Flex innovations FeatherLite RV-8 70cc FLS User manual

RV-8 70cc FLS
ARF and ARFSV
Instruction Manual

BEFORE CONTINUING WITH THIS INSTRUCTION MANUAL OR THE ASSEMBLY OF YOUR
AIRCRAFT, PLEASE VISIT OUR WIKI SUPPORT SITE FOR THE LATEST PRODUCT UPDATES,
FEATURE CHANGES AND MANUAL ADDENDUMS FOR THIS PRODUCT.
wiki.flexinnovations.com/wiki/RV-8_70cc

TABLE OF CONTENTS
Introduction.............................................................................................................................. 1
Specifications: .................................................................................................................................................................1
Required Equipment: ...................................................................................................................................................2
Optional Equipment:....................................................................................................................................................4
Hangar 9®/Ultracote®/Oracover® Colors:...............................................................................................................4
Using this Manual ............................................................................................................................ 5
ARF.............................................................................................................................................. 7
Aileron and Flap Control Horn Installation................................................................................. 7
Control Horn Installation ............................................................................................................................................7
Hinge Installation:..........................................................................................................................................................9
Main Wing Servos and Linkages Installation ...........................................................................10
Ailerons........................................................................................................................................................................... 10
Flaps................................................................................................................................................................................. 12
Elevator Installation ......................................................................................................................13
Control Horn Installation ......................................................................................................................................... 14
Hinge Installation:....................................................................................................................................................... 14
Elevator Servo and Linkage Installation ...................................................................................15
ARF and ARFSV....................................................................................................................... 18
Rudder, Tailwheel Installation ....................................................................................................18
Tail Wheel Installation............................................................................................................................................... 18
Rudder and Rudder Control Horn Installation ................................................................................................. 20
Rudder Hinge Installation........................................................................................................................................ 21
Rudder Control Horn Installation.......................................................................................................................... 22
Rudder Servo and Linkage Installation .....................................................................................24
Push/Pull System, Servo Installed in the Vertical Fin..................................................................................... 24
Installing the Vertical Fin .............................................................................................................27
Pull/Pull System........................................................................................................................................................... 29
Push/Pull System, Servo Installed in Fuselage ................................................................................................. 32
Mounting the Stab ........................................................................................................................34
Landing Gear Installation.............................................................................................................35
Engine and Throttle Servo Installation.............................................................................. 39
DA-70 Engine Installation ............................................................................................................39
DA-70 Throttle Servo and Throttle Linkage Installation............................................................................... 41
DA-60 Engine Installation ............................................................................................................43
Throttle Installation.................................................................................................................................................... 45
Ignition Installation.......................................................................................................................48
Fuel Tank Installation....................................................................................................................50
Exhaust and Cowling Installation...............................................................................................53
Muffler Installation (A) .............................................................................................................................................. 53

Canister Installation (B)............................................................................................................................................. 56
Baffle and Final Cowling Installation ................................................................................................................... 59
Electric Power Setup ............................................................................................................. 63
Motor Installation ..........................................................................................................................63
ESC Installation ..............................................................................................................................65
Battery Tray Installation...............................................................................................................66
Motor/ESC Cooling ........................................................................................................................68
Final Assembly ....................................................................................................................... 69
Radio Installation...........................................................................................................................69
Wing Installation............................................................................................................................72
Pilot Installation (Optional) .........................................................................................................75
Canopy Installation .......................................................................................................................76
Decal Installation ...........................................................................................................................77
Final Setup and Flying Notes............................................................................................... 84
Center of Gravity............................................................................................................................84
Aura 8 Professional........................................................................................................................85
Range Testing.................................................................................................................................86
Before First Flight ..........................................................................................................................86
AMA Safety Code ...........................................................................................................................87
Replacement Parts.........................................................................................................................88
Optional Accessories.....................................................................................................................89
Limited Warranty................................................................................................................... 90

RV-8 70cc FLS Instructions
1
INTRODUCTION
The RV-8 70cc FLS (Feather Light Series) is a 35% scale model of the famous experimental Van’s
Aircraft RV-8. Designer and World Champion Quique Somenzini has taken a completely new
approach with the design of the RV-8 70cc FLS. A massive airframe, with over 2000 square inches
(130.3 sq. dm.) of wing area, that comes in at 23 pounds (10.4 kg) flying weight, offers such an
incredibly lightly loaded airframe, it feels like you are flying something lighter than air. Couple the
extremely light wing loading with key design and geometric details from the master himself, and you
get an aircraft that has a huge flight envelope.
Along with the incredible airframe design of the RV-8 70cc FLS, it is also designed to accept multiple
power systems, including 60cc electric setups that allow you to fly anywhere from 5 to 8 minutes on
a typical 12S Li-Po setup! We also cannot forget about its float-ready airframe either! The optional RV-
8 70cc FLS Float Set includes everything needed to get it on the water and is also available to match
your RV-8 70cc FLS’ color scheme.
This is an airplane that you need to truly experience for yourself, and once you have, you’ll quickly
add one to your hangar! From its insane stability at walking speeds with the flaps down, to classic 3D
and precision aerobatic maneuvers, the RV-8 70cc FLS has the flight performance and versatility that
is for every pilot, of virtually every skill level.
Specifications:
Wingspan:
100 in. (2540 mm)
Length:
90 in. (2288 mm)
Gas Weight:
(DA-70 w/MTW TDH110 Canister)
23 lb. 3 oz. (10.5 Kg)
Electric Weight:
(Potenza 65cc w/12S 6200mAh)
24 lb. 15oz. (11.3 Kg)
Engine/Motor Size:
60-70cc

RV-8 70cc FLS Instructions
2
Required Equipment:
Radio Equipment & Servos:
Transmitter:
8+ channels
Receiver:
8+ channels, high-voltage capable
Receiver Battery:
(2) 2S 4000mAh 15C+ LiPos (FPZBR40002S15 recommended)
Receiver Battery Strap:
(1) Flex Hook and Loop Strap, 300 mm long (FPMA1016)
Aileron, Flaps, Elevators Servos:
(6) Minimum 200 oz/in (14 kg/cm)
Potenza DS22209HV high voltage servos recommended.
Rudder Servo:
Minimum 400 oz/in (28 kg/cm)
Potenza DS494010HV brushless high voltage servo
recommended.
Servo Arms:
Aileron, Flaps, Elevators:
(6) 2-inch Single Arm
Potenza 2-inch Clamping Servo Arm – FPZA1036 recommended.
Rudder:
(Tail-mounted Push-Pull)
2-inch Single Arm
Potenza 2-inch Clamping Servo Arm – FPZA1036 recommended.
Rudder:
(Front-Mounted Pull-Pull)
4-inch Double Arm
Potenza 4-inch Clamping Servo Arm – FPZA1037 recommended.
Servo Extensions:
Ailerons:
(2) 18-inch (460 mm)
Flaps:
(2) 9-inch (230 mm)
Flaps & Ailerons:
(To the receiver or Aura)
(2) 9-inch (230 mm)
Elevators:
(2) 48-inch (1220 mm)
Rudder:
(Tail-mounted Push-Pull):
48-inch (1220 mm)
Servo Extension Safety Clips:
Flex Servo Connector Safety Clips (FPZA1040)
Spinner:
Spinner:
5 inch (140 mm)
Falcon 5-inch Carbon Fiber Spinner – FPMFAL5CGS recommended

RV-8 70cc FLS Instructions
3
Gas Engine Setup
Engine:
60cc to 70cc Gasoline two-stroke engine
Desert Aircraft DA-70 – FPMDA70 recommended
Exhaust:
Follow your engine manufacturer’s recommendation, as well as
local noise restrictions in your area.
DA stock muffler set by Slimline – FPMDA70MUFFLER
recommended for DA-70.
Other Exhaust Options:
MTW TDH110 Rear Discharge Canisters for the DA-70
KS 60 mm drop 2 to 1 header for the DA-70
KS86 Rear Discharge Canister for DA-60
MTW Flexible header 60 mm drop for DA-60
Propeller:
Follow your engine manufacturer’s recommendation.
Falcon Carbon Fiber 25x8W recommended for the DA-70
Engine Standoffs:
(4) 20 mm Aluminum Standoffs for DA-70
or
(4) 30mm Aluminum Standoffs for DA-60
FPM1624 recommended for DA-70
Throttle Servo:
High Quality, Metal Gear Digital Servo
Potenza DS22209HV high voltage servo recommended.
Throttle Servo Extension:
18-inch (460 mm)
Ignition Regulator:
Follow your engine manufacturer’s recommendation.
Ignition Strap:
Flex Hook and Loop Strap, 200mm long (FPMA1012)
Ignition Battery
2S 2000mAh 15C+ Li-Po
FPZBR20002S15 recommended
Ignition Battery Strap:
Flex Hook and Loop Strap, 200 mm long (FPMA1012)
Fuel Tank Strap?
(1) FPMA1014 (2) Battery Hook and Loop Strap Small 260mm Long
(1) FPMA1013 (2) Battery Hook and Loop Strap Small 220mm Long
Fuel Dot:
McFueler Fuel Dot (FPMAMCFUELER)
Electric Setup
Motor:
60-70cc Brushless Motor Equivalent
Potenza High Performance 65cc 185KV Brushless Motor
FPZM65CC recommended.
ESC:
160A HV ESC
Castle Creations Phoenix Edge 160HV, 50V ESC recommended.
Flight Batteries:
2 x 6S 6200mAh Li-Pos
Potenza 6S 6200mAh 40C Li-Pos recommended.
Flight Battery Straps
(2) Flex Hook and Loop Strap, 300mm long (FPMA1016)

RV-8 70cc FLS Instructions
4
Propeller:
Follow your motor manufacturer's recommendation.
Mejzlik 25x12S recommended for the Potenza 65cc Brushless
Motor.
Motor Standoffs:
(4) 2-½inch (63mm) Motor Standoffs
ESC Servo Extension:
18-inch (460 mm)
Optional Equipment:
FPZAURA08PRO
Aura 8 Professional
FPM2019
24oz Lightweight Fuel/Smoke Tank (for smoke)
FPM1623
32oz Fuel Tank (larger tank for longer flight times)
FPMHOLYG2
Holy Smokes G2 Smoke System
FPM2014
Flex Innovations Premium Wing and Tail Bag Set
ISDTD2
ISDT D2 Dual Port AC 200W Charger
FPM2022
Premium Vinyl Graphics Set, RV-8 70cc FLS, Red Scheme (by Callie
Graphics)
FPM2023
Premium Vinyl Graphics Set, RV-8 70cc FLS, Camouflage Scheme
(by Callie Graphics)
FPMAMCFUELER
McFueler Fuel Dot
Hangar 9®/Ultracote®/Oracover® Colors:
Camouflage Scheme:
Ultracote®
Oracover®
Olive Drab (HANU904)
Olive Drab 21-018
Light Gray (HANU882)
Grey 210-011
Orange (HANU877)
Orange 21-060
White (HANU870)
White 21-010
Black (HANU874)
Black 21-071
Red, White and Blue Scheme:
Ultracote®
Oracover®
True Red (HANU866)
Ferrari Red 21-023
Midnight Blue (HANU885)
Dark Blue 21-052
Silver (HANU881)
Silver 21-091
White (HANU870)
White 21-010

RV-8 70cc FLS Instructions
5
USING THIS MANUAL
This manual is for both the ARF and ARFSV versions.
The manual is divided into sections to make the assembly of the airplane easier to follow.
If you have an ARFSV, many of the steps will be completed for you, however, it is important that you
read through this entire instruction manual to familiarize yourself with this aircraft.
Note: the squares “▢” next to each step that can be checked off to help you keep track of the steps
that have been completed.
ATTENTION
Read the ENTIRE instruction manual to become familiar with the features and assembly of the
product before assembly. Failure to assemble or operate the product correctly can result in damage
to the product, personal property and cause serious or fatal injury.
All instructions, warranties and other collateral documents are subject to change at the sole
discretion of Flex Innovations, LLC. For up-to-date product literature, please visit our website at
www.flexinnovations.com and navigate to the product page for this product.
WARNING
This is NOT a toy. This product is not intended for use by children under 14 years of age without
direct adult supervision.
IMPORTANT INFORMATION REGARDING WARRANTY
Please read our Warranty and Liability section before building this product. If you as the purchaser or
user are not prepared to accept the liability associated with the use of this product, you are advised
to return this product immediately in new and unused condition, in the original packaging material,
to the place of purchase.
SAFETY WARNINGS AND PRECAUTIONS
Protect yourself and others by following these basic safety guidelines.
1. This manual contains instructions for safety, operation, and maintenance. It is essential to
read and follow all the instructions in the manual, prior to assembly, setup, or use, in order to
operate correctly and avoid damage or serious injury.
2. In some cases, the written instructions may differ slightly from the photos. In those instances,
the written instructions should be considered correct.
3. This model is not a toy, rather it is a sophisticated hobby product and must be operated with
caution and common sense. This product requires some basic mechanical ability. Failure to
operate this product in a safe and responsible manner could result in injury, or damage to the
product, or other property.
4. This model must be assembled according to these instructions. Do not alter or modify the
model outside of these instructions provided by Flex Innovations, LLC, as doing so may
render it unsafe and/or unflyable. You must take time to build straight, true, and strong. It is
your responsibility to ensure the air worthiness of this product.
5. Use only compatible, appropriate components for the final assembly of this model. Ensure
that the radio system is in functional condition, that the engine is appropriately sized for the
model and that all other components are appropriate for use in this model as specified in this

RV-8 70cc FLS Instructions
6
instruction manual. All components must be installed correctly so that they operate correctly
both on the ground and in the air.
6. Inspect and check operation of the model and all its components before every flight.
7. If you are not an experienced pilot, or have not flown a high-performance model before, it is
recommended that you seek assistance from an experienced pilot in your R/C club for your
first flights. If you're not a member of a club, the Academy of Model Aeronautics (AMA) has
information about clubs in your area whose membership includes experienced pilots.
8. Keep the propeller area clear from such items as loose clothing, jewelry, long hair, or tools, as
they can become entangled. Keep your hands and body parts away from the propeller as
injury can occur.
SPECIAL LANGUAGE DEFINITIONS
The following terms are used throughout the product literature to indicate various levels of potential
harm when operating the product.
NOTICE: Procedures, which if not properly followed, create a possibility of physical
property damage AND a liable or no possibility of injury.
CAUTION: Procedures, which if not properly followed, create a probability of physical
property damage AND a possibility of serious injury.
WARNING: Procedures, which if not properly followed, create the probability of property
damage, collateral damage and serious injury OR create a high probability of
serious injury.
IMPORTANT BEFORE ASSEMBLY
Carefully unpack your aircraft and inspect the parts. Review the manual and gather the required tools
and supplies.
o Remove all parts from their plastic bags, inventory all items and closely examine all the major
airframe components for damage. If any items are missing or you find damaged components,
do not proceed. Please contact customer support.
o Use a covering iron with a covering sock on high heat to tighten the covering as necessary,
paying special attention to the leading edges of the flying surfaces, hinge lines and stabilizer
and wing saddle areas. Apply slight pressure over sheeted areas to thoroughly bond the
covering to the wood. Use caution around seams to prevent inadvertently pulling them loose.
o Pro-Tip: You can use a “Seal-It Pen” to permanently seal any sharp edges or corners of
covering that may come loose in flight.
o Use thin CA to go over any important glue joints, such as the motor box, firewall, servo
mounting rails and any other pre-assembled joints that may see high stress during flight.
o Gather all required components such as motor and radio equipment that will be used to
equip the airplane. Create a new radio program in your transmitter and bind this model
program to the receiver that will be used in the airplane
o IMPORTANT NOTE:
The canopy is attached to the fuselage differently than you may have experienced with other
aircraft. To remove it, remove the two screws. Slide the canopy to the rear (DO NOT LIFT UP).
Once the canopy has been moved aft approximately 1/2-inch (12mm), lift at the rear and
continue moving the canopy to the rear as it is lifted away from the fuselage.

RV-8 70cc FLS Instructions
7
ARF
If your airplane is the ARF version start building from this page through the end of this manual.
AILERON AND FLAP CONTROL HORN INSTALLATION
Required for this section
Components
Tools
Adhesives/Building Materials
o Main Wing Panels (2)
o Aileron Control Horns (4)
o Aileron Control Horn
Base Plates (2)
o Flap Control Horns (4)
o Flap Control Horn Base
Plates (2)
o Aileron and Flap hinges
(16)
o Hobby Knife with a #11
blade
o Isopropyl Alcohol
o 30-minute Epoxy
o Petroleum Jelly
o Paper Towels
o Toothpicks
o Mixing Cups
o Mixing Sticks (something to
mix epoxy with)
The flap and aileron control horns have been marked and bagged individually. It is especially
important that you use the correct control horns corresponding to each control surface.
The Flap control horns do not align with the flap hinge line, rather they are offset towards the rear of
the wing, while the aileron control horns align with the aileron hinge line.
Control Horn Installation
!
1. Prepare the control horns by scuffing the portion of the control horn that is inserted into
the control surface with medium grit sandpaper. Use isopropyl alcohol and a paper towel
to clean the control horn and remove any debris left over after scuffing.

RV-8 70cc FLS Instructions
8
!
2. Locate the aileron and flap control horn slots. You can find them close to the front edge
of the control surface.
210mm
160mm

RV-8 70cc FLS Instructions
9
!
3. Remove the covering using a hobby knife as shown in the picture above.
!
4. Mix an adequate amount of 30-minute epoxy. Apply epoxy to the slot in the control
surface as well as the control horns. Install the control horn and check for proper
alignment. Use isopropyl alcohol and a paper towel to clean up any excess epoxy before
it cures. Let it sit until the epoxy cures.
Quique’s Tip:
To ensure proper alignment of each control horn, you can secure the ball link to the horns and then
glue the horn in place with the ball link attached. This will ensure even alignment of both control
horns.
Hinge Installation:
!
1. Use a hobby knife to open holes in the covering for each hinge in the wings, ailerons and
flaps. Test fit the hinges. Check for minimal hinge gap and overall alignment.
!
2. Use medium grit sandpaper to scuff the portion of each hinge that is inserted into the
wing, aileron or flap. Use isopropyl alcohol and a paper towel to clean the hinge and
remove any debris that may be left after scuffing.
!
3. Use a toothpick or cotton swab to apply a small amount of petroleum jelly to the pivot
point of each hinge. Do not apply petroleum jelly to the entire hinge. The petroleum jelly
is used to prevent glue from adhering to the pivot of the hinge, keeping the hinge
moving free.
!
4. Mix an adequate amount of 30-minute epoxy and apply epoxy to the hinge slots in the
aileron. Insert a hinge into each slot in the aileron. Check for proper alignment. Use
isopropyl alcohol and a paper towel to clean up any excess epoxy before it cures.
!
5. Repeat this process with the flaps.
!
6. Repeat this process for gluing the hinges to the wing. Use masking tape or equivalent to
hold the aileron and flaps in a neutral position. Make sure the hinge gap is as tight as
possible, while still allowing for proper control surface deflection. Wait at least 1 hour
before removing the tape and testing the control surfaces.

RV-8 70cc FLS Instructions
10
MAIN WING SERVOS AND LINKAGES INSTALLATION
Required for this section
Components
Tools
Adhesives/Building Materials
o Main Wing Panels (2)
o Aileron Linkage (2)
o Aileron Servos (2)
o Aileron Servo Arms (2)
o 18-inch (460 mm) Aileron
servo extensions (2)
o Flap Linkage (2)
o Flap Servos (2)
o Flap Servo Arms (2)
o 9-inch (230 mm) Flap
servo extensions (2)
o Ball Links (8)
o M3 x 15 Socket Head Cap
Screw (8)
o M3 Washer (16)
o M3 Lock Nut (8)
o #1 Phillips Screwdriver
o 2.5mm Hex Driver
o 5.5mm Nut Driver
o Thin CA
o Blue Thread Lock
o Servo Connector Safety Clip
Ailerons
!
1. Use a #1 Phillips screwdriver to thread a servo mounting screw into each of the pre-cut
holes in the servo mounting rails in the wing. Remove the screw and apply a small
amount of thin CA to each of the holes to harden the threads cut by the screw. Do not
use CA accelerator. Let the CA fully cure before moving forward.
!
2. Secure an 18-inch (460 mm) servo extension to each of the Aileron servos. Use Flex Servo
Connector Safety Clips (FPZA1040), heat shrink tubing or thread to secure the
connection.
!
3. Insert the aileron servo into the servo bay with the output shaft towards the leading edge
of the wing. Be sure to route the servo lead out of the wing before mounting the servo.
Mount the servo to the wing using the servo mounting screws provided with your servos.
Be sure to install the servos with the long servo extensions in the outside servo openings
of the wing panels (aileron location) and not in the openings close to the root of the wing
panel where the flap servos will be installed.
!
4. Use your radio system to center your aileron servos. Install your aileron servo arm onto
the servo as close to parallel with the hinge line as possible. Apply blue thread lock to the
servo arm screw and fully tighten the screw. If your servo arms have output shaft
clamping screws, apply blue thread lock, and secure them in place at this time.
!
5. Using a pushrod with a length of 2-3/4 inches (70mm), assemble the aileron linkages so
that the total length from center of ball to center of ball is approximately 95mm. Final
length will be adjusted when centering the control surface. Note that the opposite ends
of each aileron linkage have opposite direction threads.

RV-8 70cc FLS Instructions
11
!
6. Attach the linkage to the servo arm. The correct hole location is 2-inches (50.8mm) from
center. If using the recommended 2-inch servo arm, this is the outermost hole.
!
7. With the radio powered-on and the servo centered with the arm parallel to the hinge line,
adjust the linkage length so that the control surface is centered. When satisfied with the
length of the linkage, secure the linkage to the control horn with the hardware in the
following order:
o M3x15 Socket Head Cap Screw
o M3 Washer
o Control Horn (Side 1)
o Ball Link
o Control Horn (Side 2)
o M3 Washer
o M3 Lock Nut
After the steps above are completed and the servo and linkages are installed, the assembly should
appear as shown in the picture above. Both ailerons should appear the same but mirrored
accordingly.
Note: The angle of the linkage is correct. As the servo arm rotates and the control surface deflects,
the linkage will straighten.

RV-8 70cc FLS Instructions
12
Flaps
!
1. Use a #1 Phillips screwdriver to thread a servo mounting screw into each of the pre-cut
holes in the servo mounting rails in the wing. Remove the screw and apply a small
amount of thin CA to each of the holes to harden the threads cut by the screw. Do not
use CA accelerator. Let the CA fully cure before moving forward.
!
2. Secure a 9-inch (230mm) servo extension for to two of the Flap servos. Use Flex Servo
Connector Safety Clips (FPZA1040), heat shrink tubing or thread to secure the
connection.
!
3. Insert the Flap servo into the servo bay with the output shaft towards the leading edge of
the wing. Be sure to route the servo lead out of the wing before mounting the servo.
Mount the servo to the wing using the servo mounting screws provided with your servos.
!
4. Use your radio system to center your flap servos. Install your flap servo arm onto the
servo as close to parallel with the hinge line as possible. Apply blue thread lock to the
servo arm screw and fully tighten the screw. If your servo arms have output shaft
clamping screws, apply blue thread lock, and secure them in place at this time.
!
5. Using a pushrod with a length of 3.5 inches (90mm), assemble the flap linkages so that
the total length from center of ball to center of ball is approximately 112mm. Note that
the opposite ends of each flap linkage have opposite direction threads.
!
6. Attach the linkage to the servo arm. The correct hole location is 2-inches (50.8mm) from
the center of the servo arm. If using the recommended 2-inch servo arm, this is the
outermost hole.
Quique’s Tip:
In order to get the best performance out of the RV-8 70cc FLS, I recommend the use of a Live Wing,
which mixes the flap servos with the ailerons to get a full-span aileron. The flap surface and servo
centering is different than in traditional flap setups, so be sure to follow the next steps closely.
!
7. With the radio powered on and the servo centered with the arm parallel to the hinge line,
adjust the linkage length so that the flap is even with the aileron at its neutral position.
This will allow for the flap to travel in both up and down directions. When satisfied with
the length of the linkage, secure the linkage to the control horn with the hardware in the
following order:
o M3x15 Socket Head Cap Screw
o M3 Washer
o Control Horn (Side 1)
o Ball Link
o Control Horn (Side 2)
o M3 Washer
o M3 Lock Nut

RV-8 70cc FLS Instructions
13
After these steps are completed and the linkages are installed, the assembly should appear as shown
in the above picture. Both flaps should appear the same, though mirrored on their respective sides.
Note: The angle of the linkage is correct. As the servo arm rotates and the control surface deflects,
the linkage will straighten.
ELEVATOR INSTALLATION
Required for this section
Components
Tools
Adhesives/Building Materials
o Elevator Control Horn (4)
o Control Horn Base (2)
o Left and Right Horizontal
Stabs
o Hobby Knife with a #11
Blade
o Isopropyl Alcohol
o 30-Minute Epoxy
o Paper Towels
o Mixing Cups
o Mixing Sticks
o Toothpicks

RV-8 70cc FLS Instructions
14
Control Horn Installation
!
1. Use a hobby knife with a #11 blade to remove the covering from the bottom side of the
elevators. The control horn slots are approximately 1-1/8-inches (35mm) from the
elevator edge as shown in the picture.
!
2. The elevator horns are bagged and marked. Prepare the control horns by scuffing the
portion of the control horn the extends into the control surface with medium grit
sandpaper. Use isopropyl alcohol and a paper towel to clean the control horn and
remove any excess debris left after scuffing.
!
3. Mix an adequate amount of 30-minute epoxy. Apply epoxy to the control horn slots in
the elevator as well as the control horn. Push the control horns into the slot, being sure to
wipe away any excess epoxy with isopropyl alcohol and a paper towel.
Quique’s Tip:
To better help align the control horns with one another, use the provided hardware to secure the
control horns to the ball link. This will keep them aligned while they are glued in place.
Hinge Installation:
!
1. Use a hobby knife to open holes in the covering for each hinge in the horizontal stabs
and elevators. Test fit the hinges. Check for minimal hinge gap and overall alignment.
!
2. Use medium grit sandpaper to scuff the portion of each hinge that is inserted into the
horizontal stabs or elevators. Use isopropyl alcohol and a paper towel to clean the hinge
and remove any debris that may be left after scuffing.
35mm

RV-8 70cc FLS Instructions
15
!
3. Use a toothpick or cotton swab to apply a small amount of petroleum jelly to the pivot
point of each hinge. Do not apply petroleum jelly to the entire hinge. The petroleum jelly
is used to prevent glue from adhering to the pivot of the hinge, keeping the hinge
moving free.
!
4. Mix an adequate amount of 30-minute epoxy and apply epoxy to the hinge slots in the
elevator. Insert a hinge into each slot in the elevator. Check for proper alignment. Use
isopropyl alcohol and a paper towel to clean up any excess epoxy before it cures.
!
5. Repeat this process for gluing the hinges to the horizontal stabs. Use masking tape or
equivalent to hold the elevators in a neutral position. Make sure the hinge gap is as tight
as possible, while still allowing for proper control surface deflection. Wait at least 1 hour
before removing the tape and testing the control surfaces.
ELEVATOR SERVO AND LINKAGE INSTALLATION
Required for this section
Components
Tools
Adhesives/Building Materials
o Horizontal Stabilizer
Assemblies (2)
o Horizontal Stabilizer
Carbon Fiber Tube
o Fuselage
o Elevator Servo (2)
o Elevator Servo Arm (2)
o 48-inch (1250mm) Servo
Extension (2)
o Left and Right Horizontal
Stabs
o M3x15 Socket Head Cap
Screw (8)
o M3 Washer (8)
o M3x12 Washer (4)
o M3 Lock Nut (4)
o 2.5mm Hex Driver
o 5.5mm Nut Driver
o #1 Phillips Screwdriver
o Servo Connector Safety Clip
!
1. Use a #1 Phillips screwdriver to thread a servo mounting screw into each of the holes in
the servo mounting rails in the horizontal stabilizer. Remove the screw and apply a small
amount of thin CA to each of the holes to harden the threads cut by the screw. Let the CA
fully cure before moving forward.

RV-8 70cc FLS Instructions
16
!
2. Insert the elevator servo into the mounting location with the output shaft towards the
horizontal stab tube. Mount the servo to the stab using the mounting screws provided
with your servos. Note that the servo wire will exit on the stab tube side of the servo.
!
3. Power on your radio system to center the servo. Install a 2-inch (51mm) servo arm onto
the servo. Apply a small amount of blue thread lock to the servo arm screw and secure it
in place. If your servo arm has clamping screws, apply blue thread lock to these screws
and secure them in place. Note that you may need to power off the model and rotate the
servo arm by hand to have access to each clamping screw.
!
4. Using a pushrod of 2 1/8-inch (55mm) length, assemble the elevator linkages and ball
links so that the total length from center of ball to center of ball is approximately 3-1/8-
inches (78mm). Final length will be adjusted when centering the control surface. Note
that both ends of the elevator linkages have opposite direction threads.
!
5. Attach the linkage to the servo arm. The correct hole location is 1 3/4-inches (44mm)
from the center of the servo arm. If you are using the recommended servo arm, this is the
second hole from the outside. The order of hardware components, starting from the top
of the servo is as follows:
o M3x15 socket head cap screw
o M3 washer
o Ball Linkage
o Servo Arm
o M3 washer
o M3 locknut
!
6. Attach the linkage to the control horn. The order of hardware components, starting from
the tip of the stabilizer is as follows:
o M3x15 socket head cap screw
o M3 washer
o Control Horn #1
o Ball Linkage
o Control Horn #2
o M3 washer
o M3 locknut