Radio Control Soaring 2010/07

102 MODEL AVIATION
WELCOME TO
the clinic. They let
me have coffee
again, so please
keep that in mind as
you read on.
Sailplanes for Sale:
My financial
advisor has
informed me that
hoarded sailplanes
cannot be counted
as part of my net
worth or as part of my retirement plan. I knew I married her for a
reason.
Many of us love new toys or even adopting those that have been
resting in someone else’s hangar. The market for these gems is
active this time of year. A great place to sell or buy sailplanes is on
the Internet Soaring forums, such as the sailplanes-for-sale page on
RCGroups.
Post a picture and a price. The trickiest part of the whole process
is properly packing the models for shipment.
I’ve found that a little lumber goes a long way. Get some cheap
1-inch wood at the home-improvement shop and cut it to fit the
internal length of the box, to help prevent crushing.
Okay, So They Crunched It
Anyway: John Buxton of
Bakersfield, California, gave
me a repair tip that worked
well. He is an extreme DS
(dynamic soaring) Sloper,
but I hope you Thermal
Duration fliers will not
hold it against us.
John suggested
supporting crunched areas
of the fuselage or wing from
the inside with a spongy
material, such as foam soaked in
Right: The crystal-clear nose cone on the Elf shows
the one-cell Shred RC Smart Lipo power system. It
includes a circuit board that boosts the voltage up to 5
and doubles as the charger.
[[email protected]]
Radio Control Soaring Lee Estingoy
Also included in this column:
• An easy repair technique
• Toledo Show wrap-up
• Upcoming events
Sailplanes for sale
Above: Barry Kennedy holds the 1-meter
mosquito-class Elf Hand-Launched Glider. It
looks like a great time.
Primitive “X-ray” of the Mini Ellipse wing
repair shows how epoxy-soaked foam can
be pushed inside the wing to reinforce the
crinkled wing skin.
Foam reinforcement neatly fills the access hole. All that’s left is to put a bit of matching
sign vinyl over the patch and go fly!
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July 2010 103
Etienne Dorig, of ICARE, shows off the mind-blowing 1-meterspan
SZD 55 Sloper.
epoxy. The foam can remarkably easily be maneuvered to the
wound site and will provide incredible support for that wrinkled part
of the wing or cracked tailboom.
This repair method is lighter than it sounds. I tried it on a Mini
Ellipse that went down in a fight with the shipper. The wing was
crinkled roughly two-thirds of the way out to the tip. The spar was
clearly bent there as well.
My arthroscopic skills and toolbox aren’t up to John’s
standards, so I used a 3/8-inch Forstner bit to drill/cut a nice hole
in the D-box section immediately in front of the spar at the site of
the crinkle. On the bottom I used carbon to reinforce the spar
itself, but a good deal of the wing’s strength depends on the
stability of the wing skin.
I decided to try the epoxy-and-foam technique. I cut some gray
packing foam to a size that was slightly larger than the length and
thickness of the repair site.
Then I mixed a small amount of good thin epoxy (laminating or
similar). I worked the epoxy into the foam by mashing the foam into
the epoxy on a piece of waxed paper.
You might be cringing at the weight of this right now. Wrong!
Make sure to thoroughly wring out the epoxy from the foam.
Twist it, press it, or roll it like a toothpaste tube—whatever you
want. You will be amazed by how the epoxy’s weight can be
reduced.
Push the foam into the soft area. That 3/8-inch hole worked great
for this. A bit of the foam wanted to poke out of the hole, so I
covered it with plastic tape.
Let this cure for a while and then take off the tape. I was amazed
to see that the hole was neatly filled with hardened material that was
flush with the lower skin of the wing. The wing skin was nicely
supported, and the weight penalty was minimal.
This will also work well in tailbooms. But please keep in mind
any pushrods that might need to share space with your foam.
Hall Pass for Toledo: The staff here at the clinic gave me a
weekend pass in April, and I made the annual pilgrimage to Toledo,
Ohio, and the Weak Signals’ show, where Kennedy Composites,
Skip Miller Models, ICARE, and the League of Silent Flight (LSF)
showed their wares.
Barry of Kennedy Composites led me to believe that I could take
one of the beautiful Elf micro Hand-Launched Gliders home at the
end of the show. They feature beautiful carbon layups for the wing
LE and a novel crystal-clear pod that snuggles the servos, receiver,
and battery pack. I was crushed when he told me on Sunday evening
that he didn’t want to share the Elf!
Barry had some interesting receiver/servo batteries. They
consisted of one Li-Poly cell and circuitry that boosted voltage from
the battery to the required volts. This circuit doubles as a charger, so
charging from a 12-volt DC source is a snap. These little guys are
light!
Skip of Skip Miller Models had the latest in sailplane exotica, as
usual, such as the Orca 4-meter tip extensions, the Satori F3J model,
and an updated Topaz.
It was good to visit with Cody Remington, a 2010 US F3J team
pilot, and see some of the colorful, cool F3J team shirts. Yes, this is
the second time I’ve mentioned these shirts in this column; please
consider supporting the team!
It can’t be inexpensive to go to Geneva, Switzerland, in August.
It is the location of the closest airport to the event in Taveaux,
France.
On the topic of Switzerland, Etienne Dorig, proprietor of
ICARE, quietly passed me a DVD containing some incredible
sailplane footage. It seems as though Etienne meets buddies in
Switzerland for a Slope Soaring vacation. I can’t decide which is
more breathtaking: the models or the scenery. He also had the cute
mini SZD on display.
Jim Deck and Mike Stump held down the LSF table. I joined
them for a bit of a rabbinical discussion about the rules for the
electric-powered Soaring class that they are working on.
It looks like there are several options for an altitude-triggered
motor kill switch coming to market soon. This will guarantee that
the models start at the same height and aims to kill the electric
fliers’ predisposition to motoring to great heights and keeping the
wings level until the sailplane needs to land to make the target
time—or so they say.
They don’t know the innovation we electric-power pilots can
display! I’m totally onboard with the concept of having the “winch
in the nose of the plane,” and Jim and Mike were preaching to the
choir when they explained how much simpler the Soaring
experience is with the option of self-launching sailplanes.
Summer Events: If you were unable to attend the JR Aero Tow in
June or are looking for a great event that is closer to you, consider
the Mickey Sullivan Memorial Fly in Wichita, Kansas. It is
scheduled for August 20-22 at Clearview Field.
I doubt that you will meet a nicer group of RC fliers than Ken
Stitt and his gang. You can obtain information about this event on
the Web site. MA
Sources:
RCGroups
www.rcgroups.com
Kennedy Composites
(972) 602-3144
www.kennedycomposites.com
Skip Miller Models
(303) 442-6454
www.skipmillermodels.com
ICARE
(450) 449-9094
www.icare-rc.com
League of Silent Flight
www.silentflight.org
JR Aero Tow 2010
www.horizonhobby.com/Arti
cles/Article.aspx?ArticleID=1
906
Clearview Field
www.clearviewfield.com
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