Also included in this column:
• Laser-cut Vortex kits are
now available
• Exponential discussion
• 2006 NMPRA Q40
Championship
• F3D US Team Trials
• Winter tips and hints
SANTA CLAUS
made a special
daytime delivery to
my house this year.
But he was driving a
big, brown truck
instead of a sleigh
pulled by eight
smelly reindeer.
And what did he
deliver? A new
Vortex Q-500
(Quickie 500) built
by one of his most
famous elves: Mr.
Chuck Bridge.
Chuck Bridge’s Vortex is more than an airplane; it’s a piece of art.
I tried to hang it over the mantle, but my wife said it clashed with our
window coverings and insisted that I return our family portrait back to
its original location. Chuck does an outstanding job, and the Vortex’s
success is unparalleled.
The Vortex wing is fully composite and painted in the mold. The
fuselage is built with traditional materials: balsa and plywood. The
fuselage is then fiberglassed and painted. As is the wing, the V-tail is
composite and painted in the mold.
Chuck custom-builds the servo trays and pushrods for your specific
equipment. His attention to detail is evident throughout, all the way
from the recessed servo-hatch cover to the polished aluminum landing
gear. The only thing left for the new owner to do is mount the engine
and install the electronics and the fuel tank.
The only downside to ordering a Vortex is the wait. Chuck can
build one in approximately three weeks, but with 20-30 names on the
waiting list it can take some time for Santa to make the delivery.
However, read on.
Vortex Laser-Cut Kits: Chuck has teamed up with Marcus Blanchard
to offer a laser-cut-fuselage version of the Vortex Q-500 at a
competitive price. The kit will consist of
Chuck’s composite Vortex wing and a balsaand-
plywood laser-cut fuselage and tail.
According to Marcus’s initial tests, the
Vortex should be a competitive racer. Pricing,
although subject to change, will start at $375
plus shipping and handling and will include
laser-cut fuselage and tail parts and a twocolor
composite Vortex wing.
Race numbers and additional colors will
cost extra. Rumor has it that the wait time will
be two to three months. Look for a more
detailed write-up in my next column.
Exponential or Not: I know many RC pilots
who choose not to use exponential (expo),
Novocain, stitches, or belts. I will address the
topic of expo at this time.
Following is Futaba’s explanation of
expo, as printed in its manuals.
“Exponential—Normally, servos respond
proportionally to control stick input from the
transmitter (e.g. if the stick is moved halfway,
the servo will move halfway). However, with
‘exponential,’ the servo can be made to move more or less than
initial stick movement (less servo movement is more common).
“Exponentials are commonly used to ‘soften,’ or decrease initial
servo travel for the ailerons, elevators and rudder. This way, initial
control stick inputs from the pilot result in small servo movement
for a smoother flying airplane. (Dual rates adjust the amount of
servo travel. Exponentials determine where most of the travel will
occur.)”
The manual does not address the fact that we are using the rotary
motion of a servo to deflect a linear-driven pushrod. This rotary
motion presents a problem, but thanks to Hipparchus, whom I’ve not
seen at a race in years, we have a solution.
Hipparchus, a Greek astronomer who lived between 190 and 120
B.C., is considered the father of trigonometry. Trigonometry,
specifically the sine function, illustrates our problem and allows us
to use expo to correct the problem.
Please reference Figure 1 and Table 1. Notice that initial
movements of the servo wheel away from neutral result in nearproportional
pushrod movements. However, servo-wheel
movements far from neutral do not.
Simply, the farther our servo moves from neutral, the less
proportional our pushrod movements are. In race terms, the more we
move the stick from neutral, the less effective our control becomes.
Without using expo, our model will be most sensitive around
neutral and least sensitive at the extremes. This is opposite from
what I want and probably what Hipparchus wanted. I would rather
have a “soft” feel around neutral.
Adding approximately 25% expo seems to return the feel to
something more proportional throughout the entire range of servo
movement. I have found that 40% expo gives me the feel I want for
my racers and seems to dampen my race-day jitters quite nicely.
If you have never considered expo values this high, try it; you
might like it (along with Novocain, stitches, and belts). Please note
that when using a Futaba transmitter the expo values need to be
negative. If you have comments or questions regarding
trigonometry, E-mail them to Hipparchus.
Chuck Bridge built Kurt’s new Vortex Q-500. A kit version, coming soon, will include one
of Chuck’s composite wings, a laser-cut fuselage, and tail parts for you to build.
NMPRA Quarter 40 (Q-40) Championship:
The Rogue Eagles Club located in Medford,
Oregon, hosted the 2006 NMPRA Q40
Championship race October 21-22. Mike
“Getterdone” Del Ponte was CD, and he
posted a big thanks to all the course workers
and participants on several of the Web
forums. According to him, the racing was
excellent and everyone had fun.
“Even the workers were excited and had a
great time—and are ready to do it again,” he
wrote.
Following are more comments from Mike.
“The weather could not have been better!
The food was great and the banquet was lots
of fun, thanks to our emcee, Bob Brogdon,
and David Doyle’s comedy act.
“Those of you who could not make it
missed out on some exciting racing. It was
like every heat was a flyoff. You should have
seen Gino and Grunk going at it until Grunk’s
radio quit. Whew!
“We had 24 entries and completed 10
rounds. We finished six rounds on Saturday
by 2:30 (with no reflies!) and finished the last
four rounds on Sunday. Everything was
wrapped up by 2 p.m. on Sunday.
“Thanks so much to the Washington State
support and the loan of some equipment. Our
wireless light system worked perfectly.
“We had a big surprise for the workers on
Sunday: Dub Jett donated an engine to be
given to one of the workers by drawing! Tom
DeAscentis was the lucky winner. Thank you,
Dub Jett!
“Thanks to Judi Del Ponte for announcing
and to Tom Strom Jr. for completing the
Matrix. It was good to see all of our buddies
again, and to see Lee Vonderhey come out of
semi-retirement and do so well. Once again,
thanks to all the racers and we look forward
to seeing you all next year.”
Following are the top 10 finishers.
1. Dub Jett: 1:04.17
2. Gino Del Ponte: 1:03.16
3. Gary Schmidt: 1:04.46
4. Mike Helsel: 1:02.43 (Fast Time)
5. Fred Burgdorf: 1:03.17
6. Lee VonDerHey: 1:05.67
7. Jim Allen: 1:04.36
8. Eric Ide: 1:04.18
9. Scott McAfee: 1:04.80
10. Jerry Small: 1:04.95
F3D US Team Trials: The San Fernando
Valley Radio Control Flyers hosted the F3D
US Team Trials August 3-6, 2006, at the club
field located in the Sepulveda Basin just
outside of Los Angeles, California. Barry
Leavengood served as CD.
The 2007 US F3D team will consist of
Fred Burgdorf, Randy Bridge, and Travis
Flynn. The F3D World Championships will
be held in our backyard, in Muncie, Indiana,
June 30-July 4.
Tips and Tricks: I have a few items for you
to consider during the winter break. Consider
adding a US quarter or two to your model’s
left wingtip if you find your airplane
consistently climbing during every turn
(especially at Pylon One).
Consider reducing the amount of down
travel to roughly half the amount of up travel.
This can be done via the dual rate function in
the more complex radios. You will have to do
this via the ATV (Adjustable Travel Volume)
menu in the older radios.
Also consider increasing the downelevator
expo to something greater than the
up-elevator expo setting. However, older
transmitters might not allow for separate up
and down settings.
Consider increasing your trim rates for
that first test flight. This will allow you to
quickly trim the airplane, although not
precisely. This would have saved me—I
mean “my friend”—a model a few years
back.
Set your trims back to something
smaller after the initial flight. For Futaba
transmitters I test-fly with the trims set at 4
and then move them back to 2 for the
remaining flights. I have raced with trim
settings reduced to the lowest possible
values, thinking it would help me fine-tune
even better. However, the smallest settings
required too many clicks of trim to see a
result.
Brake cleaner purchased from an
automotive parts store is a great cleanser for
engines, especially when you do a little fourwheeling
during landing. Use brake cleaner—
not carburetor cleaner! Carburetor cleaner is
too strong and can melt plastics; just ask my
aforementioned “friend.” And finally, afterrun
oil is great for those squeaky wheels.
The Jedburg Flyers of Charleston, South
Carolina (Tri-County Area), hosted an
AMA 424 (Sport Quickie)/428 (Quickie
500) race November 4-5. Rumors have it
that the Jedburg Flyers and CD Marcus
Blanchard put on a great contest and had a
mouthwatering Southern barbecue Saturday
evening.
Scott Causey and David Grubb, both new
to Pylon Racing, did exceptionally well and
even took home some trophies! Scott was
also the lucky winner of a shiny, new Nelson
Q-500 engine donated by Dave Shadel of
Performance Specialties (www.pspec.com).
Following are the top three in each class.
Sport Quickie
1. Neal Rehm
2. Scott Causey
3. David Grubb
Q-500
1. Gary Freeman Sr.
2. Randy Bridge
3. Gary Freeman Jr.
As always, if you have suggestions for future
columns, please send them my way.
Edition: Model Aviation - 2007/02
Page Numbers: 137,138
Edition: Model Aviation - 2007/02
Page Numbers: 137,138
Also included in this column:
• Laser-cut Vortex kits are
now available
• Exponential discussion
• 2006 NMPRA Q40
Championship
• F3D US Team Trials
• Winter tips and hints
SANTA CLAUS
made a special
daytime delivery to
my house this year.
But he was driving a
big, brown truck
instead of a sleigh
pulled by eight
smelly reindeer.
And what did he
deliver? A new
Vortex Q-500
(Quickie 500) built
by one of his most
famous elves: Mr.
Chuck Bridge.
Chuck Bridge’s Vortex is more than an airplane; it’s a piece of art.
I tried to hang it over the mantle, but my wife said it clashed with our
window coverings and insisted that I return our family portrait back to
its original location. Chuck does an outstanding job, and the Vortex’s
success is unparalleled.
The Vortex wing is fully composite and painted in the mold. The
fuselage is built with traditional materials: balsa and plywood. The
fuselage is then fiberglassed and painted. As is the wing, the V-tail is
composite and painted in the mold.
Chuck custom-builds the servo trays and pushrods for your specific
equipment. His attention to detail is evident throughout, all the way
from the recessed servo-hatch cover to the polished aluminum landing
gear. The only thing left for the new owner to do is mount the engine
and install the electronics and the fuel tank.
The only downside to ordering a Vortex is the wait. Chuck can
build one in approximately three weeks, but with 20-30 names on the
waiting list it can take some time for Santa to make the delivery.
However, read on.
Vortex Laser-Cut Kits: Chuck has teamed up with Marcus Blanchard
to offer a laser-cut-fuselage version of the Vortex Q-500 at a
competitive price. The kit will consist of
Chuck’s composite Vortex wing and a balsaand-
plywood laser-cut fuselage and tail.
According to Marcus’s initial tests, the
Vortex should be a competitive racer. Pricing,
although subject to change, will start at $375
plus shipping and handling and will include
laser-cut fuselage and tail parts and a twocolor
composite Vortex wing.
Race numbers and additional colors will
cost extra. Rumor has it that the wait time will
be two to three months. Look for a more
detailed write-up in my next column.
Exponential or Not: I know many RC pilots
who choose not to use exponential (expo),
Novocain, stitches, or belts. I will address the
topic of expo at this time.
Following is Futaba’s explanation of
expo, as printed in its manuals.
“Exponential—Normally, servos respond
proportionally to control stick input from the
transmitter (e.g. if the stick is moved halfway,
the servo will move halfway). However, with
‘exponential,’ the servo can be made to move more or less than
initial stick movement (less servo movement is more common).
“Exponentials are commonly used to ‘soften,’ or decrease initial
servo travel for the ailerons, elevators and rudder. This way, initial
control stick inputs from the pilot result in small servo movement
for a smoother flying airplane. (Dual rates adjust the amount of
servo travel. Exponentials determine where most of the travel will
occur.)”
The manual does not address the fact that we are using the rotary
motion of a servo to deflect a linear-driven pushrod. This rotary
motion presents a problem, but thanks to Hipparchus, whom I’ve not
seen at a race in years, we have a solution.
Hipparchus, a Greek astronomer who lived between 190 and 120
B.C., is considered the father of trigonometry. Trigonometry,
specifically the sine function, illustrates our problem and allows us
to use expo to correct the problem.
Please reference Figure 1 and Table 1. Notice that initial
movements of the servo wheel away from neutral result in nearproportional
pushrod movements. However, servo-wheel
movements far from neutral do not.
Simply, the farther our servo moves from neutral, the less
proportional our pushrod movements are. In race terms, the more we
move the stick from neutral, the less effective our control becomes.
Without using expo, our model will be most sensitive around
neutral and least sensitive at the extremes. This is opposite from
what I want and probably what Hipparchus wanted. I would rather
have a “soft” feel around neutral.
Adding approximately 25% expo seems to return the feel to
something more proportional throughout the entire range of servo
movement. I have found that 40% expo gives me the feel I want for
my racers and seems to dampen my race-day jitters quite nicely.
If you have never considered expo values this high, try it; you
might like it (along with Novocain, stitches, and belts). Please note
that when using a Futaba transmitter the expo values need to be
negative. If you have comments or questions regarding
trigonometry, E-mail them to Hipparchus.
Chuck Bridge built Kurt’s new Vortex Q-500. A kit version, coming soon, will include one
of Chuck’s composite wings, a laser-cut fuselage, and tail parts for you to build.
NMPRA Quarter 40 (Q-40) Championship:
The Rogue Eagles Club located in Medford,
Oregon, hosted the 2006 NMPRA Q40
Championship race October 21-22. Mike
“Getterdone” Del Ponte was CD, and he
posted a big thanks to all the course workers
and participants on several of the Web
forums. According to him, the racing was
excellent and everyone had fun.
“Even the workers were excited and had a
great time—and are ready to do it again,” he
wrote.
Following are more comments from Mike.
“The weather could not have been better!
The food was great and the banquet was lots
of fun, thanks to our emcee, Bob Brogdon,
and David Doyle’s comedy act.
“Those of you who could not make it
missed out on some exciting racing. It was
like every heat was a flyoff. You should have
seen Gino and Grunk going at it until Grunk’s
radio quit. Whew!
“We had 24 entries and completed 10
rounds. We finished six rounds on Saturday
by 2:30 (with no reflies!) and finished the last
four rounds on Sunday. Everything was
wrapped up by 2 p.m. on Sunday.
“Thanks so much to the Washington State
support and the loan of some equipment. Our
wireless light system worked perfectly.
“We had a big surprise for the workers on
Sunday: Dub Jett donated an engine to be
given to one of the workers by drawing! Tom
DeAscentis was the lucky winner. Thank you,
Dub Jett!
“Thanks to Judi Del Ponte for announcing
and to Tom Strom Jr. for completing the
Matrix. It was good to see all of our buddies
again, and to see Lee Vonderhey come out of
semi-retirement and do so well. Once again,
thanks to all the racers and we look forward
to seeing you all next year.”
Following are the top 10 finishers.
1. Dub Jett: 1:04.17
2. Gino Del Ponte: 1:03.16
3. Gary Schmidt: 1:04.46
4. Mike Helsel: 1:02.43 (Fast Time)
5. Fred Burgdorf: 1:03.17
6. Lee VonDerHey: 1:05.67
7. Jim Allen: 1:04.36
8. Eric Ide: 1:04.18
9. Scott McAfee: 1:04.80
10. Jerry Small: 1:04.95
F3D US Team Trials: The San Fernando
Valley Radio Control Flyers hosted the F3D
US Team Trials August 3-6, 2006, at the club
field located in the Sepulveda Basin just
outside of Los Angeles, California. Barry
Leavengood served as CD.
The 2007 US F3D team will consist of
Fred Burgdorf, Randy Bridge, and Travis
Flynn. The F3D World Championships will
be held in our backyard, in Muncie, Indiana,
June 30-July 4.
Tips and Tricks: I have a few items for you
to consider during the winter break. Consider
adding a US quarter or two to your model’s
left wingtip if you find your airplane
consistently climbing during every turn
(especially at Pylon One).
Consider reducing the amount of down
travel to roughly half the amount of up travel.
This can be done via the dual rate function in
the more complex radios. You will have to do
this via the ATV (Adjustable Travel Volume)
menu in the older radios.
Also consider increasing the downelevator
expo to something greater than the
up-elevator expo setting. However, older
transmitters might not allow for separate up
and down settings.
Consider increasing your trim rates for
that first test flight. This will allow you to
quickly trim the airplane, although not
precisely. This would have saved me—I
mean “my friend”—a model a few years
back.
Set your trims back to something
smaller after the initial flight. For Futaba
transmitters I test-fly with the trims set at 4
and then move them back to 2 for the
remaining flights. I have raced with trim
settings reduced to the lowest possible
values, thinking it would help me fine-tune
even better. However, the smallest settings
required too many clicks of trim to see a
result.
Brake cleaner purchased from an
automotive parts store is a great cleanser for
engines, especially when you do a little fourwheeling
during landing. Use brake cleaner—
not carburetor cleaner! Carburetor cleaner is
too strong and can melt plastics; just ask my
aforementioned “friend.” And finally, afterrun
oil is great for those squeaky wheels.
The Jedburg Flyers of Charleston, South
Carolina (Tri-County Area), hosted an
AMA 424 (Sport Quickie)/428 (Quickie
500) race November 4-5. Rumors have it
that the Jedburg Flyers and CD Marcus
Blanchard put on a great contest and had a
mouthwatering Southern barbecue Saturday
evening.
Scott Causey and David Grubb, both new
to Pylon Racing, did exceptionally well and
even took home some trophies! Scott was
also the lucky winner of a shiny, new Nelson
Q-500 engine donated by Dave Shadel of
Performance Specialties (www.pspec.com).
Following are the top three in each class.
Sport Quickie
1. Neal Rehm
2. Scott Causey
3. David Grubb
Q-500
1. Gary Freeman Sr.
2. Randy Bridge
3. Gary Freeman Jr.
As always, if you have suggestions for future
columns, please send them my way.