Ultra Micro Diablo - 2010/05

by John Glezellis
time to hinge the control surfaces. I “tophinge”
my aerobatic models that are
fabricated from Depron.
On the Ultra Micro Diabolo, it’s
convenient that you can do all of the hinging
at once. To do so, either sand the bottom LE
of the aileron or use a ruler and a sharp #11
X-Acto blade.
For the latter, position the ruler roughly 1/4
inch away from the LE of the surface.
Position the X-Acto blade at an angle so that
it comes in contact with the ruler and the top
of the control surface at the LE, and cut away.
Follow this process for both ailerons and the
elevator.
Once you are satisfied with the bevel,
place the control surface in position and apply
hinge tape centered over the control and
flying surfaces.
When hinging the rudder, it’s easier to
maintain alignment of the rudder hinge line
while the upper and lower vertical fuselage
parts are attached. Cut away the rudder and
cut out only the area where the horizontal
stabilizer will go. Hinge the rudder as
described and cut apart the upper and lower
fuselage parts, which will remain linked and
properly spaced with the rudder hinge.
After you have hinged all of the
components, cut the front fuselage horizontal
cruciform free from the wing LE. Once that is
done, cut a piece of .08mm x 3mm carbon
fiber so it measures the length of the
wingspan.
Lay the wing on a flat surface, and glue
the carbon strip to the wing LE. The carbon
will bend at the center to follow the LE sweep.
The second Diabolo is a fair amount
lighter. It might not seem to be much, but 6/10
ounce is crucial for a model this size and
changes flight performance for the better.
Enough of that; let’s get started.
Look thoroughly at the plans, and note the
materials list and equipment
recommendations. With everything at hand,
building your Ultra Micro Diabolo will go
surprisingly quickly.
Make a copy of the plans. You can use the
copy as a template for cutting all of the
components from 3mm Depron foam, and the
original plans will remain intact. Ask the
AMA Plans Service about the substantial cost
savings of ordering a second copy with your
order.
After you have chosen a flat work area,
lay down a cutting mat, place a piece of
Depron foam on it, and cut away. You might
find it beneficial to tape the plans over the
Depron when cutting each piece, to ensure
that the plans will not move after each cut.
Because of the relatively small size of this
model, the wing, horizontal fuselage
(cruciform), and horizontal stabilizer can be
cut out as one piece of Depron. Always use a
ruler and a sharp #11 X-Acto blade when
making straight cuts.
I advise you to use waxed paper so you
don’t adhere the foam components to your
building surface. And don’t forget to use
foam-safe CA glue.
CONSTRUCTION
Once you have cut all of the parts, it’s
WITH THE INCREASING development
of technology for micro indoor models, I
decided it was time to build a foamie that was
fully 3-D capable and could be flown in the
confined space of an average-size room in a
home. After all, winters here in the Northeast
are long.
After researching various aerobatic
airframes, I chose the Diabolo as the subject.
The full-scale version was designed and built
in Germany. This airplane has gorgeous lines
that make it unique and is capable of
performing some of the most demanding
maneuvers out there.
When I designed the Ultra Micro Diabolo,
I made several changes to its outline to
improve flight performance. I mainly added
area to the wing, horizontal stabilizer, and
fuselage, and I increased the size of the
control surfaces.
When building a model this size, choosing
the proper equipment is critical and is directly
linked to its flight performance. On today’s
market, quite a few companies sell
microservos, motors, speed controllers, etc.
However, what is best for this particular
aircraft?
I constructed two versions of the Diabolo.
One was equipped with “standard” equipment,
and the second was equipped with micro
equipment from E-flite and Spektrum. Take a
look at these models’ specifications and how
they differ.
Model First Diabolo Second Diabolo
Motor C05 brushless 8.5mm coreless
brushed
ESC XP-7a Built into
receiver unit
Servos Three 2.5g Two 1.5g longthrow
linear, as
receiver has two
others built in.
Battery Two-cell, One-cell, 150
200 mAh Li-Poly mAh Li-Poly
Ready-to- 1.8 ounces 1.2 ounces
Fly Weight
38 MODEL AVIATION
05sig2.QXD_00MSTRPG.QXD 3/24/10 1:30 PM Page 38
May 2010 39
Once this is
complete, glue
the front horizontal
fuselage cruciform to the
center and front of this strip.
If you decide that you want to paint your
Diabolo, it is best to do so at this time. If you
are using an airbrush, you can employ craft
paint (which is used for T-shirts, etc.) or any
other paint that is compatible with foam.
When choosing a color scheme, I use card
stock to make paper templates of the
components that are to be painted. Then I
draw the scheme on the templates and use an
X-Acto blade to cut out each color that is to
be painted.
If you do this, use a few ounces of weight
to hold the template in position over the
component that is to be painted and spray
away. Remember that patience is a virtue.
Equipment Installation: Before you
proceed, decide what electronic equipment
you want to put in your little model. As I
described, I tested two setups.
Because of weight, I recommend that you
consider using Spektrum-brand (or similar)
electronics. This build applies to using
Spektrum equipment. If you decide on a
different brand, you might have to modify
the equipment installation process on your
Diabolo because it will differ from the plans.
Make the appropriate cutout in the wing
for the Spektrum AR6400L receiver unit.
Once you have completed that, you can glue
the horizontal cruciform assembly (the
horizontal fuselage pieces, wing, and
horizontal stabilizer) to the vertical fuselage
piece. Use an 18-inch ruler to ensure that the
vertical fuselage is properly aligned and a
plastic 90° triangle to make sure that the
fuselage components are perpendicular to
one another.
Once you have completed the assembly
process, add the tail bracing made from .040
carbon rod. This will ensure that the horizontal
stabilizer will not flex in flight.
It is time to install the landing gear legs
and the wheel pants. To do so, cut two pieces
of .040 carbon rod that measure 41/4 inches in
length. Use sandpaper to sharpen one end of
each rod.
The plans show where the rods will
penetrate both the fuselage side and the wing.
Insert the rods through these locations. Once
you are satisfied with the height of the model
(and make sure it is level), put a few drops of
odorless CA where the carbon makes contact
with the Depron foam.
The plans show the wheel pants and
wheels as one piece. When you cut the wheel
pants, you should have also cut a “half wheel”
to visually simulate a wheel.
This is the lightest method I’ve found to
create wheel pants for a model this size. I
usually paint the “wheel” so it looks as real as
possible.
If you are using this technique, push the
carbon-fiber ends through the wheel pant, in
the same manner for both. Make sure they are
mounted in the same fashion, and glue them in
place.
Insert the motor into the plastic gearbox.
Then insert the entire assembly onto the front
of the airplane. It may be necessary to trim
the front of the aircraft to accept the gearbox
frame.
Once the fit is perfect and the motor is
properly aligned, you can glue in the gearbox
frame with odorless CA. Last, thread the
propeller onto the shaft and use CA to glue
the rubber spinner to the front of the
propeller.
Install the AR6400L receiver unit and the
two wing servos using double-stick servo
tape. Cut a small piece of servo tape that is
slightly smaller than each servo, and place it
on the underside of the servo. Position the
servos according to the plans and properly
secure them.
Regarding the AR6400L, cut two strands
of servo tape (measuring 1/4 x 3/4) and secure
them lengthwise on the top and bottom of the
underside of the unit. Then secure the
AR6400L in place.
When I installed my unit, I plugged the
motor wires to the receiver and ran them on
the underside of the receiver between the two
strands of servo tape. Doing so ensured a
clean installation with respect to wiring.
The pushrods on my model measure 101/8
inches for both the rudder and the elevator. If
you purchased the pushrod set (for the E-flite
Below: The generous amount of fuselage side area
allows maneuvers such as knife-edge flight to require
little rudder input.
Left: Once a pilot gets comfortable with this
model’s flight characteristics, smaller indoor spaces
become an opportunity to enjoy it. Hovering is
possible with a freshly charged battery. This
airplane will accelerate slowly out of a hover.
05sig2.QXD_00MSTRPG.QXD 3/24/10 1:32 PM Page 39
Photos by the author
Above: To create hinge bevels, use a
ruler and a sharp #11 X-Acto blade. Hold
the knife at a 45° angle and pull it slowly
through the material.
Hinge tape, available from Du-Bro, is
used before assembling the two main
airplane sections. The gap between the
upper and lower fuselage halves is
critical.
The E-flite 4-Site gearbox is designed to
interlock with the front of the Diabolo.
Make necessary corrections to ensure a
perfect fit and 0° of up/down thrust as well
as right thrust.
The aileron servo is attached to the control
horn via a pushrod that is included with the
pushrod set from the Micro 4-Site. Servo
tape holds the linear servo in place.
Servo tape is also used to attach the
Spektrum AR6400 control module to the
fuselage. Locations on the plans assure that
the stock radio wiring works without
extensions.
Once the proper CG is located, attach
the single-cell, 150 mAh battery in place
with the included hook-and- loop
material.
Left: All of the components have been
cut from 3mm Depron and the rudder
has been hinged. Use an 18-inch metal
ruler and a sharp #11 X-Acto blade for
clean edges.
Micro 4-Site), you have the necessary
materials to make and complete this assembly.
To start, glue one of the wires with a Zbend
already shaped to the front of the carbon
rod. Slide a piece of heat-shrink tubing over
this assembly and use a heat gun to shrink the
tubing. Repeat this step for the second
pushrod.
If you purchased the hardware set for the
Micro 4-Site, you will notice four pushrod
supports. Two are shorter in height than the
other two.
The shorter supports are for the elevator
pushrod, and they will be secured to the
bottom of the horizontal fuselage cruciform.
The longer supports will be glued on the left
side of the vertical fuselage cruciform. The
plans estimate these locations.
After you insert the rudder pushrod
through two supports, push a piece of heatshrink
tubing over this rod as well. Then glue
another piece of music wire (included in the
pushrod-set package) to the carbon rod.
When the glue sets, push the heat-shrink
tubing over this area and shrink it in place
with a heat gun. Then see where the rudder
40 MODEL AVIATION
05sig2.QXD_00MSTRPG.QXD 3/24/10 1:33 PM Page 40
Shown are two supports for the rudder
pushrod. Those for the elevator are located
below. These supports are included with the
4-Site pushrod hardware kit.
After the motor gearbox is glued in place,
install the propeller and spinner. The
propeller threads in place, and the included
rubber spinner is glued to the front of the
propeller with CA.
The wheel and wheel pant are one unit,
made from 3mm Depron. It’s simple to do
and is durable because of the Diabolo’s
light flying weight.
Type: RC semiscale micro aerobatic
Skil l level: Intermediate
Wingspan: 19 inches
Wing area: 80.75 square inches
Length: 17.356 inches
Weight: 1.2-1.8 ounces
Recommended power system:
E-flite Ultra Micro 4-Site motor and
battery
Const ruct ion: 3mm Depron,
carbon fiber
Finish: Builder’s choice of paint, sticker,
or permanent marker
Radio: Spektrum AR6400 six-channel receiver/ESC/servo system
John designed
the Ultra Micro
Diabolo for fun
3-D flying, but
he also found
that with a
forward CG, it
is also good for
precision
flying.
control horn will mount and make the
necessary Z-bend in the wire, if need be.
Insert one end of the pushrod in the servo
arm (located on the receiver unit) and the other
end on the rudder control horn. Glue the
control horn keeper on the opposite side of the
rudder. Adhere the two supports in place after
making a small cut so that they can each be
inserted in the fuselage side.
Repeat the same process for the elevator
pushrod. However, when gluing in the supports
for the elevator, you will need to glue them on
the underside of the horizontal cruciform.
The aileron pushrods are also included in
this hardware package. Attach one end of the
pushrod to the servo and the other end to a
control horn. Determine where the control horn
will be secured, and make a small cut so that
the control horn can be inserted through it.
Install the small control horn keeper in place
and apply a drop of odorless CA on the top of
the wing. This completes the build.
CG and Rate Settings: The CG should be
110/16-115/16 inches behind the LE of the wing at
the root, depending on personal preference. I
have found that the original rearmost CG is
great for 3-D, but the airplane can lock in better
to perform sequence-style flight with the more
nose-heavy setup. Once you find this CG, use
Velcro to secure the battery pack in place.
Programming this model is relatively easy.
If using the Spektrum 6400L unit, both
aileron servos plug into ports on the receiver
that activate automatically—no mix required.
Regardless, once all the servos are centered, I
recommend that you use the rates and
exponential settings shown on the plans.
I wish you much success with your Ultra
Micro Diabolo, and I hope you enjoy the
construction process and its flight
performance.
Once you fly this model, you will
probably notice that it’s neutral and extremely
predictable. But please remember that weight
is critical—especially on an airplane this size.
Try to keep this model light, to obtain a
ready-to-fly weight of 1.2-1.3 ounces. It has a
fairly wide aerobatic flight envelope, and
because of its petite size, it is sure to turn
heads at the local indoor flying event, or
maybe in your home when the sunroom is
unoccupied. MA
John Glezellis
[email protected]
Sources:
2DogRC
(800) 517-3810
www.2dogrc.com
Du-Bro
(800) 848-9411
www.dubro.com
E-flite
(800) 338-4639
www.e-fliterc.com
JR Radio
(800) 338-4639
www.jrradios.com
Midwest Products
(800) 348-3497
www.midwestproducts.com
Spektrum RC
(800) 338-4639
www.spektrumrc.com
Zap
(863) 607-6611
www.franktiano.com
May 2010 41
05sig2.QXD_00MSTRPG.QXD 3/24/10 2:21 PM Page 41

by John Glezellis
time to hinge the control surfaces. I “tophinge”
my aerobatic models that are
fabricated from Depron.
On the Ultra Micro Diabolo, it’s
convenient that you can do all of the hinging
at once. To do so, either sand the bottom LE
of the aileron or use a ruler and a sharp #11
X-Acto blade.
For the latter, position the ruler roughly 1/4
inch away from the LE of the surface.
Position the X-Acto blade at an angle so that
it comes in contact with the ruler and the top
of the control surface at the LE, and cut away.
Follow this process for both ailerons and the
elevator.
Once you are satisfied with the bevel,
place the control surface in position and apply
hinge tape centered over the control and
flying surfaces.
When hinging the rudder, it’s easier to
maintain alignment of the rudder hinge line
while the upper and lower vertical fuselage
parts are attached. Cut away the rudder and
cut out only the area where the horizontal
stabilizer will go. Hinge the rudder as
described and cut apart the upper and lower
fuselage parts, which will remain linked and
properly spaced with the rudder hinge.
After you have hinged all of the
components, cut the front fuselage horizontal
cruciform free from the wing LE. Once that is
done, cut a piece of .08mm x 3mm carbon
fiber so it measures the length of the
wingspan.
Lay the wing on a flat surface, and glue
the carbon strip to the wing LE. The carbon
will bend at the center to follow the LE sweep.
The second Diabolo is a fair amount
lighter. It might not seem to be much, but 6/10
ounce is crucial for a model this size and
changes flight performance for the better.
Enough of that; let’s get started.
Look thoroughly at the plans, and note the
materials list and equipment
recommendations. With everything at hand,
building your Ultra Micro Diabolo will go
surprisingly quickly.
Make a copy of the plans. You can use the
copy as a template for cutting all of the
components from 3mm Depron foam, and the
original plans will remain intact. Ask the
AMA Plans Service about the substantial cost
savings of ordering a second copy with your
order.
After you have chosen a flat work area,
lay down a cutting mat, place a piece of
Depron foam on it, and cut away. You might
find it beneficial to tape the plans over the
Depron when cutting each piece, to ensure
that the plans will not move after each cut.
Because of the relatively small size of this
model, the wing, horizontal fuselage
(cruciform), and horizontal stabilizer can be
cut out as one piece of Depron. Always use a
ruler and a sharp #11 X-Acto blade when
making straight cuts.
I advise you to use waxed paper so you
don’t adhere the foam components to your
building surface. And don’t forget to use
foam-safe CA glue.
CONSTRUCTION
Once you have cut all of the parts, it’s
WITH THE INCREASING development
of technology for micro indoor models, I
decided it was time to build a foamie that was
fully 3-D capable and could be flown in the
confined space of an average-size room in a
home. After all, winters here in the Northeast
are long.
After researching various aerobatic
airframes, I chose the Diabolo as the subject.
The full-scale version was designed and built
in Germany. This airplane has gorgeous lines
that make it unique and is capable of
performing some of the most demanding
maneuvers out there.
When I designed the Ultra Micro Diabolo,
I made several changes to its outline to
improve flight performance. I mainly added
area to the wing, horizontal stabilizer, and
fuselage, and I increased the size of the
control surfaces.
When building a model this size, choosing
the proper equipment is critical and is directly
linked to its flight performance. On today’s
market, quite a few companies sell
microservos, motors, speed controllers, etc.
However, what is best for this particular
aircraft?
I constructed two versions of the Diabolo.
One was equipped with “standard” equipment,
and the second was equipped with micro
equipment from E-flite and Spektrum. Take a
look at these models’ specifications and how
they differ.
Model First Diabolo Second Diabolo
Motor C05 brushless 8.5mm coreless
brushed
ESC XP-7a Built into
receiver unit
Servos Three 2.5g Two 1.5g longthrow
linear, as
receiver has two
others built in.
Battery Two-cell, One-cell, 150
200 mAh Li-Poly mAh Li-Poly
Ready-to- 1.8 ounces 1.2 ounces
Fly Weight
38 MODEL AVIATION
05sig2.QXD_00MSTRPG.QXD 3/24/10 1:30 PM Page 38
May 2010 39
Once this is
complete, glue
the front horizontal
fuselage cruciform to the
center and front of this strip.
If you decide that you want to paint your
Diabolo, it is best to do so at this time. If you
are using an airbrush, you can employ craft
paint (which is used for T-shirts, etc.) or any
other paint that is compatible with foam.
When choosing a color scheme, I use card
stock to make paper templates of the
components that are to be painted. Then I
draw the scheme on the templates and use an
X-Acto blade to cut out each color that is to
be painted.
If you do this, use a few ounces of weight
to hold the template in position over the
component that is to be painted and spray
away. Remember that patience is a virtue.
Equipment Installation: Before you
proceed, decide what electronic equipment
you want to put in your little model. As I
described, I tested two setups.
Because of weight, I recommend that you
consider using Spektrum-brand (or similar)
electronics. This build applies to using
Spektrum equipment. If you decide on a
different brand, you might have to modify
the equipment installation process on your
Diabolo because it will differ from the plans.
Make the appropriate cutout in the wing
for the Spektrum AR6400L receiver unit.
Once you have completed that, you can glue
the horizontal cruciform assembly (the
horizontal fuselage pieces, wing, and
horizontal stabilizer) to the vertical fuselage
piece. Use an 18-inch ruler to ensure that the
vertical fuselage is properly aligned and a
plastic 90° triangle to make sure that the
fuselage components are perpendicular to
one another.
Once you have completed the assembly
process, add the tail bracing made from .040
carbon rod. This will ensure that the horizontal
stabilizer will not flex in flight.
It is time to install the landing gear legs
and the wheel pants. To do so, cut two pieces
of .040 carbon rod that measure 41/4 inches in
length. Use sandpaper to sharpen one end of
each rod.
The plans show where the rods will
penetrate both the fuselage side and the wing.
Insert the rods through these locations. Once
you are satisfied with the height of the model
(and make sure it is level), put a few drops of
odorless CA where the carbon makes contact
with the Depron foam.
The plans show the wheel pants and
wheels as one piece. When you cut the wheel
pants, you should have also cut a “half wheel”
to visually simulate a wheel.
This is the lightest method I’ve found to
create wheel pants for a model this size. I
usually paint the “wheel” so it looks as real as
possible.
If you are using this technique, push the
carbon-fiber ends through the wheel pant, in
the same manner for both. Make sure they are
mounted in the same fashion, and glue them in
place.
Insert the motor into the plastic gearbox.
Then insert the entire assembly onto the front
of the airplane. It may be necessary to trim
the front of the aircraft to accept the gearbox
frame.
Once the fit is perfect and the motor is
properly aligned, you can glue in the gearbox
frame with odorless CA. Last, thread the
propeller onto the shaft and use CA to glue
the rubber spinner to the front of the
propeller.
Install the AR6400L receiver unit and the
two wing servos using double-stick servo
tape. Cut a small piece of servo tape that is
slightly smaller than each servo, and place it
on the underside of the servo. Position the
servos according to the plans and properly
secure them.
Regarding the AR6400L, cut two strands
of servo tape (measuring 1/4 x 3/4) and secure
them lengthwise on the top and bottom of the
underside of the unit. Then secure the
AR6400L in place.
When I installed my unit, I plugged the
motor wires to the receiver and ran them on
the underside of the receiver between the two
strands of servo tape. Doing so ensured a
clean installation with respect to wiring.
The pushrods on my model measure 101/8
inches for both the rudder and the elevator. If
you purchased the pushrod set (for the E-flite
Below: The generous amount of fuselage side area
allows maneuvers such as knife-edge flight to require
little rudder input.
Left: Once a pilot gets comfortable with this
model’s flight characteristics, smaller indoor spaces
become an opportunity to enjoy it. Hovering is
possible with a freshly charged battery. This
airplane will accelerate slowly out of a hover.
05sig2.QXD_00MSTRPG.QXD 3/24/10 1:32 PM Page 39
Photos by the author
Above: To create hinge bevels, use a
ruler and a sharp #11 X-Acto blade. Hold
the knife at a 45° angle and pull it slowly
through the material.
Hinge tape, available from Du-Bro, is
used before assembling the two main
airplane sections. The gap between the
upper and lower fuselage halves is
critical.
The E-flite 4-Site gearbox is designed to
interlock with the front of the Diabolo.
Make necessary corrections to ensure a
perfect fit and 0° of up/down thrust as well
as right thrust.
The aileron servo is attached to the control
horn via a pushrod that is included with the
pushrod set from the Micro 4-Site. Servo
tape holds the linear servo in place.
Servo tape is also used to attach the
Spektrum AR6400 control module to the
fuselage. Locations on the plans assure that
the stock radio wiring works without
extensions.
Once the proper CG is located, attach
the single-cell, 150 mAh battery in place
with the included hook-and- loop
material.
Left: All of the components have been
cut from 3mm Depron and the rudder
has been hinged. Use an 18-inch metal
ruler and a sharp #11 X-Acto blade for
clean edges.
Micro 4-Site), you have the necessary
materials to make and complete this assembly.
To start, glue one of the wires with a Zbend
already shaped to the front of the carbon
rod. Slide a piece of heat-shrink tubing over
this assembly and use a heat gun to shrink the
tubing. Repeat this step for the second
pushrod.
If you purchased the hardware set for the
Micro 4-Site, you will notice four pushrod
supports. Two are shorter in height than the
other two.
The shorter supports are for the elevator
pushrod, and they will be secured to the
bottom of the horizontal fuselage cruciform.
The longer supports will be glued on the left
side of the vertical fuselage cruciform. The
plans estimate these locations.
After you insert the rudder pushrod
through two supports, push a piece of heatshrink
tubing over this rod as well. Then glue
another piece of music wire (included in the
pushrod-set package) to the carbon rod.
When the glue sets, push the heat-shrink
tubing over this area and shrink it in place
with a heat gun. Then see where the rudder
40 MODEL AVIATION
05sig2.QXD_00MSTRPG.QXD 3/24/10 1:33 PM Page 40
Shown are two supports for the rudder
pushrod. Those for the elevator are located
below. These supports are included with the
4-Site pushrod hardware kit.
After the motor gearbox is glued in place,
install the propeller and spinner. The
propeller threads in place, and the included
rubber spinner is glued to the front of the
propeller with CA.
The wheel and wheel pant are one unit,
made from 3mm Depron. It’s simple to do
and is durable because of the Diabolo’s
light flying weight.
Type: RC semiscale micro aerobatic
Skil l level: Intermediate
Wingspan: 19 inches
Wing area: 80.75 square inches
Length: 17.356 inches
Weight: 1.2-1.8 ounces
Recommended power system:
E-flite Ultra Micro 4-Site motor and
battery
Const ruct ion: 3mm Depron,
carbon fiber
Finish: Builder’s choice of paint, sticker,
or permanent marker
Radio: Spektrum AR6400 six-channel receiver/ESC/servo system
John designed
the Ultra Micro
Diabolo for fun
3-D flying, but
he also found
that with a
forward CG, it
is also good for
precision
flying.
control horn will mount and make the
necessary Z-bend in the wire, if need be.
Insert one end of the pushrod in the servo
arm (located on the receiver unit) and the other
end on the rudder control horn. Glue the
control horn keeper on the opposite side of the
rudder. Adhere the two supports in place after
making a small cut so that they can each be
inserted in the fuselage side.
Repeat the same process for the elevator
pushrod. However, when gluing in the supports
for the elevator, you will need to glue them on
the underside of the horizontal cruciform.
The aileron pushrods are also included in
this hardware package. Attach one end of the
pushrod to the servo and the other end to a
control horn. Determine where the control horn
will be secured, and make a small cut so that
the control horn can be inserted through it.
Install the small control horn keeper in place
and apply a drop of odorless CA on the top of
the wing. This completes the build.
CG and Rate Settings: The CG should be
110/16-115/16 inches behind the LE of the wing at
the root, depending on personal preference. I
have found that the original rearmost CG is
great for 3-D, but the airplane can lock in better
to perform sequence-style flight with the more
nose-heavy setup. Once you find this CG, use
Velcro to secure the battery pack in place.
Programming this model is relatively easy.
If using the Spektrum 6400L unit, both
aileron servos plug into ports on the receiver
that activate automatically—no mix required.
Regardless, once all the servos are centered, I
recommend that you use the rates and
exponential settings shown on the plans.
I wish you much success with your Ultra
Micro Diabolo, and I hope you enjoy the
construction process and its flight
performance.
Once you fly this model, you will
probably notice that it’s neutral and extremely
predictable. But please remember that weight
is critical—especially on an airplane this size.
Try to keep this model light, to obtain a
ready-to-fly weight of 1.2-1.3 ounces. It has a
fairly wide aerobatic flight envelope, and
because of its petite size, it is sure to turn
heads at the local indoor flying event, or
maybe in your home when the sunroom is
unoccupied. MA
John Glezellis
[email protected]
Sources:
2DogRC
(800) 517-3810
www.2dogrc.com
Du-Bro
(800) 848-9411
www.dubro.com
E-flite
(800) 338-4639
www.e-fliterc.com
JR Radio
(800) 338-4639
www.jrradios.com
Midwest Products
(800) 348-3497
www.midwestproducts.com
Spektrum RC
(800) 338-4639
www.spektrumrc.com
Zap
(863) 607-6611
www.franktiano.com
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