3DHobbyShop.com EBT Assembly Manual

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3DHobbyShop.com EBT Assembly Manual
Thank you for purchasing this 3DHobbyShop ARF RC aircraft. If you have any issues, questions,
concerns or problems during assembly, please contact our tech department at:
Info@3DHobbyShop.com or 1-830-990-6978 10am-5pm Central M-F
SAFETY in Assembly
During assembly of this aircraft, you will be asked to use sharp knives and hobby adhesives. Please
follow all safety procedures recommended by the manufacturers of the products you use, and always
follow these important guidelines:
ALWAYS protect your eyes when working with adhesives, knives, or tools, especially power tools. Safety
glasses are the best way to protect your eyes.
ALWAYS protect your body, especially your hands and fingers when using adhesives, knives, or tools,
especially power tools. Do not cut toward exposed skin with hobby knives. Do not place hobby knives on
tables or benches where they can roll off or be knocked off.
ALWAYS have a first-aid kit handy when working with adhesives, knives, or tools, especially power tools.
ALWAYS keep hobby equipment and supplies out of the reach of children.
SAFETY in Flying
ALWAYS fly your aircraft in a safe area, away from spectators.
ALWAYS fly your aircraft in a safe manner, within your control.
NEVER fly too close to yourself.
ALWAYS wear eye protection while operating your model aircraft.
ALWAYS keep your hands and body clear of propellers.
ALWAYS observe lipoly battery safety procedures.
REQUIRED ITEMS
Thin CA Glue (Super Glue, hobby grade)
12-30 Minute Epoxy Glue (NOT 5-minute Epoxy)
Hobby Knife
Small Phillips Screwdriver
Set Metric Allen Wrenches or Hex-Drivers
Small Pliers
Wire Cutters
Rubbing alcohol
Paper towels
Masking tape
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Assembly Instructions
UNPACK
Unpack your airplane and examine the components. Check for damage of any kind.
WRINKLES
Your EBT was packed in plastic at the factory without any wrinkles in the covering. You may notice some
wrinkles now; more likely, you will notice a few in a day or two or the first time you take the plane out to
the flying field. These wrinkles are the result of wood shrinkage and/or expansion. Balsa wood changes
size and shape slightly as it is exposed to varying humidity in the air. This is a natural property of balsa
wood. As your airplane adjusts to the weather in your part of the world, wrinkles may appear and
disappear.
Wrinkles may be removed with the gentle application of heat to the covering material on your airplane.
The best tool to use is a heat gun. Apply the heat gently: the covering material will shrink as you apply
the heat, and this will remove the wrinkles. BE CAREFUL! Too much heat applied too quickly can
damage the covering, either by causing it to pull away from the wood at seams and corners or even by
melting it. The covering will shrink at low temperature with patient application of heat. Wrinkles do not
affect flight performance, so it is not necessary to remove them.
WORK AREA
Model airplanes are built with many small, lightweight parts. For this reason, you will need an organized,
well-lit work area. If you work over carpet, and you drop a small fastener, it will likely disappear forever.
Hobby glues can damage furniture, so it is wise to cover the table you are working on to protect its finish.
Your EBT includes hardware packaged in clear plastic bags. We recommend keeping a bowl with a tight
lid on your work table, and keeping all of the hardware in the tightly closed bowl during construction. This
helps prevent loss of important parts.
TERMS
Use this illustration to familiarize yourself with the names of parts of an airplane.
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SKILL LEVEL
The EBT is a basic trainer aircraft with aerobatic capability. It is appropriate as a first airplane for a
student pilot who is working with an experienced instructor. We recommend using caution if you are
attempting to teach yourself how to fly. Teaching yourself to fly is VERY DIFFICULT to do. The use of a
quality flight simulator program will help greatly. We recommend spending many hours on a flight
simulator before attempting your first solo flight, and the very best way to learn is with an instructor.
Finding an Instructor
The best way to find an instructor pilot is to join the AMA (Academy of Model Aeronautics), the national
organization of RC flying clubs. AMA membership includes insurance coverage and a subscription to the
AMA modeling magazine. Please contact the AMA for details at http://www.modelaircraft.org/ or 1-800-IFLY-AMA (1-800-435-9262). The AMA can put you in contact with clubs in your area. We highly
recommend joining the AMA.
Going it alone?
If you are unable to find an instructor pilot and are forced to learn to fly by yourself, here are some tips:
1. Purchase a flight simulator program for use on your home computer. This is the single best
preparation for flying. Here are some recommended simulators:
FSOne
RealFlight
ReflexXTR
AeroFly Pro
http://www.fsone.com/
http://www.realflight.com/
http://www.modelrectifier.com/rc-products/flight-simulators.asp
http://www.aerofly.com/
2. Purchase and read a good book on the subject, such as The Pilot’s Guide to Mastering RC Flight by
Scott Stoops. Available from 3DHobbyShop or www.RCPilotGuide.com
3. Contact a club and try to arrange to have an experienced pilot fly the maiden flight of your aircraft for
you. An experienced pilot can trim the aircraft for best flight and spot any potential problems, which will
make your first flight much easier.
Remember – Teaching yourself to fly without help is EXTREMELY DIFFICULT. Working with an
instructor pilot is the best way.
RADIO
Your EBT airplane will require a radio with a minimum of 4 channels of control. These 4 channels are
used to control 4 aircraft functions: Throttle, Rudder, Elevator, Ailerons.
THROTTLE – Controls motor speed and power. Add throttle to accelerate and climb, reduce throttle to
decelerate and descend.
RUDDER – Controls YAW. Turns the aircraft right or left in the air and on the ground.
ELEVATOR – Controls PITCH. Points the nose of the airplane UP or DOWN.
AILERON – Controls ROLL. Used to hold the airplane’s wings level to the ground and to bank in turns.
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Use the following illustration to familiarize yourself with ROLL, PITCH, and YAW.
SERVOS
Your EBT will require 4 servos. We recommend ONLY the Hitec HS-65 servo. The cutouts in the
airplane are sized exactly for this servo.
MOTOR
Your EBT requires a brushless outrunner-type electric motor. We recommend the TORQUE 2818T-900
or TORQUE 2814T-820 brushless motors for the EBT. They will fit the holes in the firewall perfectly.
Other motors that can be used include:
Hacker A30-16M
AXI 2814
E-Flite Power 10
…and many other brushless outrunner motors that weigh 100-150 grams.
Some of these motors will fit the firewall holes perfectly, others will need new screw holes in the firewall.
To be certain of a perfect fit and good quality, we highly recommend the TORQUE motors.
SPEED CONTROL
Your EBT requires a brushless electronic speed control (ESC). For the size of motors typically used in
the EBT, ESC’s from 35-45 amps are recommended. Some ESC’s are equipped with an ON-OFF
switch. Usually, this switch shuts down the entire aircraft radio and power system. If your ESC has a
switch, we highly recommend making the small rectangular hole needed to mount it to the fuselage side
of your EBT. DO NOT simply allow the switch to flop around inside the aircraft, it could accidentally
switch off in flight, and that will definitely cause a crash.
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POWER SYSTEM ASSEMBLY AND MOUNTING
Locate the fuselage of your EBT. In the front of the fuselage is the FIREWALL, the flat plate the motor
mounts to. In the firewall are 4 small holes arranged in a square, and large rectangular hole at the
bottom. Look at the firewall from the back, inside the airplane. You will see that behind each of the four
small holes are blind nuts installed from the rear. These nuts accept the 4 screws which you will use to
mount the motor to the airplane.
Your motor probably came without any mount attached to it. You will need to assemble your motor with
its X-shaped mount for mounting to the firewall. The following sequence demonstrates how to assemble
a TORQUE brushless outrunner motor for installation into the EBT; other brushless motors are very
similar.
This is how the motor arrives in the box:
First, install the shaft collar, tightening the set screw.
Next, install the X-mount with the four short screws.
Then, turn the motor around.
Next, install the prop adaptor with the 4 long screws.
The prop washer and nut go on as shown.
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After the motor is assembled, use 4 black 3mm screws to attach it to the firewall as shown below:
Your ESC (electronic speed control) probably will not come with all necessary connectors installed, most
brands do not. You will need to attach the proper connectors for the battery and possibly the motor.
Refer to the following diagram for assistance (NOTE: see back cover for a color version of this diagram):
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NOTE: The male and female power connectors are attached to the battery and ESC with solder. If you
are unable to solder, we recommend finding an experienced person to solder these connections for you,
as these are critical connections. After soldering, these connections must be insulated, preferably with
heat-shrink tubing.
NOTE: The female power connector is soldered to the battery. The male power connectors (the one with
metal contacts sticking out) is soldered to the ESC. This helps to prevent shorting of the battery when it
is not in use.
NOTE: Be sure that the RED (+) wire of your battery connects through the power connectors to the RED
(+) wire of your ESC. Black should likewise connect to black.
NOTE: The ESC to radio connection plugs into the “Throttle” channel of your receiver. On most systems,
this not only provides control for the ESC, but also provides power to the radio system. This plug must be
connected to the receiver correctly. On some receivers, it can be plugged-in upside down. If so, the
system will not operate, and will appear dead. Please consult your radio instructions if you need
assistance in hooking up your radio connections.
After the proper connectors needed to attach to the battery and motor are installed on your ESC, connect
your ESC to your motor. Feed the ESC into the fuselage through the rectangular hole below your motor
in the firewall. Draw the ESC and its wires into the fuselage, and route them up, through the battery tray,
into the top of the fuselage, as shown below:
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Use velcro to attach the ESC to the inside of the fuselage as shown below: Be sure to use velcro. Do not
glue the ESC inside the fuselage. This will become important later.
The landing gear is assembled next. Please study the following diagram to see how the landing gear is
assembled.
NOTE: The Fiberglass Wheel Pants are optional. They do make the EBT look nicer, with their
aerodynamic appearance, but because a student pilot’s first several landings tend to be rough, we
recommend doing your first several flights without the wheel pants. The following assembly sequence
shows landing gear assembly without wheel pants. Pant installation will be explained afterwards.
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Begin the landing gear assembly by locating the axles and axle nuts, which are packed in the same bag
as the velcro strips. Use the axle nuts to attach the axles to the aluminum landing gear legs as shown.
NOTE: DO NOT OVER-TIGHTEN THE NUT! BE CAREFUL!
Slide the wheel onto the axle as shown. Slide retaining collar onto axle and tighten with 1.5mm allen
wrench or hex driver.
Use your hobby knife to open up the two holes for the landing gear in the bottom of the airplane as
shown, and attach the landing gear to the airplane with 2 3mm black screws. NOTE: The required nuts
are already installed inside the airplane.
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Later, to install the wheel pants, remove the axle nut and remove the axle with wheel and retainer. Slide
the axle with wheel and retainer inside the wheel pant as shown, and then attach the pant-axle-wheel
assembly back onto the landing gear with the nut.
NOTE: The landing gear supplied with the EBT is lightweight, and is suitable for pavement, smooth
ground, and mown grass. If you fly from very rough surfaces, your wheels will wear out quickly.
Replacements are available from 3DHobbyShop. Larger, bouncier wheels, which do weight slightly more,
are also available from 3DHobbyShop.
NOTE: Your EBT’s aluminum landing gear legs are very strong and lightweight. They will spring back
from most bad landings. However, a very hard hit may bend your landing gear legs. If this happens,
remove the gear legs from the airplane, bend them back into shape, and then re-install them onto the
airplane.
NOTE: Your EBT can use a wide variety of propellers. The landing gear legs, as supplied, are tall
enough for props up to 12 inches in diameter. If you wish to use a larger prop, remove the legs from the
airplane and bend to them to make them taller and less wide – this is easy to do – then re-install them
onto the airplane. These legs may be bent to fit up to 14 inch propellers.
Turn the fuselage over so that it is sitting on the landing gear. Locate the holes shown in the following
pictures. You will need to use your hobby knife to remove the covering as shown. These holes are
mounts for the wing-retaining dowels.
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Locate the two round, hardwood dowel pieces in your kit. Slide them into the fuselage through the holes
until an equal amount is sticking out both sides of the fuselage. Mix up a small amount of 12-30 minute
epoxy glue and apply the glue to the dowel-to-fuselage joint from the inside of the fuselage. A Q-tip type
cotton swab works well for this, or a small disposable brush.
Using your hobby knife, remove the covering over the slot in the tail-end of the fuselage (on both sides)
as shown:
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Using your hobby knife, also remove the covering over the pushrod-tube outlet in the top of the fuselage
as shown:
Remove the elevator from the horizontal stabilizer and slide the elevator into the slot as shown. Then,
slide the horizontal stabilizer in, as shown. Make sure both are right-side-up.
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Slide the elevator back into the horizontal stabilizer as shown:
Align the horizontal stabilizer with the fuselage as shown:
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When the stabilizer is fully aligned, use your hobby knife as show to VERY lightly cut through the covering
on the bottom of the stabilizer where the stabilizer meets the fuselage, on both sides.
NOTE: DO NOT CUT INTO THE WOOD! CUT ONLY THE COVERING.
Slide the stabilizer out of the fuselage enough to peel away the covering you just cut, as shown (you will
need to complete the cut at the front and back to remove this piece.)
Mix some 12-30 minute epoxy, apply it to the bare-wood area, and slide the horizontal stabilizer back into
position in the fuselage.
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Allow the epoxy to cure.
After the epoxy has cured, we will glue the hinges in place. All of the hinges on your EBT are glued the
same way. First, flex the elevator up and down to insure that it moves freely 45 degrees up and 45
degrees down, Consult the following diagram:
Apply two large drops of thin, hobby-grade CA glue (super glue) to each hinge as shown. We use only
THIN CA glue so that the glue will wick along the hinge material, into the slots and saturate the wood
around the hinge. If any glue runs out of the slot onto the surface of your airplane, wipe it up quickly with
paper towel. If you do get any drips of CA on your airplane, “CA Glue Remover” is available from most
hobby dealers if you wish to remove the glue residue from the covering.
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Use your hobby knife to remove the covering over the pushrod tube outlet on the bottom of the right side
of the fuselage, just in front of the horizontal stabilizer, as shown:
Take the vertical stabilizer, remove the rudder from the stabilizer, and glue the vertical stabilizer into the
slot on top of the fuselage with 12-30 minute epoxy, as shown:
Take the rudder, and cut the tip off of the lowest hinge, as shown.
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Slide the rudder into the vertical stabilizer and rear of the fuselage as shown, and check to make sure the
rudder swings freely 45 degrees in each direction. Glue the hinges with thin CA glue.
Locate the tailwheel pieces as shown: Wire, Wheel, Retainer, and Bracket.
Slide the wheel onto the wire as shown, and fasten with the retainer. Tighten the retainer set-screw with
a 1.5mm metric allen wrench or hex driver.
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Slide the metal bracket onto the wire, and then push the wire into the bottom of the rudder as shown.
Use two screws to attach the bracket to the bottom of the fuselage as shown. Place a drop of thin CA
glue onto the spot where the wire is pushed into the rudder.
Place tape over the wire and around rudder as shown.
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Locate the two long, wire pushrods. Locate the screw-threaded end of the pushrods. Screw the nylon
links onto the pushrods are show. Screw at least 6-7 complete revolutions with the link onto the rod.
The longer of the two rods is for rudder control. Slide the un-threaded end of the rod into the rudder
pushrod tube through the pushrod tube opening on the top of the fuselage (the one you opened with your
hobby knife by removing the covering over it). The rod should slide smoothly in the tube with little
resistance. If there is resistance, lubricate the rod with cooking oil or household oil. The rod will protrude
into the servo compartment as shown:
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Bend the rod slightly a few inches from the end as shown, and remove a small rectangle of covering from
the rudder in the place shown:
Take one of the nylon control horns. The horns are made with small holes for the links to attach to.
These holes are too small for the links to easily go into, they will usually need to be opened up with your
hobby knife or a small drill bit.
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On the bottom of the control horn are two sharp spikes. These spikes penetrate into the wood and are
held in place by glue. The spikes will often stick out of the other side of the rudder and elevator after they
are pressed in. This is normal, please do not cut any of the spikes off. Please consult the following
diagram for control horn installation:
Apply 12-30 minute epoxy glue to the spikes and the bottom of the control horn. Push the horn firmly into
the rudder as shown until the base of the horn is seated flush against the surface of the rudder as shown
in the diagram. Some epoxy will squeeze out around the base of the horn. This is normal. Clean up
excess epoxy with rubbing alcohol on a paper towel. Allow the epoxy to cure.
Attach the link to the outermost hole on the control horn as shown.
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Slide the elevator pushrod into the elevator pushrod tube and into the servo compartment. Install the
elevator control horn in the same manner as the rudder control horn in the location shown. When you
remove the small rectangle of covering as sown, you will see that the elevator is made of two kinds of
wood, soft balsa wood and a strip of hardwood. You cannot push the control horn spikes into the
hardwood, instead push them into the soft balsa wood as shown. Use plenty of 12-30 minute epoxy.
Attach the link to the outermost hole on the control horn.
Again, open the hole in the control horn for the link as necessary.
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Both pushrods will be protruding into the servo compartment as shown:
Remove your servos from their packages, and find the longest servo arm supplied with your HS-65 servo.
This long servo arm is overkill. If your radio does not have adjustable endpoints, dual rates, or another
function to limit throw, do not use the long arms. In that case, use the arms which came installed on the
servos in the package. Only use the long arms if your radio has features to limit control throw.
We use the long arms if possible as they allow more aerobatic performance later on after your training.
The EBT comes with 4 adjustable pushrod connectors. The connector screws on to the outermost hole
on your servo arms.
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Here are all of the parts for the pushrod connector:
For the arms included with the HS-65 servos, discard the washers. They are used only on thinner servo
arms.
The outermost hole in the servo arm must be opened up to a larger diameter with your hobby knife as
shown. For a cleaner, more accurate job, use a drill and drill bit.
Assemble the pushrod connector onto the servo arm, tighten down the nut only to a snug fit. The
pushrod connector should rotate freely within the servo arm. Apply a small drop of thin CA glue to the
center of the nut to lock the nut onto the thread. DO NOT skip this step, or the nut may fall off in flight,
causing a crash!
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Install your rudder and elevator servos into the servo compartment as shown:
Slide the completed servo arms, with connectors, onto the pushrods and onto the servos as shown:
The rods will bend slightly as shown. DO NOT tighten the pushrod connectors onto the pushrods yet.
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Mount your receiver to the side of the fuselage as shown with velcro. Connect the ESC to the
“THROTTLE” channel port on the receiver. Connect the rudder and elevator servos to the “RUDDER”
and “ELEVATOR” port on the receiver. Consult your radio system manual for assistance if needed.
The wing of the EBT is constructed in halves. We will complete the assembly of each half before joining
them. Take one wing half and make sure the aileron flexes easily up and down. It is not necessary for
the aileron to flex 45 degrees. Instead, the aileron will only flex half as much as the other surfaces.
Verify that the aileron is in position, then apply 2 large drops of thin CA glue to each aileron hinge. Clean
up any excess CA glue with a paper towel.
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Use your hobby knife to open up these holes in the covering on the bottom of the wing as shown:
Take a servo, feed the servo wire through the wing as shown:
Mount the servo as shown with the servo mounting screws. Using a ruler to measure the location, mount
a control horn into the aileron as shown, 2 and 5/16ths inch from the inner end of the aileron to the outer
edge of the horn. Mount this control horn in the same way you mounted the elevator and rudder horns,
but the spikes will not stick out the other side, since the aileron is thicker. Use 12-30 minute Epoxy, as
before.
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Assemble the servo arm with pushrod connector as before, and use one of the short wire pushrods. You
will need to open up the outermost hole on the control horn as before. Install the bent wire end of the
pushrod into the control horn on the aileron, and feed the other end into the pushrod connector, as
shown. DO NOT tighten down the pushrod connector yet.
Repeat all these steps for the other wing half.
Take both wing halves and the plywood dihedral brace (shown below). Notice the dihedral brace is bent
slightly “up” at each end.
Apply 12-30 minute epoxy liberally to one-half of the brace. Insert the brace into one half of the wing, as
shown, note that the brace is pointing “up” as shown in the photo above:
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Apply epoxy to the other side of the brace, and to the bare wood on the inner end of the wing half. Be
sure to use plenty of Epoxy. Slide the wing halves together.
Some epoxy will squeeze out of the joint. This is normal (if you used enough epoxy!) . Clean up any
excess epoxy with alcohol on a paper towel. Use a piece of masking tape to hold the wing halves
together and allow the epoxy to cure.
Make sure there is NO propeller on your motor. Turn on your transmitter. Attach a charged battery to the
battery plug on your ESC and turn your airplane on. Probably, your servos will spin and their servo arms
will no longer be in the correct position. This is why we did not tighten the pushrod connectors earlier.
Remove the servo arms and put them back on in the correct positions as shown. Now, tighten the
pushrod connectors with a 1.5mm allen wrench or hex driver as shown.
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Move your elevator and rudder control sticks. Check to see that the controls move as indicated in the
diagram below:
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If your controls do not move as shown, use the servo-reversing feature on your transmitter to correct this.
Consult your radio system manual for assistance.
Again, make sure there is NO PROPELLER mounted to your motor. Advance your throttle stick and
check to see which direction your motor spins. Consult the diagram below:
Once the controls for the rudder, elevator, and throttle operate as shown, disconnect your battery. Now
you are ready to connect the wing to the fuselage.
Although there are different methods of controlling two aileron servos with one channel of your radio, the
simplest is the servo Y-connector. If you use a Y-connector, plug each of the aileron servos into one of
the female ports on the Y connector, and plug the male end of the y-connector into the “AILERON”
channel port of your receiver, as shown:
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Place the wing on top of the fuselage as shown. Your kit includes 4 large rubber bands, take two of the
bands and connect them between the wooden dowels as shown:
Take the second two bands, and install them in a “crossover” pattern on top of the first two bands, as
shown:
Make sure the wing is properly seated on top of the fuselage, and is centered, with the wing center seam
lined up with the center of the fuselage.
NOTE: If you store your rubber bands inside a plastic “zip-lock” style bag, they will last for a long time.
Suitable replacement bands may be purchased at most office-supply stores. If using smaller, lighter
bands, use more of them. 6 or even 8 bands may be required if they are significantly smaller than the
original bands.
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Connect your battery to your airplane once again. Move the aileron control stick. Consult the diagram
below for the correct aileron direction of movement:
If your ailerons do not move as shown in the diagram, use your servo reversing feature on your
transmitter to correct this.
Disconnect your battery. Make sure your battery is disconnected. We are going to attach the propeller to
the motor. NOTE: The majority of injuries experienced by pilots of electric aircraft happen when the prop
is first attached to the motor and, due to misuse of transmitter functions, the motor start to run
unexpectedly. Be careful! Do not connect your battery to your airplane in your house or workshop if a
propeller is attached to your motor.
The propeller fits onto the threaded shaft on the front of your motor. Some propellers come with different
spacers to fit different sized motor shafts. Find and use the correct mounting spacer if your propeller
came packaged with them. The propeller can be installed correctly, or backwards. If you install the
propeller facing backwards, the airplane will have less than half the intended power, because the
propeller runs very inefficiently if installed backwards. This is probably the most common mistake made
by first-time pilots in assembling their aircraft.
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99% of propellers have an easy method to determine front from back. They have the size of the propeller
molded, written, or stamped into the propeller blade near the center hub. Locate these numbers on your
propeller. They are on the front, and they should point toward the front of the airplane when the prop is
installed.
After the prop is slid onto the prop shaft, install the washer and the nut onto the shaft and tighten. NOTE:
most high-quality brushless outrunner motors use aluminum prop shafts and nuts. These are very
lightweight and very fragile. Do not use a long wrench or socket-driver to tighten them. You will likely
strip the nut. Use a nut-driver or a small pair of pliers and BE CAREFUL.
Picture of properly installed propeller:
The next step is balancing. Balancing is critical for good flight performance. DO NOT SKIP THIS STEP!
On an electric airplane, the battery is a heavy component, and it is also usually easy to move around.
Therefore, to adjust the balance-point of the aircraft (also called the Center of Gravity), we move the
battery forward and back within the airplane.
The EBT is designed to have a wide range of allowable balance points. In general, if the balance point is
forward (more weight in the nose of the airplane), the airplane is more stable and easier for a beginner to
fly. In general, if the balance point is rearward (more weight in the tail of the airplane), the aircraft is more
maneuverable, but also more difficult to fly.
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We measure the balance point by supporting the aircraft on the tips of our fingers under the wing, as
shown.
ALWAYS MAKE SURE YOUR BATTERY IS DISCONNECTED BEFORE CHECKING BALANCE!
The balance point is that point at which, when we hold the airplane by just our fingertips at that exact
point, the airplane hangs perfectly level, without the nose or the tail hanging down.
We measure the balance point from the front (or “leading edge”) of the wing, as shown in the diagram:
For your first flights, balance the aircraft at 2.75 inches from the leading edge of the wing. Later, as you
progress, the EBT can be balanced farther back, to 3.75 inches, to perform aerobatic maneuvers.
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We adjust the balance point by first moving the battery forward and back along the battery tray in the
bottom of the fuselage. If you are using a lightweight motor, your battery will be forward, as shown in the
first photo. If you are using heavier motor, your battery will be farther back, as shown in the second
photo.
In some cases, it will be necessary to add small amount of weight in the nose to achieve the 2.75 inch
balance point. We have used a variety of small weights: coins, fishing sinkers, washers, modeling clay –
attached to the floor of the fuselage just inside the vent hole at the bottom of the firewall. If you use nose
weight, make sure it is firmly attached and cannot come loose in flight. Modeling clay is particularly good,
as it can be easily removed when desired.
Once you have determined the proper position for your battery pack, attach the pack to the battery tray
with the remaining self-adhesive velcro, and use the included velcro-strap “seat belt” to anchor the battery
to the tray. The “seat belt” is necessary to prevent your battery from ejecting in flight, and causing a
crash.
The battery compartment is covered with the included magnetic battery hatch while in-flight, as shown:
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Remove the propeller, turn on your transmitter, connect the battery to the airplane, and set the control
throws as shown (NOTE: Make sure the control surfaces are centered, in the middle of their throw, when
the transmitter stick is centered):
Move each of the control sticks to the farthest point right, left, up, down. Measure the throw (the total
movement) of each control surface. Use your transmitter controls for endpoint to set the throws to the
values shown below.
RUDDER: ½ inch right, ½ inch left
ELEVATOR: 3/8ths inch up, 3/8ths inch down
AILERONS: ¼ inch up, ¼ inch down
These throws are proper for training and gentle flying.
NOTE: If your transmitter is not equipped with any features to change control surface throw, then you will
change throw by changing the length of the servo arms attached to your servos. A shorter servo arm (or
using a hole in the servo arms which is closer to the servo arm center screw) will result in less control
surface throw.
Properly charge your Lipoly battery ONLY on an approved Lipoly charger. Fully charge your transmitter.
Check all control horns to be sure they are strongly attached to the control surfaces with glue. Check all
pushrod connectors for tightness onto the pushrods. Check all pushrod connector nuts to be sure the
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pushrod connectors will not come loose form the servo arms. Make sure your wing rubber bands are
properly installed and your wing is centered.
Install your propeller. Outside, in a safe area, carefully connect your battery to your airplane. Have an
assistant hold the airplane by the fuselage near the tail. Make sure all spectators are standing behind the
airplane, and run your motor to full throttle for several seconds. If all is well, your airplane is ready to be
presented to your instructor for its first flight.
Performance notes:
The EBT performs best on propellers which have a pitch value ½ of the diameter value, such as 10x5,
11x5.5, or 12x6. Be sure to use a propeller intended for a brushless electric motor, such as a APC Eseries or XOAR PJN prop.
If you are using a TORQUE 2818T-900 or 2814T-820 brushless motor, we recommend using a 12x6 prop
for your first flights. With this prop, if the rest of your system is working correctly, the EBT requires less
than ½ throttle to fly. Full throttle is rarely needed, and the EBT will climb straight up, out of sight, on full
throttle if desired.
After you have successfully completed your training flights and can fly the airplane solo, you may wish to
enhance the performance of your EBT for aerobatics. You can move the balance point back to 3.75
inches and increase the control throws to the following values:
ELEVATOR - 45 degrees up, 45 degrees down
RUDDER - 45 degrees right, 45 degrees left
AILERONS - ½ inch up, ½ inch down
39
Be CAREFUL! The airplane will be very much more responsive with these control throws! Consult your
radio system manual and, if equipped, add 50% exponential to each control function.
ONLY USE THESE AEROBATIC SETTINGS AFTER YOU ARE VERY COMFORTABLE FLYING YOUR
EBT!
After each flying session, check the hardware and control surfaces of your EBT for any looseness or
problems. Inspect your prop for nicks or cuts, and dispose of your prop if you find any. A new prop is
cheap insurance against crashes and injury.
We hope you enjoy your EBT trainer.
Thanks for purchasing this 3DHobbyShop product!
www.3DHobbyShop.com
copyright 2007 3D Hobby Shop
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