
servo horn perpendicular to the servo
center line.
Move the throttle stick to the closed posi-
tion and move the carburetor to closed.
Use a 2.5mm hex wrench to tighten the
screw that secures the throttle pushrod
wire. Make sure to use threadlock on the
screw so it does not vibrate loose.
COWLING
Please see below pictures.
12.
13.
1.

17
3.
2.
4.
5.
8.
9.
6.
7.

GRUMMAN F8F BEARCAT Instruction Manual.
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10.
11.
12.
13.
Use a drill and drill bit to drill the holes
for the cowl mounting screws. Make sure
the cowl position is correct before drill-
ing each hole.
Install the muer and muer extension
onto the engine and make the cutout in
the cowl for muer clearance. Connect
the fuel and pressure lines to the carbu-
retor, muer and fuel ler valve. Secure
the cowl to fuselage using the M4x25mm
socket head screws.Putting a small length
of silicon fuel tube under the head of the
screw helps with vibration.
Tape the cowl to the fuselage using low-
tack tape.
14.
15.
16.

19
17.
18.
19
20.
21.
1.
Recommend the items necessary to install
the electric power conversion parts
included with your model.
- Motor: 160 - 2700 Watts
- Propeller: 18x8 ~ 20x10
- ESC: 70A - 100A
- 9S- 10S Lipo
ELECTRIC POWER CONVERSION
Locate the items neccessary to install the
electric power conversion included with
your model.
Attach the electric motor box to the re-
wall centered with the cross lines drawn
on the electric motor box and rewall.
Using M5x25mm to secure the motor box
to the rewall. Please see pictures below.
Nylon screw 4x25mm.

GRUMMAN F8F BEARCAT Instruction Manual.
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Attach the motor to the front of the elec-
tric motor box using four 4mm blind nut,
four M4x25mm hex head bolts to secure
the motor. Please see picture shown.
4.
3.
2.
4mm.
5.
M5x25mm and washers.
en, use 5.5mm drill bit to enlarge the
holes on the electric motor box.
6.
7.
5.5mm
Blind nut.
5) Attach the motor to the front of the
electric motor box using four 4mm blind
nut, four M4x20mm hex head bolts to se-
cure the motor. Please see picture shown.
8.
M4x20mm.