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Assembly
of the plane
Instruction
Manual: The ARF I received had no instruction Manuel shipped with
the plane. BME had just started to offer the manual on their web
site for downloading. If you choose to print the manual as I did,
it is fifteen pages long with 102-color photos showing various
assembly steps.
Before
assembly of the plane use your heating iron on medium heat to
remove any wrinkles that might have developed in the covering.
The covering on the plane I received was tight and wrinkle free
which required no ironing.
Joining
the Main Wing
Find
the wing joiner and place the straight edge of the joiner face
down on the table. Place the wing tops facing down on a flat surface.
This is the orientation of how the wing joiner is epoxied into
the slots in both wing halves.
The top of the wing facing down on a flat surface should have
0 degrees dihedral.
Assemble
the wing joiner and wings together, to ensure everything will
fit properly before gluing.
There should be no sizable gap along the entire seam where the
wing halves join. If required, use a hardwood-sanding block to
lightly sand along the seam until the joint is snug.
Now you are ready to glue the wing halves together with 30-minute
epoxy. I glue the wings together in two steps. First I glued the
wing joiner into one half of the wing and let it cure over night.
I then glue the wing half's together.
Align the wing halves along the joint before the epoxy sets up.
Gluing in two steps allows you more time for alignment and cleanup
rather than trying to mix and glue it all in one shot.
I used nylon band clamps and a quick clamp to hold the wing halves
together after gluing. Wipe off all excess epoxy with rubbing
alcohol and rags. Make sure alignment of the joint is even and
that the wing remains flat and straight with the top surface of
the wing facing down.
Cut away the covering over the holes and epoxy the wing holding
dowels into the front of the wing.
Find the wing holding plate. Then remove the covering film on
one side. Draw a centerline on the other side. Mount the plate
centered on the wing bottom, aligning the holes for the wing bolts.
Once alignment is achieved, draw a line around the wing plate
on to the wing. Remove the covering on the wing 1/8" in from
the lines you drew for gluing of the wing plate. Use CA or epoxy
to mount the wing plate to the wing.
Next,
mount the wing to the fuselage. Find the wing belly pan and cut
away the covering over the two holes for the wing bolts. Set the
belly pan on the wing aligning both ends with the fuselage. Check
for proper fit and seating. If needed, sand or cut the sides of
the belly pan until it sits tight against the profile of the wing.
After proper alignment is achieved mark both sides of the belly
pan where it meets the wing and
set it aside.
Remove the wing from the fuselage. Remove the covering just inside
the lines you drew for the belly pan. Be careful to cut only the
covering only and not the balsa.
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Optional:
For personal preference and added strength, I fiber-glassed
the bottom of the wing joint. The fiberglass will be hidden
with the installation of the belly pan.
Cut a strip of fiberglass wide enough to not interfere with
the installation of the belly pan and long enough to go across
the joint.
Mix 30-minute epoxy and put a thin coat on the wing joint
wide enough to imbed the fiberglass strip.
Next coat the fiberglass strip until both side are totally
covered in epoxy then apply it on top of the wing joint. Work
the fiberglass flat onto the wing working out any air pockets
that might develop. Dipping your fingers lightly in rubbing
alcohol will help you flatten out the fiberglass without lifting
it every time you raise your fingers. Smooth everything out
and let it set overnight. |
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Remount
the wing and realign the belly pant. If everything looks good
you can now mount the belly pant to the wing. Use medium CA
to glue it into place. Be careful not to glue the front or
rear part of the belly pant to the fuselage.
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Tail installation
With
the wing temporarily installed on the fuselage, trial fit the
horizontal stab, vertical fin, elevators, rudder and stab wedges
for proper alignment. Make sure the horizontal stab and elevators
are centered and equal distant to the trailing edge of the wing
tips.
Once everything is in proper alignment you can now mark for the
removal of the covering of the stab and vertical fin. After removal
of the covering install and realign the stab and fin for gluing.
Make sure the vertical fin and horizontal stab are square to each
other. Also make sure that the surface of the horizontal stabilizer
is parallel to the surface of the wing and the outside tips of
the stabilizer are equaled distant to the outside wing tips. Now
apply thin ca to hold everything in place.
Optional:
I installed tail wires to give additional support to the horizontal
stabilizer and vertical fin.
Landing
gear assembly
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Install
the tail wheel bracket to the back of the fuselage.
Gather all the parts for the assembly of the landing gear.
First mount the axles to the landing gear. Note: I ended
up replacing the axles. As I was installing the axles for
the landing gear the threaded part separated from the axle
shaft while I was attempting to snug it up.
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Next
cut a 3/16" piece of fuel tubing and slide it on the axle
to the root. Then install the wheel and collar onto the axle.
Note: The wheels supplied with the ARF were so out of round
I replaced them with a set of new ones.
Install
the landing gear onto the to fuselage. Cut a slot in the bottom
of the wheel pants centered with the holes to slide over the axle.Set
the plane right side up on the floor or bench.
Now you can slid the wheel pants over the axle and set the bottom
or flat portion of the wheel pants parallel to the ground. While
the wheel pant is parallel to the ground drill the holes through
the landing gear into the wheel pant to receive the tee nuts.
Remove the pant, installation of the tee nuts and reinstall the
pant. It is a good practice to use thread lock the bolts to prevent
them from coming loose.
Installation
of the control surfaces
The
ARF comes with CA hinges, which are perfectly fine to use and
easy to install.
The CA hinges are installed by first placing two pins in the center
outer edges of each hinge. Install the CA hinges in one side of
the control surfaces slots, butting the pins up to the hinge line,
and then install the control surface with the hinges into the
other joining half. The pins will prevent the hinges from being
pushed to far into either side of the control surface or fuselage.
Once
every thing looks good you can then remove all pins. Manually
apply the desired surface deflection you wish to achieve to all
surfaces. This is done to make sure your hinge line gap isn't
to tight preventing the maximum deflection you are tiring to achieve
prior to gluing.
Its best to have the hinge line with virtually no gap to prevent
flutter, but it does no good if that gap prevents you from achieving
the deflection needed if you plan on doing 3D.
I make sure I can get the deflection I'm looking for. Then after
the all the hinges have been glued, I seam seal both sides of
the hinge line gap with a strip of clear thin ultracote. This
prevents flutter, while being able to achieving full surface deflection.
Optional
Nylon Hinge Installation
I
prefer to install nylon pinned hinges for all of my 3D planes.
The nylon pinned hinges are definitely more work to install but
are worth the time and effort to me. This requires a thicker slot
in both surfaces to receive the nylon hinges. I found using a
hacksaw blade is the easiest way for me to achieve this. I carefully
slide the hack saw blade into the slot being careful not to push
material into the wing cavity that will move around and rattle.
Once the saw blade is through, I remove material as I pull the
saw blade out. You are basically sawing out the material only
when you pull the saw blade out. The width of the saw blade is
perfect for receiving nylon hinges. If the slot is not thick enough
for the hinge you are installing you can slightly bevel the saw
blade on the out stoke to remove more material.
Once you have all of the slots cut, dry fit the hinges and control
surfaces to make sure all your hinges seat properly to minimize
any problems during gluing.
Next you need to lubricate the barrel of the hinges so that the
glue does not bind them.
You could use light oil, but I protected the knuckle of the hinges
in a different way. I heat up some petroleum jelly in a small
can (like a tuna fish can). I do this by placing the can on top
of my sealing iron at medium heat until the petroleum turns liquid.
I
then fold the hinges 45 degrees and dip the knuckle of each hinge
into the liquid petroleum.
Be sure to dip only the knuckle and not the gluing surface. The
petroleum flows around the entire pin protecting it from the glue.
Set them aside to allow the petroleum to gel before gluing into
the control surfaces and airframe.
I
glue the hinges at the control surfaces in two steps. I first
epoxy all the hinges into the Main wings, horizontal stabilizer
and vertical fin using 30-minute epoxy. After I am satisfied that
the hinges are seated properly and the knuckle of the hinge is
parallel to the hinge line, I clean up any epoxy then allow overnight
curing. The next day I finish gluing the control surfaces of the
ailerons, elevator and rudder to the other half of the hinges.
Installing
control linkages
Cut
out the covering in the location for the servo installation of
the wing, elevators and rudder. A Pull-Pull setup was used for
the Rudder control, which is mounted under the wing in the fuselage
servo tray.
Install
the two aileron servos. Make a temporary mark that is square with
the hinge line of the wing to the outermost hole on the servo
arm. Install the control horns centered on this mark. Center the
holes on the control horn with center of the hinge line while
the aileron is in neutral position.
The
two elevator servos I used are Hitec digital 6635 HB. Hitec digital
servos allow you to use a Hitec programmer to individually set
the servo throws (EPA) and neutral to exactly the same position
so that the elevator deflection on high rates is exactly the same
point in both directions. The servos were then connected to a
Y- harness and plugged into channel 1.
While
screwing in the elevator servo on the right side of the plane,
the plywood mounting plate came loose and broke away from the
fuselage. Luckily no damage occurred to the rest of the plane
and did require re-epoxing the plate back into place
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The
throttle servo is installed in the fuselage servo tray under
the wing |
NOTE:
Before hookup of the linkages, I first set the Transmitter trims
and sub-trims to the zero or neutral position for the Ailerons,
Rudder and elevator.
The servo arm should end up 90 degrees to the body of the servo
while the servo is in its neutral position. If needed, remove
the servo arm and manually adjust it to be as close to 90 degrees
as possible.
Then use your sub trims to fine-tune the servo arms to 90 degrees.
Hookup your linkages while the servos and control surfaces remain
in their neutral position. Mechanically adjust the clevises until
all control surfaces remain neutral.
Engine
Installation
The
placement of the cowl from the firewall required the Magnum 120
to be installed as close to the firewall as possible.
The
supplied motor mount prevented the installation of the engine
that close to the firewall so another mount I had lying around
was used.
The firewall has right thrust built into the fuselage. You will
need to offset the mounting of the engine on the firewall so the
prop shaft exits the center of the cowl. The engine was mounted
sideways to prevent the muffler from exiting the side of the cowl.
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The
manual called for the face of the cowl to be 5 ½"
out from the firewall. I set the cowl 5-1/8"out which
seemed to hug to fuselage better.
The cowl was mounted using the supplied hardware. Blind nuts
are already installed in the firewall for the cowl attachment.
I also used rubber O-rings under the washers for the screws
that mount the cowl. The rubber O-rings prevent the screws
from vibrating loose during flight.
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With
the 120-size engine I opted to use a larger 16oz fuel tank. I
mounted the fuel tank over the CG on two carbon fiber rods that
were epoxied across the sides of the fuselage to form a support
rail for the tank. Foam padding was installed under the tank where
it sat on the carbon fiber rods. Tie straps were used to hold
the tank to the support rails.
Here is a picture of the mounting of the fuel tank, throttle,
rudder servos, and the receiver in the fuselage.
Battery switch and fuel dot were side mounted to the fuselage.
To
balance the plane to a 4-3/4 CG, The battery had to be moved 3"
behind the trailing edge of the wing. This required cutting a
hatch in the bottom of the fuselage to secure the battery on mounting
rails that I epoxied into place. The battery was then set in a
foam bed and tie strapped to the rails. The hatch was made removable
and held in place with a couple of small screws.
A
volt watch was added to the cockpit, which constantly gives you
a visual LED read out on the readiness of your receiver battery.
It plugs into any unused channel on your receiver.
Graphics
Apply
the supplied graphics to the wings and fuselage. Note: Avoid,
using a heating iron over the "Cap Maniac" and "BME
Aircraft" decals. They tend to buckle and deform under direct
heat from the iron.
Setup
Initial setup is as follows: Deflection was measured at the outmost
points of the Rudder and elevator. Aileron deflection was measured
closest to the fuselage. Triple rates were set up on elevator.
Rates:
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High
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Medium
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Low
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| Ailerons |
1-3/4"
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¾"
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| Elevator |
2-7/8"
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1-7/8"
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1-1/8"
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| Rudder |
5-3/4"
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2-3/4
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