118 MODEL AVIATION
Also included in this column:
• Robart smoke oil
• News about the author’s
Maverick project
[[email protected]]
Radio Control Jets Jim Hiller
Smaller, faster, and stronger
The start of a final finish on the Maverick turbine conversion
project is applying Flite-Metal aluminum to the wing panels. Final
paint will follow after masking off the aluminum areas.
I just got back from three days at Jets
Over the Heartland in Winamac, Indiana. What
a great time of flying with good friends!
This is an event for fliers, held by fliers, at a
wonderful flying field that a good group of
modelers runs. The site looked great this year, and the
addition to the hangar made model storage convenient.
This is a neat gathering at which you can see the latest
equipment fly—especially Bob Violett’s new electric-powered
jets. And all of you at E-Jets should look out for Rob Lynch. His
fleet of sport, speed, and Scale models continues to grow. He can
fly them well, and he does so often.
This is definitely the year for Jet Central. At Florida Jets the
company rolled out kerosene start on the Super Bee II and Rabbit
turbines, and then the Mammoth hit the skies. Now the next major
product change is out: the new Cheetah.
This is a significant enough product development that Jet
Central is replacing the old standard, its Super Eagle, and the
Falcon because of the Cheetah’s weight and size. It’s the next step
in the evaluation of 30-pound-thrust turbines.
The Cheetah is actually rated at 31 pounds of thrust, yet it
weighs more than a pound less than the Eagle and promises to be
more fuel-efficient. The Cheetah weighs approximately 3.0
pounds, compared with the Super Eagle’s 4.2 pounds and the 3.3-
pound Falcon.
The diameter of the Cheetah is only 4.031 inches, compared
with the Eagle’s 4.37-inch diameter and the Falcon’s 3.89 inches.
The overall length is the major difference with the Cheetah. It’s
9.838 inches with starter, and both the Eagle and Falcon exceed
11.6 inches.
The compact Cheetah is a game changer in size and
performance. I’m looking forward to getting my hands on one.
Another new product I have been using this flying season is
Robart smoke oil. Yeah, that is the company that makes the
retracts and landing gear. This new oil will be distributed through
the normal channels and at hobby shops. So far its price is
comparable to Super-Dry and other smoke oils.
I have burned a couple gallons of the Robart product, and it
has performed great. I have been a dedicated Super-Dry user
because of its performance, but I have found the smoke oil to do
just as well.
The Robart oil is a good, bright white, and it possesses excellent
hang time. Taking into account its ease of availability and equal
performance based on my unscientific testing, I’ll take it.
Maverick Conversion: I have been going slowly on this project
throughout the summer, but progress has not stopped; the model will
soon be ready for paint.
On some areas I am trying an aluminum finish by Flite-Metal.
So far I have found it to be easy to apply. The secret is patience
and care to prevent dirt contamination under the material while
applying it.
Jack Diaz is an incredible modeler. He built these two Top Gun
award-winning jets and flew them as often as most of us fly our sport
aircraft. He put at least 10 flights on each at Jets Over the Heartland.
My model is finished through its final primer layer and has
been finish-sanded with 1,200-grit sandpaper preceding the
application of Flite-Metal. I plan to mask off the aluminum areas
and apply final colors to the model once I have applied and
finished the Flite-Metal.
I will use 3-inch-wide pieces cut to approximately 12 inches in
length, for 10- to 11-inch-long finished panels on the wings. I
tape the material to an old piece of fiberglass and burnish it with a
green 3M scuff pad, to obtain the desired appearance. Then I
clean the foil with alcohol and a tack rag before removing the
backing paper.
The most tedious part is pulling off the backing paper roughly
halfway without kinking the aluminum tape itself. This is done
along the length of the panel.
Once the Flite-Metal is pulled partway back, I clean the
model’s surface again with a tack cloth and then position and
stick the edge. Working approximately 3/4 inch back from the
remaining backing, use a piece of 3/8 square hard balsa to push out
any air bubbles. When that section is firmly in place, pull away
10sig4.QXD_00MSTRPG.QXD 8/20/10 12:40 PM Page 118
the remainder of the backing paper.
Carefully work from the attached foil
with the balsa push block, to secure the
material. Make sure you work that way, to
avoid trapping air bubbles.
Because Flite-Metal is applied one
panel at a time, I take breaks to start the
final rivet-detail application. This is done
by pressing a 1/16-inch-ID brass tube with
the edge sharpened into the foil to leave
rivet impressions. It’s working out nicely
this way and should provide for a cool
finish.
If you want to try this kind of finish, I
strongly suggest that you visit the Flite-
Metal Web site to see the fantastic
instructions. This is an opportunity for me
to try a product I have no experience using,
and so far I like it. It is proving to be far
easier to work with than expected, and it’s
a good way to attain an authentic-looking
aluminum finish.
As I am setting up this Maverick, I’m
thinking about a debate that has been going
on so much lately. What is the right flightpack
battery to use?
If you’ve been reading about this issue,
you know that it is even more important
with Spektrum receivers, which require a
minimum of 3.7 volts. Below that, lowvoltage
detection will cause the receiver to
go into a battery fail-safe condition, which,
by default, lowers the throttle to idle and
all other controls go into a hold mode.
Sometimes the effects are momentary,
and other times they are dreadfully longer.
The message is to choose a battery that
will prevent the fail-safe condition.
There are many battery alternatives. My
T-33 has a five-cell, 1600 mAh Ni-Cd
pack. This is old technology, but it is well
understood.
I tend to be overly cautious in this
situation. I check battery voltage following
charging and before every flight. I never
make more than four flights, because I’ve
learned that my T-33 uses only roughly
200 mAh per attempt. Don’t take a chance
on battery power.
My BobCat has a Spektrum 9100
receiver that has two heavy-duty power
leads, allowing the option of employing
some serious battery power and
redundancy. My battery selection for this
setup is a two-cell, 3700 mAh Li-Poly
leading into a JR 10-amp regulator that
steps up the input to a healthy 6.1 volts.
This battery arrangement has allowed
me to make as many as nine flights without
recharging. And the Li-Poly gets down to
only 7.45 volts—nowhere near its low
limit.
The Maverick and the T-33 weigh
slightly less than 20 pounds each; that’s
lightweight by our jet standards. As an
aircraft’s weight increases, expect more
battery power to be required. That’s where
the advantages of a redundant battery
system can be utilized.
A popular battery system in my area is
a two-cell A123 pack, which provides a
nominal 6.6 volts. Hence no regulator is
required to manage input voltage.
The Maverick will get a 2S1P 2300
mAh A123 pack from ElectroDynamics. I
have the package, complete with the
company’s nano switch rated for an 8-amp
load (item EDC-77N). This battery is light,
at only 6 ounces, and its 10C rating should
be plenty of power for a 16-pound jet.
The one disadvantage is that now it’s
time update to a new battery charger that is
capable of properly charging A123
batteries.
I have included a picture of this
Maverick project, showing some of the
fiberglass parts that I have fabricated for
the conversion.
I am not fond of open inlets with no
ductwork to direct air back to the turbine.
That kind of sloppy installation creates
considerable drag, greatly reducing the
performance of our models. To improve
performance, I produced a simple set of
inlets that will direct air back to and
around the turbine.
The fuel tanks are also shown. They
provide almost 70 ounces of fuel. The
advantage of making your own tanks is
that you can use all of the available space.
I manufactured these parts using the
lost-foam molding technique. Basically I
glued and cut pink home-insulation foam
to the required shape. Shaping the foam for
each piece took roughly one evening. Then I
covered the foam with packing tape, in
preparation for fiberglass.
My rule of thumb for the weight of
fiberglass cloth to use is two layers totaling
close to 10 ounces per yard for inlets and 12
ounces per yard for fuel tanks. So the inlets
are one layer of 4-ounce-per-yard fiberglass
cloth, followed by a layer of 6-ounce-per-yard
fiberglass cloth, and the fuel tanks are two
layers of 6-ounce-per-yard fiberglass cloth.
If you’re interested in doing your own
fiberglass fabrication of parts, research a Web
site. A good one is the RC Universe
composites forum. MA
Sources:
Bob Violett Models
(407) 327-6333
www.bvmjets.com
Jet Central
(941) 423-9931
(941) 468-1246
www.jetcentralusa.com
Robart Manufacturing
(630) 584-7616
www.robart.com
Flite-Metal
16115 Espinosa Dr.
Houston TX 77083
www.flitemetal.com
ElectroDynamics
(734) 422-5420
www.electrodynam.com
RC Universe
www.rcuniverse.com
Jet Pilots Organization
www.jetpilots.org
Jim Hiller
6090 Downs Rd.
Champion OH 44481
Edition: Model Aviation - 2010/10
Page Numbers: 118,119
Edition: Model Aviation - 2010/10
Page Numbers: 118,119
118 MODEL AVIATION
Also included in this column:
• Robart smoke oil
• News about the author’s
Maverick project
[[email protected]]
Radio Control Jets Jim Hiller
Smaller, faster, and stronger
The start of a final finish on the Maverick turbine conversion
project is applying Flite-Metal aluminum to the wing panels. Final
paint will follow after masking off the aluminum areas.
I just got back from three days at Jets
Over the Heartland in Winamac, Indiana. What
a great time of flying with good friends!
This is an event for fliers, held by fliers, at a
wonderful flying field that a good group of
modelers runs. The site looked great this year, and the
addition to the hangar made model storage convenient.
This is a neat gathering at which you can see the latest
equipment fly—especially Bob Violett’s new electric-powered
jets. And all of you at E-Jets should look out for Rob Lynch. His
fleet of sport, speed, and Scale models continues to grow. He can
fly them well, and he does so often.
This is definitely the year for Jet Central. At Florida Jets the
company rolled out kerosene start on the Super Bee II and Rabbit
turbines, and then the Mammoth hit the skies. Now the next major
product change is out: the new Cheetah.
This is a significant enough product development that Jet
Central is replacing the old standard, its Super Eagle, and the
Falcon because of the Cheetah’s weight and size. It’s the next step
in the evaluation of 30-pound-thrust turbines.
The Cheetah is actually rated at 31 pounds of thrust, yet it
weighs more than a pound less than the Eagle and promises to be
more fuel-efficient. The Cheetah weighs approximately 3.0
pounds, compared with the Super Eagle’s 4.2 pounds and the 3.3-
pound Falcon.
The diameter of the Cheetah is only 4.031 inches, compared
with the Eagle’s 4.37-inch diameter and the Falcon’s 3.89 inches.
The overall length is the major difference with the Cheetah. It’s
9.838 inches with starter, and both the Eagle and Falcon exceed
11.6 inches.
The compact Cheetah is a game changer in size and
performance. I’m looking forward to getting my hands on one.
Another new product I have been using this flying season is
Robart smoke oil. Yeah, that is the company that makes the
retracts and landing gear. This new oil will be distributed through
the normal channels and at hobby shops. So far its price is
comparable to Super-Dry and other smoke oils.
I have burned a couple gallons of the Robart product, and it
has performed great. I have been a dedicated Super-Dry user
because of its performance, but I have found the smoke oil to do
just as well.
The Robart oil is a good, bright white, and it possesses excellent
hang time. Taking into account its ease of availability and equal
performance based on my unscientific testing, I’ll take it.
Maverick Conversion: I have been going slowly on this project
throughout the summer, but progress has not stopped; the model will
soon be ready for paint.
On some areas I am trying an aluminum finish by Flite-Metal.
So far I have found it to be easy to apply. The secret is patience
and care to prevent dirt contamination under the material while
applying it.
Jack Diaz is an incredible modeler. He built these two Top Gun
award-winning jets and flew them as often as most of us fly our sport
aircraft. He put at least 10 flights on each at Jets Over the Heartland.
My model is finished through its final primer layer and has
been finish-sanded with 1,200-grit sandpaper preceding the
application of Flite-Metal. I plan to mask off the aluminum areas
and apply final colors to the model once I have applied and
finished the Flite-Metal.
I will use 3-inch-wide pieces cut to approximately 12 inches in
length, for 10- to 11-inch-long finished panels on the wings. I
tape the material to an old piece of fiberglass and burnish it with a
green 3M scuff pad, to obtain the desired appearance. Then I
clean the foil with alcohol and a tack rag before removing the
backing paper.
The most tedious part is pulling off the backing paper roughly
halfway without kinking the aluminum tape itself. This is done
along the length of the panel.
Once the Flite-Metal is pulled partway back, I clean the
model’s surface again with a tack cloth and then position and
stick the edge. Working approximately 3/4 inch back from the
remaining backing, use a piece of 3/8 square hard balsa to push out
any air bubbles. When that section is firmly in place, pull away
10sig4.QXD_00MSTRPG.QXD 8/20/10 12:40 PM Page 118
the remainder of the backing paper.
Carefully work from the attached foil
with the balsa push block, to secure the
material. Make sure you work that way, to
avoid trapping air bubbles.
Because Flite-Metal is applied one
panel at a time, I take breaks to start the
final rivet-detail application. This is done
by pressing a 1/16-inch-ID brass tube with
the edge sharpened into the foil to leave
rivet impressions. It’s working out nicely
this way and should provide for a cool
finish.
If you want to try this kind of finish, I
strongly suggest that you visit the Flite-
Metal Web site to see the fantastic
instructions. This is an opportunity for me
to try a product I have no experience using,
and so far I like it. It is proving to be far
easier to work with than expected, and it’s
a good way to attain an authentic-looking
aluminum finish.
As I am setting up this Maverick, I’m
thinking about a debate that has been going
on so much lately. What is the right flightpack
battery to use?
If you’ve been reading about this issue,
you know that it is even more important
with Spektrum receivers, which require a
minimum of 3.7 volts. Below that, lowvoltage
detection will cause the receiver to
go into a battery fail-safe condition, which,
by default, lowers the throttle to idle and
all other controls go into a hold mode.
Sometimes the effects are momentary,
and other times they are dreadfully longer.
The message is to choose a battery that
will prevent the fail-safe condition.
There are many battery alternatives. My
T-33 has a five-cell, 1600 mAh Ni-Cd
pack. This is old technology, but it is well
understood.
I tend to be overly cautious in this
situation. I check battery voltage following
charging and before every flight. I never
make more than four flights, because I’ve
learned that my T-33 uses only roughly
200 mAh per attempt. Don’t take a chance
on battery power.
My BobCat has a Spektrum 9100
receiver that has two heavy-duty power
leads, allowing the option of employing
some serious battery power and
redundancy. My battery selection for this
setup is a two-cell, 3700 mAh Li-Poly
leading into a JR 10-amp regulator that
steps up the input to a healthy 6.1 volts.
This battery arrangement has allowed
me to make as many as nine flights without
recharging. And the Li-Poly gets down to
only 7.45 volts—nowhere near its low
limit.
The Maverick and the T-33 weigh
slightly less than 20 pounds each; that’s
lightweight by our jet standards. As an
aircraft’s weight increases, expect more
battery power to be required. That’s where
the advantages of a redundant battery
system can be utilized.
A popular battery system in my area is
a two-cell A123 pack, which provides a
nominal 6.6 volts. Hence no regulator is
required to manage input voltage.
The Maverick will get a 2S1P 2300
mAh A123 pack from ElectroDynamics. I
have the package, complete with the
company’s nano switch rated for an 8-amp
load (item EDC-77N). This battery is light,
at only 6 ounces, and its 10C rating should
be plenty of power for a 16-pound jet.
The one disadvantage is that now it’s
time update to a new battery charger that is
capable of properly charging A123
batteries.
I have included a picture of this
Maverick project, showing some of the
fiberglass parts that I have fabricated for
the conversion.
I am not fond of open inlets with no
ductwork to direct air back to the turbine.
That kind of sloppy installation creates
considerable drag, greatly reducing the
performance of our models. To improve
performance, I produced a simple set of
inlets that will direct air back to and
around the turbine.
The fuel tanks are also shown. They
provide almost 70 ounces of fuel. The
advantage of making your own tanks is
that you can use all of the available space.
I manufactured these parts using the
lost-foam molding technique. Basically I
glued and cut pink home-insulation foam
to the required shape. Shaping the foam for
each piece took roughly one evening. Then I
covered the foam with packing tape, in
preparation for fiberglass.
My rule of thumb for the weight of
fiberglass cloth to use is two layers totaling
close to 10 ounces per yard for inlets and 12
ounces per yard for fuel tanks. So the inlets
are one layer of 4-ounce-per-yard fiberglass
cloth, followed by a layer of 6-ounce-per-yard
fiberglass cloth, and the fuel tanks are two
layers of 6-ounce-per-yard fiberglass cloth.
If you’re interested in doing your own
fiberglass fabrication of parts, research a Web
site. A good one is the RC Universe
composites forum. MA
Sources:
Bob Violett Models
(407) 327-6333
www.bvmjets.com
Jet Central
(941) 423-9931
(941) 468-1246
www.jetcentralusa.com
Robart Manufacturing
(630) 584-7616
www.robart.com
Flite-Metal
16115 Espinosa Dr.
Houston TX 77083
www.flitemetal.com
ElectroDynamics
(734) 422-5420
www.electrodynam.com
RC Universe
www.rcuniverse.com
Jet Pilots Organization
www.jetpilots.org
Jim Hiller
6090 Downs Rd.
Champion OH 44481
