AJ Aircraft 2M AJ Acuity User manual

2M AJ Acuity
Assembly Instructions

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Up Your Game! Fly AJ Aircraft
AJ Aircraft thanks you for the purchase of this airplane. Top grade materials and precision assembly have been
used to make this a top quality aircraft. Following the directions closely, will assure you many hours of
thrilling flight. Two years of design, development and testing has gone into this airframe. We hope you’re as
happy with it as we are!
WARNING !
AJ Aircraft’s extensive testing ensures a high quality kit that has gone through many stages to provide you with
a safe, reliable, airframe. Poor assembly will lead to an unsafe model and therefore the instructions must be
followed closely. Should you have any questions, please do not hesitate to contact us. The safe operation of
this model is your responsibility and yours alone. If you are a beginner or have never flown a model of this
size and power you should attempt it with the help of an experienced pilot. This product should not be
considered a toy, but rather a sophisticated, working model that functions much like a full-scale airplane.
Because of its performance capabilities, this product, if not assembled and operated correctly, could cause
injury to you or spectators and damage to property.
This aircraft should be flown in accordance to the AMA safety code. It is highly recommended that
you join the Academy of Model Aeronautics in order to be properly insured and to operate your model at
AMA sanctioned flying fields. If you are not willing to accept all liability for the use of this product please
return if to the place of purchase immediately.
AJ Aircraft does not accept responsibility or liability for damages resulting from use of this product.
Before starting, read through the entire set of instructions to familiarize yourself with the
process.
Additional assembly information can be found in assembly videos on the
AJ-Aircraft YouTube Channel
If there’s ever a question, contact AJ Aircraft. 734-244-4015

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Contents
Contents.................................................................................................................................................................................. 2
Features .................................................................................................................................................................................. 2
Optional Configurations.......................................................................................................................................................... 3
Recommended Items for Completion..................................................................................................................................... 3
Tools Needed .......................................................................................................................................................................... 3
Covering .................................................................................................................................................................................. 4
Wings ...................................................................................................................................................................................... 5
Landing Gear ........................................................................................................................................................................... 9
Fuselage ................................................................................................................................................................................ 11
Rudder................................................................................................................................................................................... 11
Push-Pull Rudder Control.................................................................................................................................................. 11
Pull-Pull Rudder Control.................................................................................................................................................... 12
Elevator ................................................................................................................................................................................. 14
Electric Motor ....................................................................................................................................................................... 16
Cowl & Canopy...................................................................................................................................................................... 17
Radio Installation & Setup .................................................................................................................................................... 19
Features
Specs:
Wing Span - 72"
Length - 78"
AUW - 4800 grams with 1200 gram
batteries (10.5 lbs)
Electric Power –2500-3000 Watt Motor
90amp ESC
2x 5s 5000mah LiPo
Radio - 6 Channel receiver
2 Mini (15x33x27) size Servos (Elevator)
3 Standard (20x40x34) size Servos
(Ailerons & Rudder)
What's in the box:
2M Acuity Airframe
Fiberglass Cowl & Wheel Pants
Carbon reinforced landing gear mount
Pre-hinged control surfaces (not glues)
Removable rudder and stabilizers
Carbon main gear and tail wheel
G-10 control horns
Dual ball links for all connections
Carbon wing tube & stab tube
Cloth wing bags
Light weight foam wheels
Complete hardware package
Genuine Ultracote Covering

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Optional Configurations
You have the option of using a pull-pull rudder servo or a push-pull rudder servo setup. Fasteners, control horns and
servo connecting rods are provided for optional rudder setups.
Recommended Items for Completion
AJ Aircraft AJ5230-20P/205KV 12S
20x13 2 blade prop or 19.5x13 3 blade prop
Jeti Mezon 90HV Lite
(2) x Thunder Power 5s 5000mah LiPo
Futaba BLS171 servos on Ailerons/Rudder
Futaba BLS173 servos on Elevator
(4) x 6" Servo Extensions for the Ailerons and Rx to Wing
(1) x 12" Servo Extension for the ESC to Receiver
(2) x 48" Servo Extension for the Elevator
(7) Servo Connector Safety Clips
3.25" or 82mm Spinner
Tools Needed
Blue Painter’s Masking Tape
Thin CA Glue
30 Minute Epoxy
Denatured Alcohol
Paper Towels
Removable Thread Locker (Loctite 242, Blue)
Metric & Imperial Allen Wrenches
Hobby Knife & Fresh Blades
Covering Iron (Trim Iron)
Clamps
Small Flat File
Electric Drill w/ Assorted Small Bits (1/16”, 5/64”)
Small Flat Blade Screwdrivers
Small Phillips Screwdriver
Sandpaper (150-220 Grit)
Pliers
Measuring Tape & Ruler

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Covering
The covering on your Laser may have developed loose areas through temperature and humidity changes between
manufacturing and shipping. This may also occur during the summer heat. The covering may require retightening a few
times during your first summer of flying.
Take a few minutes to go over all of the seams making sure all edges are secure. Then proceed to shrinking any area
that may need tightening. (Use an iron on all seams. Use a heat gun on open areas and sheeted areas. An iron can be
used in open and sheeted areas but hold the iron slightly above the surface. You don’t want press the covering into the
wood. Using an iron sock will reduce scratches.
Genuine Ultracote covering in 4 color scheme choices:
Red/Blue (True Red HANU866, White HANU870, Midnight Blue HANU885, Silver HANU881)
Yellow/Blue (True Red HANU866, White HANU870, Bright Yellow HANU872, Silver HANU881)
Competition Red (True Red HANU866, White HANU870, Midnight Blue HANU885, Cub Yellow HANU884, Black
HANU874)
Competition Blue (True Red HANU866, White HANU870, Midnight Blue HANU885, Cub Yellow HANU884, Black
HANU874)
At 200-220°F (93-104°C) the adhesive on UltraCote® becomes active
allowing the covering to be attached to the model. While 220° will fully
bond the covering to the model it is well below the temperature that
causes UltraCote® to shrink.
At 300°F (149°C) the initial shrinking of UltraCote® begins.
At 350°F (176°C) UltraCote® reaches its maximum shrinking point.
Raising the temperature above this point will not cause further shrinkage.
Use as little heat as needed. Using too much heat may cause reshrinking
issues later.
Pro Tip - If the iron you're using does not display the actual temperature,
here is a tip that will ensure your iron is properly set.Water boils at
212°F. Allow your iron to warm up at a medium setting. When the iron
reaches its stabilized temperature, carefully pour a few drops of water on
the iron's surface. Adjust the temperature until the water just begins to
boil off. This method is surprisingly accurate and is generally within 10°
(of the exact application temperature of 220).

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Wings
Carefully locate the aileron
servo pocket. Shining a light
through opposite side of the
wing will help highlight the
pocket location. The pocket
is about 10” (255mm) from
the wing root.
Use a new hobby knife blade
to cut though the covering.
Cut from the corners of the
pocket towards the center of
the pocket so the covering can be folded in.
Gently snap off the servo wire installation string (if it’s
attached) and temporarily secure it out of the way. Do
not pull it out of the wing!
Use an iron to seal around the servo pocket. Fold the cut
covering under the wing sheeting and attach it to the
inside edge of the pocket.
Carefully locate the aileron control horn slots. About 4
15/16” (125mm) from the edge of the aileron.)
Use a covering iron to bond the covering in the area the
control horn will sit. Trim the covering away to expose
the slots. Be sure not to cut through to the top side
covering.
The hinges should already be glued into the ailerons.
Give each of them a little pull to ensure they are securely
attached. It’s better to find a loose hinge now rather
than during a flight.
The wings are already slotted for the hinges. Use a
covering iron to secure the covering along the edge of the
wings and ailerons. Look at the wing hinge slots closely.
Make sure the covering will not interfere when gluing the
hinges. Cut away any covering that covers the hinge slot.

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Slip each of the aileron hinges into the wing. Align the
end of the aileron to the wing tip.
Push the aileron tight against the wing closing the gap
between the two of them. Move the aileron to its
maximum desired deflection (About 15°). Notice that the
hinges may pull out slightly. Experiment with the hinge
position finding the best fit before gluing.
Apply a piece of tape next to each hinge. This will help
you locate the hinges when you begin gluing them.
Check the aileron position at the hinges and wing tip
again before gluing.
Start with the hinge near the wing tip. Flex the aileron
slightly and apply a few drops of thin CA glue to one side.
Flex the aileron to its maximum desired position. Then
glue the opposite side.
Close the gap between the aileron and wing to the
desired position at the fuselage end of the wing half. Flex
the aileron slightly and apply a few drops of thin CA glue
to both sides of the hinge. Again, move the aileron back
and forth to check its position. Once the end hinges are
securely positioned you can apply a few drops of thin CA
to both sides of the remaining hinges.
Use the control horns from the “Wings” part bag.

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Use sand paper to roughen the lower portion of the
control horns on both sides. This will help the epoxy
bond to the control horn parts.
Test fit the control horn in the slot. Trim or file the slot as
needed to achieve a snug fit.
The control horn should go in all the way in until the
shoulder contacts the aileron. The linkage hole in the
control horn should be aligned with the hinge centerline.
With the control horn in position apply masking tape
around it. This will help keep excess epoxy off the wing
covering.
Apply epoxy to the slot in the aileron. Use a pin to help
push the epoxy in.
Apply epoxy to the control horn and insert it into the slot.
Wipe away excess epoxy using a paper towel and
denatured alcohol.
Check the alignment along the hinge line as you did when
you test fit the control horn. Reposition as needed.
Allow the epoxy to partially cure. Peel away the masking
tape after the epoxy is securely holding the control horn
in place and still soft enough to easily remove the tape.
Set the wing aside and let the epoxy fully cure.

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With the servo installed mark the mounting hole
locations. Pre-drill for servo mounting screws using a
1/16” drill. Install the servo with the wood screws that
came with your servos. Remove the screws and servo.
Apply a drop of thin CA glue into each mounting screw
hole. This will harden the wood around the screws and
provide a more secure installation. (Allow the CA glue to
dry before reinstalling the servo.)
Connect the servo to a receiver and power supply. Turn
on your transmitter. Set trim and sub trim to zero. Install
a servo arm on the servo about perpendicular to the
servo’s side. Use the transmitter’s sub trim to make it
exactly perpendicular to the side of the servo.
Attach a servo extension and a safety clip to the servo.
Attach the servo wire to the installation string and gently
pull the wire through the wing as you insert the servo
into the wing.
Reinstall the servo.
Thread 2 ball links onto a turnbuckle connecting rod.
Notice that one end of the rod has a right hand thread
and the other end has a left hand thread. Adjust the
length to about 108mm evenly centering the rod
between the ball links. It does not have to be exact. The
turnbuckle allows you to adjust the length while it is
assembled.
Connect a ball link to a servo and the aileron control
horn. Use 2mm socket head screws, flat washers and
nylon lock nuts. (Using a 2mm tap to cut threads into the
servo control horn produces the best connection.) (The
brass ball in the link is offset. The larger reveal side
should be against the control horn.)

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Adjust the position of the aileron to the wing by turning
the turnbuckle. You do not need to disconnect it from
the servo or control horn. (Turn on the transmitter,
receiver and servo while making adjusting to the
connecting rod. This will keep the servo in its correct
position.)
Landing Gear
Landing gear parts bag contents are shown below.
The landing gear screws are supplied installed in the
fuselage. Remove the 6, M4 socket head screws.
Carefully locate the landing gear slot in the side of the
fuselage just below the leading edge of the wing location.
Make a cut in the center of the slot and at the corners.
Use your trim iron to fold and attach the covering into
the slot.
Slip the landing gear through the slot. Notice that there
are right and left hand parts. The landing gear should be
swept back.

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Use 6 flat washers from the landing gear parts bag with
the screws removed earlier to attach the landing gear.
Add a drop of removable thread locker to the screws
during assembly.
File a flat on the wheel axels perpendicular to the axel
wrench flats.
Install a wheel on the axel with a wheel collar. Position
the collar set screw over the flat you filed.
Insert the wheel and axel into the wheel pant, then into
landing gear. Align the wheel pant indentation with the
landing gear. Add a nylon lock nut and tighten.
Install the tail wheel after the rudder installation.
Install the tailwheel using 3 wood screws. Position the
joint of the tail wheel assembly directly over the rudder
hinge line and mark the position of the screws. Turn the
screws into the fuselage and rudder. Remove the screws,
add a drop of thin CA glue to each hole to strengthen the
wood, and reinstall the screws. (Do not fully tighten the
tiller arm screw. The slot in the tiller arm allows the
screw move accounting for any misalignment between
the assembly & rudder.

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Fuselage
Inspect the fuselage for any interior joints that may have
loosened as a result of shipping & handling. Apply thin
CA glue as needed. Apply thin CA glue around the joints
of the fuselage core, firewall, fuselage formers, and
rudder servo tray to strengthen.
At the tail of the fuselage you will find a hole for the
horizontal stabilizer tube, screw holes, alignment pin
holes and a rectangular pocket to access servo wires. Use
an iron to seal the covering around the edges of the
pocket before trimming. Use a new hobby knife blade to
cut though the covering and trim the openings.
There is a servo pocket on each side of the fuselage. This
pocket is intended for a push pull rudder setup. If you
plan to use a pull-pull cable setup DO NOT cut the
pockets open. If you intend to use a push-pull rudder
setup cut open the pocket on either the left or the right.
Rudder
The rudder control can be configured as a push-pull
system or as a pull-pull cable system. See the
configuration options listed on page 3.
Push-Pull Rudder Control
The rudder is built with control horn slots for the push-
pull control system and the pull-pull control system. The
blue masking tape indicates the control horn locations.
The push-pull control horn slots are located near the
bottom of the rudder.

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Remove the rudder by sliding out the hinge pin. Trim the
covering from the control horn slot and follow the same
installation process used for ailerons.
The pull-pull cables can be removed, and the covering will
need to be patched.
Pull-Pull Rudder Control
The rudder is built with control horn slots for the push-
pull control system and the pull-pull control system. The
blue masking tape indicates the control horn locations.
The pull-pull control horn slots are located higher up on
the rudder.
Remove the rudder by sliding out the hinge pin. Trim the
covering from the control horn slot on both sides of the
rudder.
Use sandpaper to roughen up the end of the control horn
so the epoxy will adhere better.
Tests fit the control horns to the slots. Use a file to
modify the slot as needed. The control horn should be
symmetrical about the hinge line. A strait edge laid
across the control horn cable holes should be square to
the rudder centerline.
Apply masking tape around the control horn slot on both
sides of the rudder.
Use 30 minute epoxy to glue the control horns in place.
Check the alignment, peal the masking tape away, and
clean up with alcohol.
Check the alignment again and set aside for the epoxy to
cure. (When setting aside to dry position the rudder and
control horn so gravity does not reposition the control
horn for you.)
Reinstall the hinge pin and rudder onto the fuselage.

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Connect the servo to a receiver and power supply. Turn
on your transmitter. Set trim and sub trim to zero. Install
a servo arm on the servo about perpendicular to the
servo’s side. Use the transmitter’s sub trim to make it
exactly perpendicular to the side of the servo.
Install the rudder servo into the fuselage and pre-drill for
servo mounting screws using a 1/16” drill. Install the
servo with the wood screws that came with your servos.
Remove the screws and servo. (Do not force the screws
into the carbon fiber. The screws may snap. Drill a larger
pilot hole if needed.) Apply a drop of thin CA glue into
each mounting screw hole. This will harden the wood
around the screws and provide a more secure
installation. (Allow the CA glue to dry before reinstalling
the servo.)
Tread the brass cable eyes about half way into the ball
links.
Start the cable assembly at the servo end inside the
fuselage. Thread on 2 crush sleeves and the brass cable
eye. (If you want to cover the connection with heat
shrink tube thread it on the wire first.)
Loop around the cable eye and go back through a crush
sleeve.
Loop around the crush sleeve and back through the
sleeve again. Slide the second sleeve over the tail.
Adjust the loops and crimp the sleeves with the non-
serrated surface of standard plyers.

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Pull the slack out of the cables and make sure the cables
cross once inside the fuselage. Connect the ball links to
the rudder control horn. Use a hole spacing that closely
matches the rudder control horn. (Using a 2mm tap to
cut threads into the servo control horn produces the best
connection.)
Center the rudder in position aligned to the vertical
stabilizer. Clamp a couple of balsa sticks across the
rudder hinge to keep it centered.
Repeat the cable eye installation process on the rudder
end of the cables with the servo powered up and
centered. Pull the cable snug. You don’t need to make
the cable “guitar string”tight.
Remove the clamps and adjust the cable lengths to center
the rudder by turning the cable eyes into the ball links.
Elevator
The elevators are pre-hinged but are not glued.
Slip each of the aileron hinges into the wing.
Apply a piece of tape next to each hinge.
Align the end of the elevator to the wing tip.
Close the gap at the hinge line.
Flex slightly and apply a few drops of thin CA glue.
Trim away the covering over the slot on the bottom side
of the horizontal stabilizer.
Glue the elevator control horn in place using the same
process used to glue the ailerons in position.

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The horizontal stabilizer will hold a 15x33x27mm servo
with 4 mounting screws such as the Futaba BLS173VS.
(Some filing to adjust the servo slot may be needed.)
Add a few drops of thin CA glue around the mounting
holes to harden the wood.
Connect the servo to a receiver and power supply. Turn
on your transmitter. Set trim and sub trim to zero. Install
a servo arm on the servo about perpendicular to the
servo’s side. Use the transmitter’s sub trim to make it
exactly perpendicular to the side of the servo. (Attaching
the servo arm to the servo before installing in the
horizontal stabilizer is typically easier.)
Fold the servo wire towards the top of the servo. Rotate
the servo control horn to fit into the horizontal stabilizer.
Tip the servo so the wired end goes in first.
Thread 2 ball links onto a turnbuckle connecting rod.
Notice that one end of the rod has a right hand thread
and the other end has a left hand thread. Evenly
centering the rod between the ball links.
Connect a ball links to a servo and the elevator control
horn. Use 2mm socket head screws, flat washers and
nylon lock nuts. (Using a 2mm tap to cut threads into the
servo control horn produces the best connection.)
Feed the elevator servo wire extentions through the
fuselage conduit and out the side of the fuselage.
Connect the extension to the elevator servo using a
safetyt clip to secure the connection.

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Slide the carbor fiber horizontal stabilizer tube thought
the fuselage. Then slide on the horizontal stabilizer.
Use a 4-40 socket head cap screw and a flat washer to
secure the stab in position.
Electric Motor
The firewall is pre-assembled with 4mm thread inserts
installed on a 75mm diameter bolt circle.
When using the AJ 5230-20P-205KV motor standoffs are
not needed. However you will need to use the 5mm
shaft spacer that comes with the motor. Bolt the motor
directly to the firewall using 4mm socket head cap screws
and flat washers. Apply a drop of removable thread
locker when installing the motor screws.
If you are using another motor you may need to use
motor standoffs. The cowl length is 3 7/16” (87mm) from
the firewall which will help you plan your motor spacing.
Use nylon zip ties or a hook & loop strap to secure the
ESC to the bottom of the motor box. We recommend
putting a small piece of foam between the ESC and motor
box to dampen vibrations. (62” Acuity shown)

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Cowl & Canopy
The cowl will be mounted using 4 wood screws through
side of the fuselage just in front of the firewall.
Drill a 1/16” hole in the center of the 4 cowl mounting
tabs. Apply thin CA glue the hole to harden the wood
around the hole.
Place tape over the holes and past the front of the
firewall. Use a pin to poke though the tape locating the
mounting hole on the tape. Peal the tape back away
from each hole but leave it attached to the fuselage.
Place the cowl, canopy, and spinner back plate in
position. Center the cowl around the spinner back plate
leaving a clearance gap. Position the cowl with the
fuselage and the canopy. Securely tape the cowl in
position when you’ve found the best possible fit.
Drill a 1/16” hole in the side of the cowl at the locations
marked in the previous step. Do not drill through the
wood tab on the fuselage.
Remove the tape and finish mounting the cowl with
wood screws.
Finish mounting your prop and spinner.

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There are 2 areas in the bottom of the fuselage below the
rudder servo that can be cut open to provide air flow for
motor and speed controller cooling. Use a covering iron
to seal the edges of the areas. Cut through the center of
the covering. Fold it to the inside of the opening and
attach it using a covering iron.
Secure the canopy in position with 3mm socket head cap
screws and flat washers.
Slide the T-Canaliser through the canopy.
Measuring from both sides center the T-Canaliser in the
canopy.
Measure from the horizontal stabilizer on both side and
adjust as needed to ensure that it is parallel with the
horizontal stabilizer.
Tape the T-Canaliser in position when you have found the
perfect position. Remove the canopy and install 3 wood
screws to fasten the T-Canaliser to the canopy.

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The final step for assembly is attaching the wings.
Heat the area around the large slot to attach the
covering. Trim the covering from the slot for access to
the aileron servo wire. There is a hole just forward of the
slot for the wing thumb screw. Trim the covering from
this hole too.
Slid in and center the carbon fiber wing tube.
Slide the wings onto the carbon fiber tube and secure
using the thumb screw.
Radio Installation & Setup
Your receiver can be mounted anywhere in the airframe.
A piece of foam rubber should be used between the
fuselage and the receiver to dampen any vibration.
Use the suggested throws below as your starting point
then fine tune to your flying preferences after your first
few flights.
Take the time to properly balance and trim your aircraft.
The center of gravity range is located from the back edge
of the carbon fiber fuselage support to 10mm back.
To test the CG fly left or right at about 3/4 to full throttle
and pull to a 45 degree up-line. Roll inverted and let go
of the elevator stick. A correct nose heavy CG will slowly
arc to the level. A neutral CG should nearly hold the up-
line. And a tail-heavy CG will steepen the up-line.
While the final setup is of personal preference, these are
some general guidelines to make your first flight a
success.
Control Throws
Elevator
10° Up
13° Down
Aileron
12° Up
12° Down
Rudder
15° Left
15° Right