Also included in this column:
• Contra-rotating propeller
unit
• Twisted fuselage frame fix
• Octavian’s Pfalz
• Herr Cub on floats
• Bob Mattes head for Cox
.020.
• Diels Engineering’s new Web
site
• Paul Bradley’s Model Airplane
Web site
[[email protected]]
Free Flight Sport Gene Smith
Gas model one design for 2009 Nats
Bob Stalick, former NFFS president, with his 1/2A Spacer: the 2009
Nats NFFS one-design event model. Stalick photo.
Keith Sterner’s beautiful and efficient contrarotating propeller
units are for sale by Klass Wings, LLC. Hallman photo.
Above: John Houck’s A2D
Skyshark, Dallas Cornelius’s
Martin Baker MB-5, and
Tom Hallman’s winning
Koolhoven use the Sterner
unit. Hallman photo.
Left: The Germans had
some beautiful paint schemes
for their airplanes, as
documented for Octavian
Aldea’s Pfalz. Hallman photo.
THE GAS MODEL for the NFFS
[National Free Flight Society] One Design
event at the 2009 Nats will be Sal Taibi’s
1/2A Spacer. Bill Vanderbeek will give
every participant a nice certificate with a
three-view of the model that John
Anderson drew.
As you can see in the photo, Bob
Stalick will be ready with his Spacer. The
beautiful site in the background is a grass
seed field 15 miles south of Albany,
Oregon.
Bob’s Spacer is equipped with a Wen-
Mac engine and a Tatone pinch-off timer.
An alternative to the Tatone is the Texas
January 2009 129
01sig5.QXD 11/24/08 12:48 PM Page 129
MICRO I from Texas Timers.
Bob feels that the best engine choice is
probably the Cox reed valve. He thinks the
Cox Medallion’s additional power would
make the Spacer more difficult to trim.
He suggests that anyone who is planning
to use a Medallion or similar engine use a
small (1/8 x 1/8 inch) top spar placed roughly
one-third of the way behind the wing LE.
The event rules allow that type of
modification, and it will give the wing more
stiffness and strength.
Bob originally trimmed the Spacer to fly
right under power and left in the glide.
More recent trimming procedures have the
model flying to the right for both power and
glide.
The current trim setup has 2° of
downthrust and 2° of left thrust. The rightwing
main panel is washed in 1/16-3/32 inch.
A bit of left rudder tab may be needed. Tilt
the stabilizer with the right side high for a
right turn in the glide. That should give you
a starting point for trimming.
Plans for the 1/2A Spacer are available
from the NFFS Plans Service. Plans and
short kits are available from Campbell’s
Custom Kits. It’s not too soon to start your
model. Nostalgia-legal .049 or .051 engines
are required.
Contra-rotating Propeller Unit: Keith
Sterner developed a new contra-rotating
propeller system that proved to be
extremely successful at last year’s FAC
[Flying Aces Club] Nationals. He had been
thinking about these little “CRPD” units for
a long time.
An E-mail that Tom Hallman sent out to
many of his friends early last year stirred
Keith into action. He saw the project as a
challenge.
Keith produced a rough working
prototype using a small plastic tube from a
glitter container, front and back plates of
1/16 birch plywood, and aluminum-tubingshaft
bushings. The gears were platedbrass
slot-car pinions.
That prototype was successful, so
Keith, Tom, and John Houck got together
in Keith’s workshop to share ideas about
the possibilities of the design, and the
project was born.
Keith refined the design and built the
second prototype, which he presented to
Tom and John. They agreed that the unit
was on the right track. Keith built the third
version, which Tom installed in his
Koolhoven and flew to a win at the FAC
Nats in Geneseo, New York, this past July.
John received the first large unit that
incorporated all that Keith had learned
while fabricating the small units. He
installed it in his A2D Skyshark and
finished in second place at Geneseo.
The small drive measures .750 inch
long, .720 inch wide, and .458 inch high,
and it uses a .032-inch-diameter-musicwire
propeller shaft. The large drive
measures 0.781 inch long, 1.438 inches
wide, and 0.917 inch high, and it uses a
.062-inch-diameter-music-wire propeller
shaft.
Customers can swap out the main
music-wire shaft for an equal-size shaft—
.032 or .062—they prefer that has the
hook shape they prefer. The units are
supplied with the standard diamond hook
shape.
132 MODEL AVIATION
Each unit includes documentation that
covers preparation, installation, and
maintenance. Installation covers the
preferred mounting, securing the main
shaft to the drive shaft, and altering the
main (music wire) and secondary (brass)
shafts to accommodate any length other
than the standard as supplied, which may
be required for a particular model. A
documentation sheet supplied with each
unit contains an actual-size four-view
drawing of it and the full-scale mounting
pattern.
The small gear-drive unit weighs 3
grams, and the large weighs 7 grams. The
small unit was designed to handle models
spanning as much as 20 inches, and the
large unit is for models spanning as much
as 30 inches.
The small units are in full production
and are priced at $40 each plus shipping
and handling. The large units are priced at
$50 each plus shipping and handling.
Contact Keith Sterner at Klass Wings; see
the “Sources” list for the addresses.
Twisted Fuselages: This may never have
happened to you, but it seems to happen to
me often when I build box fuselages for
my rubber-powered Scale models.
Let’s say I know I made the fuselage
sides identical. I pinned them to a flat
board and secured them with right-angle
fixtures when I added the first crossbraces.
I carefully checked the fuselage alignment
as construction proceeded. Then I took the
structure off the board.
As I sighted along the fuselage to
confirm the beautiful, straight structure,
arrrggh! The wing-mount area was twisted
1/64 inch. That is just enough to put an
unwanted twist in the wing. How could
that happen? I don’t know, but at least I
figured out an easy way to fix it.
I use a MonoKote heat gun to take
warps out of wings, so I figured that there
was a chance it might work to adjust the
fuselage. Sure enough, it worked like a
charm!
Keep the fuselage moving over the heat
to avoid damage. Twist the structure as
needed to correct the misalignment. This
won’t turn a “pig’s ear into a silk purse”;
however, if the misalignment is minor, this
is an effective way to get the fuselage
framework straight.
I use Titebond to frame fuselages. That
may explain why the heat technique
works. I have not tried it with
cyanoacrylate.
Octavian Aldea built a beautiful Pfalz
from DPC Models’ laser-cut kit. It spans
18 inches and uses two 14-inch loops of
1/8-inch FAI Tan rubber. Octavian found
that the supplied loop of 3/16-inch rubber
left the airplane a bit underpowered.
The Pfalz weighs 35 grams without
rubber and uses a 6-inch Peck-Polymers
propeller. At that weight, it might benefit
AMA Academy of Model
Aeronautics
ARF Almost Ready to Fly
BEC Battery Eliminator Circuit
CAD computer-aided design
cc cubic centimeter
CD contest director or
compact disc
CG center of gravity
CL Control Line
cm centimeter
cu. in. cubic inch
DT dethermalizer
EPP (foam) expanded polypropylene
ESC Electronic Speed Control
FAI Fédération Aéronautique
Internationale
FCC Federal Communications
Commission
FF Free Flight
GHz gigahertz
Kv rpm/volt
kV killivolt (1,000 volts)
LCD Liquid Crystal Display
LE leading edge
LED light-emitting diode
Li-Poly Lithium Polymer
mA milliamperes
MA Model Aviation
mAh milliampere-hours
MHz megahertz
mm millimeter
Nats AMA Nationals
Ni-Cd Nickel Cadmium
NiMH Nickel Metal Hydride
RC Radio Control
rpm revolutions per minute
RTF Ready to Fly
SASE self-addressed, stamped
envelope
SIG Special Interest Group
TE trailing edge
Model Aviation’s
Frequently Used
Abbreviations /Acronyms
from two loops of 3/16-inch rubber.
Octavian covered the model with white
Esaki tissue. The markings are also tissue,
including the red heart and black arrow.
The Pfalz was finished with two coats of
nitrate dope before the markings were
applied. A final coat of clear nitrate dope
was applied to protect and bond the
markings.
The only problem Octavian
encountered during trimming was a degree
of lateral instability, indicated by the
airplane’s tendency to recover slowly
from a lateral wind gust.
At Wawayanda, New Jersey, this fall,
Octavian had the privilege of chatting
with a few great modelers, including
Vance Gilbert. He is extremely
experienced with and accomplished at
flying biplanes.
After watching the Pfalz fly, Vance
advised Octavian to increase the dihedral
on the upper wing from 0, as prescribed in
the kit, to roughly 1 inch. He also suggested
increasing the lower wing dihedral from 0
to 3/4 inch. Thanks to Vance, the lateralinstability
issue was solved.
Octavian made the preceding
modifications in the motel room at
Wawayanda before the second day of
competition. Ronny Gosselin supervised
and encouraged him, making sure that
Octavian finished the modification before
the second competition day. The best
flight so far is 21 seconds, but the model
is showing promise.
You can find DPC laser-cut kits for
several World War I airplanes on the Web
site. See the “Sources” list for contact
information. Several DPC kits, including
the Pfalz, are no longer listed on the DPC
Web site, because they are being updated
with new CAD plans and lighter
structures.
The updated kits will be released as
they become available. However, if you
want one of the older kits now, you can
get one. In addition, two nice Albatros
pseudo Dime Scale kits are currently
available. E-mail DPC Models for a list
and pricing.
In an accompanying photo, Bob
Schlosberg’s Herr Super Cub on floats
shows off its classic lines. Bob made some
modifications to the kit, even adding a
paddle on the inside of the right float. He
also slightly modified the rudder’s shape
to match the picture he has of the fullscale
aircraft.
Many hobby shops carry the Herr kits.
If you can’t find one there, check out Penn
Valley Hobby Center.
I have always liked the Fairchild 22’s
lines but have been hesitant to build one.
Parasol-wing configurations are known to
have less lateral stability than high-wing
cabin models. Bob Schlosberg decided to
build one despite that knowledge.
He started with Paul Lindberg
Fairchild 22 plans for a 16-inch-span
01sig5.QXD 11/24/08 1:12 PM Page 132
model. Bob enlarged the plans to produce a
26-inch wingspan, and he could not be
more pleased with the results. He reports
that the model is an excellent flier, even
with the scale dihedral.
Bob Mattes has an engine-rework
service for FF and CL power plants. He
has done a lot of work making Nelsonplug-
compatible heads for nostalgia-era
engines.
Bob recently developed a replacement
glow-head adapter for the Cox .020 Pee
Wee and Tee Dee engines. It costs
approximately the same as one would
pay for two of the increasingly rare Cox
.020 plugs on eBay.
Because of the tolerances involved,
Bob advises letting him make a custom
fit to your engine for best performance.
You can contact him via E-mail. See the
“Sources” list for the address.
Replacement Glow Bee plugs that
work with Bob’s adapter are roughly $4
each. They are available from Larry
Driskill through Kitting It Together. See
the “Sources” list for contact
information.
Diels Engineering, which sells great
Scale FF rubber-powered kits, has a new
Web site. See the “Sources” listing for
contact information.
Paul and Ralph Bradley’s Model
Airplane Page is one of my favorite Web
sites. While there last fall, I found that
several models had been added since my
previous visit. There are free downloads
for many neat World War II No-Cals, as
well as printing patterns that allow you
to re-create your own Jigtime and
Goldberg sheet-balsa flying models.
Don’t miss the tips and references
section. There are also micro-size and
electric-powered RC models for those
who enjoy that aspect of our hobby.
Visiting this site is a must. MA
Sources:
Texas Timers
(423) 282-6423
www.texastimers.com
NFFS Plans Service
(678) 242-8655
www.freeflight.org/store/plans/plans.htm
Campbell’s Custom Kits
(765) 389-1749
www.campbellscustomkits.com
Keith Sterner (Klass Wings, LLC)
4019 Nicholas St.
Easton PA 18045
[email protected]
DPC Models
1003 Sunset Tr.
Kingston Springs TN 37082
http://dpcmodels.homestead.com
Penn Valley Hobby Center
(215) 855-1268
www.pennvalleyhobbycenter.com
Mattes Engine Service
[email protected]
Kitting It Together
www.kittingittogether.com
Diels Engineering
Box 263
Amherst OH 44001
http://dielsengineering.samsbiz.com
Paul and Ralph Bradley’s Model Airplane
Page
www.parmodels.com
Edition: Model Aviation - 2009/01
Page Numbers: 129,130,132,135
Edition: Model Aviation - 2009/01
Page Numbers: 129,130,132,135
Also included in this column:
• Contra-rotating propeller
unit
• Twisted fuselage frame fix
• Octavian’s Pfalz
• Herr Cub on floats
• Bob Mattes head for Cox
.020.
• Diels Engineering’s new Web
site
• Paul Bradley’s Model Airplane
Web site
[[email protected]]
Free Flight Sport Gene Smith
Gas model one design for 2009 Nats
Bob Stalick, former NFFS president, with his 1/2A Spacer: the 2009
Nats NFFS one-design event model. Stalick photo.
Keith Sterner’s beautiful and efficient contrarotating propeller
units are for sale by Klass Wings, LLC. Hallman photo.
Above: John Houck’s A2D
Skyshark, Dallas Cornelius’s
Martin Baker MB-5, and
Tom Hallman’s winning
Koolhoven use the Sterner
unit. Hallman photo.
Left: The Germans had
some beautiful paint schemes
for their airplanes, as
documented for Octavian
Aldea’s Pfalz. Hallman photo.
THE GAS MODEL for the NFFS
[National Free Flight Society] One Design
event at the 2009 Nats will be Sal Taibi’s
1/2A Spacer. Bill Vanderbeek will give
every participant a nice certificate with a
three-view of the model that John
Anderson drew.
As you can see in the photo, Bob
Stalick will be ready with his Spacer. The
beautiful site in the background is a grass
seed field 15 miles south of Albany,
Oregon.
Bob’s Spacer is equipped with a Wen-
Mac engine and a Tatone pinch-off timer.
An alternative to the Tatone is the Texas
January 2009 129
01sig5.QXD 11/24/08 12:48 PM Page 129
MICRO I from Texas Timers.
Bob feels that the best engine choice is
probably the Cox reed valve. He thinks the
Cox Medallion’s additional power would
make the Spacer more difficult to trim.
He suggests that anyone who is planning
to use a Medallion or similar engine use a
small (1/8 x 1/8 inch) top spar placed roughly
one-third of the way behind the wing LE.
The event rules allow that type of
modification, and it will give the wing more
stiffness and strength.
Bob originally trimmed the Spacer to fly
right under power and left in the glide.
More recent trimming procedures have the
model flying to the right for both power and
glide.
The current trim setup has 2° of
downthrust and 2° of left thrust. The rightwing
main panel is washed in 1/16-3/32 inch.
A bit of left rudder tab may be needed. Tilt
the stabilizer with the right side high for a
right turn in the glide. That should give you
a starting point for trimming.
Plans for the 1/2A Spacer are available
from the NFFS Plans Service. Plans and
short kits are available from Campbell’s
Custom Kits. It’s not too soon to start your
model. Nostalgia-legal .049 or .051 engines
are required.
Contra-rotating Propeller Unit: Keith
Sterner developed a new contra-rotating
propeller system that proved to be
extremely successful at last year’s FAC
[Flying Aces Club] Nationals. He had been
thinking about these little “CRPD” units for
a long time.
An E-mail that Tom Hallman sent out to
many of his friends early last year stirred
Keith into action. He saw the project as a
challenge.
Keith produced a rough working
prototype using a small plastic tube from a
glitter container, front and back plates of
1/16 birch plywood, and aluminum-tubingshaft
bushings. The gears were platedbrass
slot-car pinions.
That prototype was successful, so
Keith, Tom, and John Houck got together
in Keith’s workshop to share ideas about
the possibilities of the design, and the
project was born.
Keith refined the design and built the
second prototype, which he presented to
Tom and John. They agreed that the unit
was on the right track. Keith built the third
version, which Tom installed in his
Koolhoven and flew to a win at the FAC
Nats in Geneseo, New York, this past July.
John received the first large unit that
incorporated all that Keith had learned
while fabricating the small units. He
installed it in his A2D Skyshark and
finished in second place at Geneseo.
The small drive measures .750 inch
long, .720 inch wide, and .458 inch high,
and it uses a .032-inch-diameter-musicwire
propeller shaft. The large drive
measures 0.781 inch long, 1.438 inches
wide, and 0.917 inch high, and it uses a
.062-inch-diameter-music-wire propeller
shaft.
Customers can swap out the main
music-wire shaft for an equal-size shaft—
.032 or .062—they prefer that has the
hook shape they prefer. The units are
supplied with the standard diamond hook
shape.
132 MODEL AVIATION
Each unit includes documentation that
covers preparation, installation, and
maintenance. Installation covers the
preferred mounting, securing the main
shaft to the drive shaft, and altering the
main (music wire) and secondary (brass)
shafts to accommodate any length other
than the standard as supplied, which may
be required for a particular model. A
documentation sheet supplied with each
unit contains an actual-size four-view
drawing of it and the full-scale mounting
pattern.
The small gear-drive unit weighs 3
grams, and the large weighs 7 grams. The
small unit was designed to handle models
spanning as much as 20 inches, and the
large unit is for models spanning as much
as 30 inches.
The small units are in full production
and are priced at $40 each plus shipping
and handling. The large units are priced at
$50 each plus shipping and handling.
Contact Keith Sterner at Klass Wings; see
the “Sources” list for the addresses.
Twisted Fuselages: This may never have
happened to you, but it seems to happen to
me often when I build box fuselages for
my rubber-powered Scale models.
Let’s say I know I made the fuselage
sides identical. I pinned them to a flat
board and secured them with right-angle
fixtures when I added the first crossbraces.
I carefully checked the fuselage alignment
as construction proceeded. Then I took the
structure off the board.
As I sighted along the fuselage to
confirm the beautiful, straight structure,
arrrggh! The wing-mount area was twisted
1/64 inch. That is just enough to put an
unwanted twist in the wing. How could
that happen? I don’t know, but at least I
figured out an easy way to fix it.
I use a MonoKote heat gun to take
warps out of wings, so I figured that there
was a chance it might work to adjust the
fuselage. Sure enough, it worked like a
charm!
Keep the fuselage moving over the heat
to avoid damage. Twist the structure as
needed to correct the misalignment. This
won’t turn a “pig’s ear into a silk purse”;
however, if the misalignment is minor, this
is an effective way to get the fuselage
framework straight.
I use Titebond to frame fuselages. That
may explain why the heat technique
works. I have not tried it with
cyanoacrylate.
Octavian Aldea built a beautiful Pfalz
from DPC Models’ laser-cut kit. It spans
18 inches and uses two 14-inch loops of
1/8-inch FAI Tan rubber. Octavian found
that the supplied loop of 3/16-inch rubber
left the airplane a bit underpowered.
The Pfalz weighs 35 grams without
rubber and uses a 6-inch Peck-Polymers
propeller. At that weight, it might benefit
AMA Academy of Model
Aeronautics
ARF Almost Ready to Fly
BEC Battery Eliminator Circuit
CAD computer-aided design
cc cubic centimeter
CD contest director or
compact disc
CG center of gravity
CL Control Line
cm centimeter
cu. in. cubic inch
DT dethermalizer
EPP (foam) expanded polypropylene
ESC Electronic Speed Control
FAI Fédération Aéronautique
Internationale
FCC Federal Communications
Commission
FF Free Flight
GHz gigahertz
Kv rpm/volt
kV killivolt (1,000 volts)
LCD Liquid Crystal Display
LE leading edge
LED light-emitting diode
Li-Poly Lithium Polymer
mA milliamperes
MA Model Aviation
mAh milliampere-hours
MHz megahertz
mm millimeter
Nats AMA Nationals
Ni-Cd Nickel Cadmium
NiMH Nickel Metal Hydride
RC Radio Control
rpm revolutions per minute
RTF Ready to Fly
SASE self-addressed, stamped
envelope
SIG Special Interest Group
TE trailing edge
Model Aviation’s
Frequently Used
Abbreviations /Acronyms
from two loops of 3/16-inch rubber.
Octavian covered the model with white
Esaki tissue. The markings are also tissue,
including the red heart and black arrow.
The Pfalz was finished with two coats of
nitrate dope before the markings were
applied. A final coat of clear nitrate dope
was applied to protect and bond the
markings.
The only problem Octavian
encountered during trimming was a degree
of lateral instability, indicated by the
airplane’s tendency to recover slowly
from a lateral wind gust.
At Wawayanda, New Jersey, this fall,
Octavian had the privilege of chatting
with a few great modelers, including
Vance Gilbert. He is extremely
experienced with and accomplished at
flying biplanes.
After watching the Pfalz fly, Vance
advised Octavian to increase the dihedral
on the upper wing from 0, as prescribed in
the kit, to roughly 1 inch. He also suggested
increasing the lower wing dihedral from 0
to 3/4 inch. Thanks to Vance, the lateralinstability
issue was solved.
Octavian made the preceding
modifications in the motel room at
Wawayanda before the second day of
competition. Ronny Gosselin supervised
and encouraged him, making sure that
Octavian finished the modification before
the second competition day. The best
flight so far is 21 seconds, but the model
is showing promise.
You can find DPC laser-cut kits for
several World War I airplanes on the Web
site. See the “Sources” list for contact
information. Several DPC kits, including
the Pfalz, are no longer listed on the DPC
Web site, because they are being updated
with new CAD plans and lighter
structures.
The updated kits will be released as
they become available. However, if you
want one of the older kits now, you can
get one. In addition, two nice Albatros
pseudo Dime Scale kits are currently
available. E-mail DPC Models for a list
and pricing.
In an accompanying photo, Bob
Schlosberg’s Herr Super Cub on floats
shows off its classic lines. Bob made some
modifications to the kit, even adding a
paddle on the inside of the right float. He
also slightly modified the rudder’s shape
to match the picture he has of the fullscale
aircraft.
Many hobby shops carry the Herr kits.
If you can’t find one there, check out Penn
Valley Hobby Center.
I have always liked the Fairchild 22’s
lines but have been hesitant to build one.
Parasol-wing configurations are known to
have less lateral stability than high-wing
cabin models. Bob Schlosberg decided to
build one despite that knowledge.
He started with Paul Lindberg
Fairchild 22 plans for a 16-inch-span
01sig5.QXD 11/24/08 1:12 PM Page 132
model. Bob enlarged the plans to produce a
26-inch wingspan, and he could not be
more pleased with the results. He reports
that the model is an excellent flier, even
with the scale dihedral.
Bob Mattes has an engine-rework
service for FF and CL power plants. He
has done a lot of work making Nelsonplug-
compatible heads for nostalgia-era
engines.
Bob recently developed a replacement
glow-head adapter for the Cox .020 Pee
Wee and Tee Dee engines. It costs
approximately the same as one would
pay for two of the increasingly rare Cox
.020 plugs on eBay.
Because of the tolerances involved,
Bob advises letting him make a custom
fit to your engine for best performance.
You can contact him via E-mail. See the
“Sources” list for the address.
Replacement Glow Bee plugs that
work with Bob’s adapter are roughly $4
each. They are available from Larry
Driskill through Kitting It Together. See
the “Sources” list for contact
information.
Diels Engineering, which sells great
Scale FF rubber-powered kits, has a new
Web site. See the “Sources” listing for
contact information.
Paul and Ralph Bradley’s Model
Airplane Page is one of my favorite Web
sites. While there last fall, I found that
several models had been added since my
previous visit. There are free downloads
for many neat World War II No-Cals, as
well as printing patterns that allow you
to re-create your own Jigtime and
Goldberg sheet-balsa flying models.
Don’t miss the tips and references
section. There are also micro-size and
electric-powered RC models for those
who enjoy that aspect of our hobby.
Visiting this site is a must. MA
Sources:
Texas Timers
(423) 282-6423
www.texastimers.com
NFFS Plans Service
(678) 242-8655
www.freeflight.org/store/plans/plans.htm
Campbell’s Custom Kits
(765) 389-1749
www.campbellscustomkits.com
Keith Sterner (Klass Wings, LLC)
4019 Nicholas St.
Easton PA 18045
[email protected]
DPC Models
1003 Sunset Tr.
Kingston Springs TN 37082
http://dpcmodels.homestead.com
Penn Valley Hobby Center
(215) 855-1268
www.pennvalleyhobbycenter.com
Mattes Engine Service
[email protected]
Kitting It Together
www.kittingittogether.com
Diels Engineering
Box 263
Amherst OH 44001
http://dielsengineering.samsbiz.com
Paul and Ralph Bradley’s Model Airplane
Page
www.parmodels.com
Edition: Model Aviation - 2009/01
Page Numbers: 129,130,132,135
Also included in this column:
• Contra-rotating propeller
unit
• Twisted fuselage frame fix
• Octavian’s Pfalz
• Herr Cub on floats
• Bob Mattes head for Cox
.020.
• Diels Engineering’s new Web
site
• Paul Bradley’s Model Airplane
Web site
[[email protected]]
Free Flight Sport Gene Smith
Gas model one design for 2009 Nats
Bob Stalick, former NFFS president, with his 1/2A Spacer: the 2009
Nats NFFS one-design event model. Stalick photo.
Keith Sterner’s beautiful and efficient contrarotating propeller
units are for sale by Klass Wings, LLC. Hallman photo.
Above: John Houck’s A2D
Skyshark, Dallas Cornelius’s
Martin Baker MB-5, and
Tom Hallman’s winning
Koolhoven use the Sterner
unit. Hallman photo.
Left: The Germans had
some beautiful paint schemes
for their airplanes, as
documented for Octavian
Aldea’s Pfalz. Hallman photo.
THE GAS MODEL for the NFFS
[National Free Flight Society] One Design
event at the 2009 Nats will be Sal Taibi’s
1/2A Spacer. Bill Vanderbeek will give
every participant a nice certificate with a
three-view of the model that John
Anderson drew.
As you can see in the photo, Bob
Stalick will be ready with his Spacer. The
beautiful site in the background is a grass
seed field 15 miles south of Albany,
Oregon.
Bob’s Spacer is equipped with a Wen-
Mac engine and a Tatone pinch-off timer.
An alternative to the Tatone is the Texas
January 2009 129
01sig5.QXD 11/24/08 12:48 PM Page 129
MICRO I from Texas Timers.
Bob feels that the best engine choice is
probably the Cox reed valve. He thinks the
Cox Medallion’s additional power would
make the Spacer more difficult to trim.
He suggests that anyone who is planning
to use a Medallion or similar engine use a
small (1/8 x 1/8 inch) top spar placed roughly
one-third of the way behind the wing LE.
The event rules allow that type of
modification, and it will give the wing more
stiffness and strength.
Bob originally trimmed the Spacer to fly
right under power and left in the glide.
More recent trimming procedures have the
model flying to the right for both power and
glide.
The current trim setup has 2° of
downthrust and 2° of left thrust. The rightwing
main panel is washed in 1/16-3/32 inch.
A bit of left rudder tab may be needed. Tilt
the stabilizer with the right side high for a
right turn in the glide. That should give you
a starting point for trimming.
Plans for the 1/2A Spacer are available
from the NFFS Plans Service. Plans and
short kits are available from Campbell’s
Custom Kits. It’s not too soon to start your
model. Nostalgia-legal .049 or .051 engines
are required.
Contra-rotating Propeller Unit: Keith
Sterner developed a new contra-rotating
propeller system that proved to be
extremely successful at last year’s FAC
[Flying Aces Club] Nationals. He had been
thinking about these little “CRPD” units for
a long time.
An E-mail that Tom Hallman sent out to
many of his friends early last year stirred
Keith into action. He saw the project as a
challenge.
Keith produced a rough working
prototype using a small plastic tube from a
glitter container, front and back plates of
1/16 birch plywood, and aluminum-tubingshaft
bushings. The gears were platedbrass
slot-car pinions.
That prototype was successful, so
Keith, Tom, and John Houck got together
in Keith’s workshop to share ideas about
the possibilities of the design, and the
project was born.
Keith refined the design and built the
second prototype, which he presented to
Tom and John. They agreed that the unit
was on the right track. Keith built the third
version, which Tom installed in his
Koolhoven and flew to a win at the FAC
Nats in Geneseo, New York, this past July.
John received the first large unit that
incorporated all that Keith had learned
while fabricating the small units. He
installed it in his A2D Skyshark and
finished in second place at Geneseo.
The small drive measures .750 inch
long, .720 inch wide, and .458 inch high,
and it uses a .032-inch-diameter-musicwire
propeller shaft. The large drive
measures 0.781 inch long, 1.438 inches
wide, and 0.917 inch high, and it uses a
.062-inch-diameter-music-wire propeller
shaft.
Customers can swap out the main
music-wire shaft for an equal-size shaft—
.032 or .062—they prefer that has the
hook shape they prefer. The units are
supplied with the standard diamond hook
shape.
132 MODEL AVIATION
Each unit includes documentation that
covers preparation, installation, and
maintenance. Installation covers the
preferred mounting, securing the main
shaft to the drive shaft, and altering the
main (music wire) and secondary (brass)
shafts to accommodate any length other
than the standard as supplied, which may
be required for a particular model. A
documentation sheet supplied with each
unit contains an actual-size four-view
drawing of it and the full-scale mounting
pattern.
The small gear-drive unit weighs 3
grams, and the large weighs 7 grams. The
small unit was designed to handle models
spanning as much as 20 inches, and the
large unit is for models spanning as much
as 30 inches.
The small units are in full production
and are priced at $40 each plus shipping
and handling. The large units are priced at
$50 each plus shipping and handling.
Contact Keith Sterner at Klass Wings; see
the “Sources” list for the addresses.
Twisted Fuselages: This may never have
happened to you, but it seems to happen to
me often when I build box fuselages for
my rubber-powered Scale models.
Let’s say I know I made the fuselage
sides identical. I pinned them to a flat
board and secured them with right-angle
fixtures when I added the first crossbraces.
I carefully checked the fuselage alignment
as construction proceeded. Then I took the
structure off the board.
As I sighted along the fuselage to
confirm the beautiful, straight structure,
arrrggh! The wing-mount area was twisted
1/64 inch. That is just enough to put an
unwanted twist in the wing. How could
that happen? I don’t know, but at least I
figured out an easy way to fix it.
I use a MonoKote heat gun to take
warps out of wings, so I figured that there
was a chance it might work to adjust the
fuselage. Sure enough, it worked like a
charm!
Keep the fuselage moving over the heat
to avoid damage. Twist the structure as
needed to correct the misalignment. This
won’t turn a “pig’s ear into a silk purse”;
however, if the misalignment is minor, this
is an effective way to get the fuselage
framework straight.
I use Titebond to frame fuselages. That
may explain why the heat technique
works. I have not tried it with
cyanoacrylate.
Octavian Aldea built a beautiful Pfalz
from DPC Models’ laser-cut kit. It spans
18 inches and uses two 14-inch loops of
1/8-inch FAI Tan rubber. Octavian found
that the supplied loop of 3/16-inch rubber
left the airplane a bit underpowered.
The Pfalz weighs 35 grams without
rubber and uses a 6-inch Peck-Polymers
propeller. At that weight, it might benefit
AMA Academy of Model
Aeronautics
ARF Almost Ready to Fly
BEC Battery Eliminator Circuit
CAD computer-aided design
cc cubic centimeter
CD contest director or
compact disc
CG center of gravity
CL Control Line
cm centimeter
cu. in. cubic inch
DT dethermalizer
EPP (foam) expanded polypropylene
ESC Electronic Speed Control
FAI Fédération Aéronautique
Internationale
FCC Federal Communications
Commission
FF Free Flight
GHz gigahertz
Kv rpm/volt
kV killivolt (1,000 volts)
LCD Liquid Crystal Display
LE leading edge
LED light-emitting diode
Li-Poly Lithium Polymer
mA milliamperes
MA Model Aviation
mAh milliampere-hours
MHz megahertz
mm millimeter
Nats AMA Nationals
Ni-Cd Nickel Cadmium
NiMH Nickel Metal Hydride
RC Radio Control
rpm revolutions per minute
RTF Ready to Fly
SASE self-addressed, stamped
envelope
SIG Special Interest Group
TE trailing edge
Model Aviation’s
Frequently Used
Abbreviations /Acronyms
from two loops of 3/16-inch rubber.
Octavian covered the model with white
Esaki tissue. The markings are also tissue,
including the red heart and black arrow.
The Pfalz was finished with two coats of
nitrate dope before the markings were
applied. A final coat of clear nitrate dope
was applied to protect and bond the
markings.
The only problem Octavian
encountered during trimming was a degree
of lateral instability, indicated by the
airplane’s tendency to recover slowly
from a lateral wind gust.
At Wawayanda, New Jersey, this fall,
Octavian had the privilege of chatting
with a few great modelers, including
Vance Gilbert. He is extremely
experienced with and accomplished at
flying biplanes.
After watching the Pfalz fly, Vance
advised Octavian to increase the dihedral
on the upper wing from 0, as prescribed in
the kit, to roughly 1 inch. He also suggested
increasing the lower wing dihedral from 0
to 3/4 inch. Thanks to Vance, the lateralinstability
issue was solved.
Octavian made the preceding
modifications in the motel room at
Wawayanda before the second day of
competition. Ronny Gosselin supervised
and encouraged him, making sure that
Octavian finished the modification before
the second competition day. The best
flight so far is 21 seconds, but the model
is showing promise.
You can find DPC laser-cut kits for
several World War I airplanes on the Web
site. See the “Sources” list for contact
information. Several DPC kits, including
the Pfalz, are no longer listed on the DPC
Web site, because they are being updated
with new CAD plans and lighter
structures.
The updated kits will be released as
they become available. However, if you
want one of the older kits now, you can
get one. In addition, two nice Albatros
pseudo Dime Scale kits are currently
available. E-mail DPC Models for a list
and pricing.
In an accompanying photo, Bob
Schlosberg’s Herr Super Cub on floats
shows off its classic lines. Bob made some
modifications to the kit, even adding a
paddle on the inside of the right float. He
also slightly modified the rudder’s shape
to match the picture he has of the fullscale
aircraft.
Many hobby shops carry the Herr kits.
If you can’t find one there, check out Penn
Valley Hobby Center.
I have always liked the Fairchild 22’s
lines but have been hesitant to build one.
Parasol-wing configurations are known to
have less lateral stability than high-wing
cabin models. Bob Schlosberg decided to
build one despite that knowledge.
He started with Paul Lindberg
Fairchild 22 plans for a 16-inch-span
01sig5.QXD 11/24/08 1:12 PM Page 132
model. Bob enlarged the plans to produce a
26-inch wingspan, and he could not be
more pleased with the results. He reports
that the model is an excellent flier, even
with the scale dihedral.
Bob Mattes has an engine-rework
service for FF and CL power plants. He
has done a lot of work making Nelsonplug-
compatible heads for nostalgia-era
engines.
Bob recently developed a replacement
glow-head adapter for the Cox .020 Pee
Wee and Tee Dee engines. It costs
approximately the same as one would
pay for two of the increasingly rare Cox
.020 plugs on eBay.
Because of the tolerances involved,
Bob advises letting him make a custom
fit to your engine for best performance.
You can contact him via E-mail. See the
“Sources” list for the address.
Replacement Glow Bee plugs that
work with Bob’s adapter are roughly $4
each. They are available from Larry
Driskill through Kitting It Together. See
the “Sources” list for contact
information.
Diels Engineering, which sells great
Scale FF rubber-powered kits, has a new
Web site. See the “Sources” listing for
contact information.
Paul and Ralph Bradley’s Model
Airplane Page is one of my favorite Web
sites. While there last fall, I found that
several models had been added since my
previous visit. There are free downloads
for many neat World War II No-Cals, as
well as printing patterns that allow you
to re-create your own Jigtime and
Goldberg sheet-balsa flying models.
Don’t miss the tips and references
section. There are also micro-size and
electric-powered RC models for those
who enjoy that aspect of our hobby.
Visiting this site is a must. MA
Sources:
Texas Timers
(423) 282-6423
www.texastimers.com
NFFS Plans Service
(678) 242-8655
www.freeflight.org/store/plans/plans.htm
Campbell’s Custom Kits
(765) 389-1749
www.campbellscustomkits.com
Keith Sterner (Klass Wings, LLC)
4019 Nicholas St.
Easton PA 18045
[email protected]
DPC Models
1003 Sunset Tr.
Kingston Springs TN 37082
http://dpcmodels.homestead.com
Penn Valley Hobby Center
(215) 855-1268
www.pennvalleyhobbycenter.com
Mattes Engine Service
[email protected]
Kitting It Together
www.kittingittogether.com
Diels Engineering
Box 263
Amherst OH 44001
http://dielsengineering.samsbiz.com
Paul and Ralph Bradley’s Model Airplane
Page
www.parmodels.com
Edition: Model Aviation - 2009/01
Page Numbers: 129,130,132,135
Also included in this column:
• Contra-rotating propeller
unit
• Twisted fuselage frame fix
• Octavian’s Pfalz
• Herr Cub on floats
• Bob Mattes head for Cox
.020.
• Diels Engineering’s new Web
site
• Paul Bradley’s Model Airplane
Web site
[[email protected]]
Free Flight Sport Gene Smith
Gas model one design for 2009 Nats
Bob Stalick, former NFFS president, with his 1/2A Spacer: the 2009
Nats NFFS one-design event model. Stalick photo.
Keith Sterner’s beautiful and efficient contrarotating propeller
units are for sale by Klass Wings, LLC. Hallman photo.
Above: John Houck’s A2D
Skyshark, Dallas Cornelius’s
Martin Baker MB-5, and
Tom Hallman’s winning
Koolhoven use the Sterner
unit. Hallman photo.
Left: The Germans had
some beautiful paint schemes
for their airplanes, as
documented for Octavian
Aldea’s Pfalz. Hallman photo.
THE GAS MODEL for the NFFS
[National Free Flight Society] One Design
event at the 2009 Nats will be Sal Taibi’s
1/2A Spacer. Bill Vanderbeek will give
every participant a nice certificate with a
three-view of the model that John
Anderson drew.
As you can see in the photo, Bob
Stalick will be ready with his Spacer. The
beautiful site in the background is a grass
seed field 15 miles south of Albany,
Oregon.
Bob’s Spacer is equipped with a Wen-
Mac engine and a Tatone pinch-off timer.
An alternative to the Tatone is the Texas
January 2009 129
01sig5.QXD 11/24/08 12:48 PM Page 129
MICRO I from Texas Timers.
Bob feels that the best engine choice is
probably the Cox reed valve. He thinks the
Cox Medallion’s additional power would
make the Spacer more difficult to trim.
He suggests that anyone who is planning
to use a Medallion or similar engine use a
small (1/8 x 1/8 inch) top spar placed roughly
one-third of the way behind the wing LE.
The event rules allow that type of
modification, and it will give the wing more
stiffness and strength.
Bob originally trimmed the Spacer to fly
right under power and left in the glide.
More recent trimming procedures have the
model flying to the right for both power and
glide.
The current trim setup has 2° of
downthrust and 2° of left thrust. The rightwing
main panel is washed in 1/16-3/32 inch.
A bit of left rudder tab may be needed. Tilt
the stabilizer with the right side high for a
right turn in the glide. That should give you
a starting point for trimming.
Plans for the 1/2A Spacer are available
from the NFFS Plans Service. Plans and
short kits are available from Campbell’s
Custom Kits. It’s not too soon to start your
model. Nostalgia-legal .049 or .051 engines
are required.
Contra-rotating Propeller Unit: Keith
Sterner developed a new contra-rotating
propeller system that proved to be
extremely successful at last year’s FAC
[Flying Aces Club] Nationals. He had been
thinking about these little “CRPD” units for
a long time.
An E-mail that Tom Hallman sent out to
many of his friends early last year stirred
Keith into action. He saw the project as a
challenge.
Keith produced a rough working
prototype using a small plastic tube from a
glitter container, front and back plates of
1/16 birch plywood, and aluminum-tubingshaft
bushings. The gears were platedbrass
slot-car pinions.
That prototype was successful, so
Keith, Tom, and John Houck got together
in Keith’s workshop to share ideas about
the possibilities of the design, and the
project was born.
Keith refined the design and built the
second prototype, which he presented to
Tom and John. They agreed that the unit
was on the right track. Keith built the third
version, which Tom installed in his
Koolhoven and flew to a win at the FAC
Nats in Geneseo, New York, this past July.
John received the first large unit that
incorporated all that Keith had learned
while fabricating the small units. He
installed it in his A2D Skyshark and
finished in second place at Geneseo.
The small drive measures .750 inch
long, .720 inch wide, and .458 inch high,
and it uses a .032-inch-diameter-musicwire
propeller shaft. The large drive
measures 0.781 inch long, 1.438 inches
wide, and 0.917 inch high, and it uses a
.062-inch-diameter-music-wire propeller
shaft.
Customers can swap out the main
music-wire shaft for an equal-size shaft—
.032 or .062—they prefer that has the
hook shape they prefer. The units are
supplied with the standard diamond hook
shape.
132 MODEL AVIATION
Each unit includes documentation that
covers preparation, installation, and
maintenance. Installation covers the
preferred mounting, securing the main
shaft to the drive shaft, and altering the
main (music wire) and secondary (brass)
shafts to accommodate any length other
than the standard as supplied, which may
be required for a particular model. A
documentation sheet supplied with each
unit contains an actual-size four-view
drawing of it and the full-scale mounting
pattern.
The small gear-drive unit weighs 3
grams, and the large weighs 7 grams. The
small unit was designed to handle models
spanning as much as 20 inches, and the
large unit is for models spanning as much
as 30 inches.
The small units are in full production
and are priced at $40 each plus shipping
and handling. The large units are priced at
$50 each plus shipping and handling.
Contact Keith Sterner at Klass Wings; see
the “Sources” list for the addresses.
Twisted Fuselages: This may never have
happened to you, but it seems to happen to
me often when I build box fuselages for
my rubber-powered Scale models.
Let’s say I know I made the fuselage
sides identical. I pinned them to a flat
board and secured them with right-angle
fixtures when I added the first crossbraces.
I carefully checked the fuselage alignment
as construction proceeded. Then I took the
structure off the board.
As I sighted along the fuselage to
confirm the beautiful, straight structure,
arrrggh! The wing-mount area was twisted
1/64 inch. That is just enough to put an
unwanted twist in the wing. How could
that happen? I don’t know, but at least I
figured out an easy way to fix it.
I use a MonoKote heat gun to take
warps out of wings, so I figured that there
was a chance it might work to adjust the
fuselage. Sure enough, it worked like a
charm!
Keep the fuselage moving over the heat
to avoid damage. Twist the structure as
needed to correct the misalignment. This
won’t turn a “pig’s ear into a silk purse”;
however, if the misalignment is minor, this
is an effective way to get the fuselage
framework straight.
I use Titebond to frame fuselages. That
may explain why the heat technique
works. I have not tried it with
cyanoacrylate.
Octavian Aldea built a beautiful Pfalz
from DPC Models’ laser-cut kit. It spans
18 inches and uses two 14-inch loops of
1/8-inch FAI Tan rubber. Octavian found
that the supplied loop of 3/16-inch rubber
left the airplane a bit underpowered.
The Pfalz weighs 35 grams without
rubber and uses a 6-inch Peck-Polymers
propeller. At that weight, it might benefit
AMA Academy of Model
Aeronautics
ARF Almost Ready to Fly
BEC Battery Eliminator Circuit
CAD computer-aided design
cc cubic centimeter
CD contest director or
compact disc
CG center of gravity
CL Control Line
cm centimeter
cu. in. cubic inch
DT dethermalizer
EPP (foam) expanded polypropylene
ESC Electronic Speed Control
FAI Fédération Aéronautique
Internationale
FCC Federal Communications
Commission
FF Free Flight
GHz gigahertz
Kv rpm/volt
kV killivolt (1,000 volts)
LCD Liquid Crystal Display
LE leading edge
LED light-emitting diode
Li-Poly Lithium Polymer
mA milliamperes
MA Model Aviation
mAh milliampere-hours
MHz megahertz
mm millimeter
Nats AMA Nationals
Ni-Cd Nickel Cadmium
NiMH Nickel Metal Hydride
RC Radio Control
rpm revolutions per minute
RTF Ready to Fly
SASE self-addressed, stamped
envelope
SIG Special Interest Group
TE trailing edge
Model Aviation’s
Frequently Used
Abbreviations /Acronyms
from two loops of 3/16-inch rubber.
Octavian covered the model with white
Esaki tissue. The markings are also tissue,
including the red heart and black arrow.
The Pfalz was finished with two coats of
nitrate dope before the markings were
applied. A final coat of clear nitrate dope
was applied to protect and bond the
markings.
The only problem Octavian
encountered during trimming was a degree
of lateral instability, indicated by the
airplane’s tendency to recover slowly
from a lateral wind gust.
At Wawayanda, New Jersey, this fall,
Octavian had the privilege of chatting
with a few great modelers, including
Vance Gilbert. He is extremely
experienced with and accomplished at
flying biplanes.
After watching the Pfalz fly, Vance
advised Octavian to increase the dihedral
on the upper wing from 0, as prescribed in
the kit, to roughly 1 inch. He also suggested
increasing the lower wing dihedral from 0
to 3/4 inch. Thanks to Vance, the lateralinstability
issue was solved.
Octavian made the preceding
modifications in the motel room at
Wawayanda before the second day of
competition. Ronny Gosselin supervised
and encouraged him, making sure that
Octavian finished the modification before
the second competition day. The best
flight so far is 21 seconds, but the model
is showing promise.
You can find DPC laser-cut kits for
several World War I airplanes on the Web
site. See the “Sources” list for contact
information. Several DPC kits, including
the Pfalz, are no longer listed on the DPC
Web site, because they are being updated
with new CAD plans and lighter
structures.
The updated kits will be released as
they become available. However, if you
want one of the older kits now, you can
get one. In addition, two nice Albatros
pseudo Dime Scale kits are currently
available. E-mail DPC Models for a list
and pricing.
In an accompanying photo, Bob
Schlosberg’s Herr Super Cub on floats
shows off its classic lines. Bob made some
modifications to the kit, even adding a
paddle on the inside of the right float. He
also slightly modified the rudder’s shape
to match the picture he has of the fullscale
aircraft.
Many hobby shops carry the Herr kits.
If you can’t find one there, check out Penn
Valley Hobby Center.
I have always liked the Fairchild 22’s
lines but have been hesitant to build one.
Parasol-wing configurations are known to
have less lateral stability than high-wing
cabin models. Bob Schlosberg decided to
build one despite that knowledge.
He started with Paul Lindberg
Fairchild 22 plans for a 16-inch-span
01sig5.QXD 11/24/08 1:12 PM Page 132
model. Bob enlarged the plans to produce a
26-inch wingspan, and he could not be
more pleased with the results. He reports
that the model is an excellent flier, even
with the scale dihedral.
Bob Mattes has an engine-rework
service for FF and CL power plants. He
has done a lot of work making Nelsonplug-
compatible heads for nostalgia-era
engines.
Bob recently developed a replacement
glow-head adapter for the Cox .020 Pee
Wee and Tee Dee engines. It costs
approximately the same as one would
pay for two of the increasingly rare Cox
.020 plugs on eBay.
Because of the tolerances involved,
Bob advises letting him make a custom
fit to your engine for best performance.
You can contact him via E-mail. See the
“Sources” list for the address.
Replacement Glow Bee plugs that
work with Bob’s adapter are roughly $4
each. They are available from Larry
Driskill through Kitting It Together. See
the “Sources” list for contact
information.
Diels Engineering, which sells great
Scale FF rubber-powered kits, has a new
Web site. See the “Sources” listing for
contact information.
Paul and Ralph Bradley’s Model
Airplane Page is one of my favorite Web
sites. While there last fall, I found that
several models had been added since my
previous visit. There are free downloads
for many neat World War II No-Cals, as
well as printing patterns that allow you
to re-create your own Jigtime and
Goldberg sheet-balsa flying models.
Don’t miss the tips and references
section. There are also micro-size and
electric-powered RC models for those
who enjoy that aspect of our hobby.
Visiting this site is a must. MA
Sources:
Texas Timers
(423) 282-6423
www.texastimers.com
NFFS Plans Service
(678) 242-8655
www.freeflight.org/store/plans/plans.htm
Campbell’s Custom Kits
(765) 389-1749
www.campbellscustomkits.com
Keith Sterner (Klass Wings, LLC)
4019 Nicholas St.
Easton PA 18045
[email protected]
DPC Models
1003 Sunset Tr.
Kingston Springs TN 37082
http://dpcmodels.homestead.com
Penn Valley Hobby Center
(215) 855-1268
www.pennvalleyhobbycenter.com
Mattes Engine Service
[email protected]
Kitting It Together
www.kittingittogether.com
Diels Engineering
Box 263
Amherst OH 44001
http://dielsengineering.samsbiz.com
Paul and Ralph Bradley’s Model Airplane
Page
www.parmodels.com