ThIS MonTh’S column will cover an “SSC
Champion,” USC reader reaction, hobby project
panel labels, an easy foam-repair technique,
small airplane pushrod adjustments, and a
quarter-century-old Electric model resurrected.
The often-mentioned Sport Speed Control
(SSC) construction article (9/99, 10/99 MA)
has brought a wide array of reader comments
and questions, but a new piece of
correspondence stands apart.
In the May 2000 issue, I wrote about a
reader who had built three SSCs at once—
quite a leap of faith. Since then, I met a reader
at a meet who told me he also built three
SSCs.
Now those stories have been topped; the
first reader I mentioned reported building six
additional SSCs, for a grand total of nine! I
have no choice but to pronounce him “Grand
SSC Champion”!
But there is more to this story. The “Champ”
had previously reported making an error
common to the first three assemblies: a missed wire. When this was
corrected, all three SSCs worked perfectly.
More recently, his goal was to build six new units perfectly the first
time. He came close—five worked immediately.
Although it was a disappointment, the sixth only had a mixed-up
resistor problem. This guy had made piles of all the parts at the start,
and somehow one wrong resistor got into one of the parts groups and
went undetected until checkout.
Nevertheless, this is a grand accomplishment. I can hardly wait to
see what this E-aeromodeler does next!
The Universal Slow Charger (USC) article (9/00 MA) has also
brought in quite a few reader comments, and some questions.
Perhaps the most impressive information was from two readers
who had built, and were using, the dual version—within three weeks of
reading the article!
That’s really moving, given that all the parts and supplies had to be
ordered/purchased, then assembled. Both readers independently
figured out that the article had some typos, and both worked through
them with quick inquiries to me.
(USC article errata were covered in the 10/00 and 11/00 MAs.)
One of these gentlemen is not an E-flier, and the other had never
built anything on pc holeboard before!
Most reader interest has been in the dual version of the USC. This
is interesting, because the dual is a larger, more-costly undertaking. I
guess this says that aeromodeling has a “whole lotta chargin’ to do”!
This is supported by another frequent reader comment, that many
who used the old ACE dual charger for many years really liked it, but
have contemporary charging needs beyond that discontinued product.
They were very happy to see the USC article.
Some readers inquired if the USC was available ready-built or as a
kit. Sorry, but no.
I’m really happy and gratified that so many readers have reacted
so positively to the Universal Slow Charger. I’m especially happy
that no one expressed upset or impatience with the few typos that
crept into that presentation. All patiently pursued those things, and
all has worked out fine, as far as I know.
As is always the case, if anyone has a comment or question about the
Bob Kopski, 25 West End Dr., Lansdale PA 19446
RADIO CONTROL ELECTRICS
Various homemade instruments with ink-jet printed paper panels, as described in text.
Labels can be made easily with a simple CAD program, and they look good.
Hole in Wingo’s foam fuselage pod was patched with cotton and
yellow glue. Cotton filled hole easily. Text has details.
Pushrod adjustment technique on Lite Stik uses wheel collars.
Much easier to adjust accurately than “Z bend.”
January 2001 121
USC (or about anything else), write and I’ll do
my best to answer all.
hobby Project Panel Labels: Labels such as those
in the USC and in other articles, such as the Pulse
Mini-Lab (6/98 MA) and the Servo Cycler (9/98
MA), add considerable appeal to homemade
instruments, and frequently bring reader inquiries.
Since so many have asked, here’s how I do it.
Generally at the outset of a project, I sketch a
rough panel layout—an initial arrangement of
switches, knobs, connectors, etc.
I follow that up with a more-serious,
dimensioned layout on my personal computer; my
software is TurboCAD by IMSI. I also use this
program for all drawing work, including pc board
assembly, schematic drawings, and modelconstruction
plans.
I can usually draw and print panel layouts
full-size. This is really convenient, because I normally print two
versions for each panel.
One is a “construction” version, wherein I show all drill
centers, etc. I attach it as a template to the panel (usually
aluminum), by smoothly rubbing an Elmer’s® Glue Stick on the
aluminum, positioning the paper pattern, then pressing it in place.
Center-punching the hole locations and drilling follow.
Soak the panel and paper in warm, soapy water. The Elmer’s®
dissolves easily. Rinsing, drying, then some hole deburring results in
an accurate panel.
Now for the second, or final, paper panel label. I generally run
it off on higher-quality paper, using the “best” print option on my
ink-jet printer. This version has the mechanical stuff (e.g., drill
centers) removed, and any appropriate lettering added. (All of this
can be done with the program’s “layer” feature.)
I cut a few hole locations with a fresh X-Acto™ #11 blade, and I
use these holes in the paper to line up with the drilled holes in the
panel, for overall accurate alignment.
I use the Elmer’s® Glue Stick again, and I make sure it’s really
smooth. I press the label in place and smooth with finger pressure,
using a temporary cloth over the paper.
When all this is finished, I use clear Con-Tact® paper as a cover,
to protect the printed label paper. It has worked very well throughout
the years.
Sometimes I make the paper label slightly undersize around the metal
panel perimeter, so that the clear cover extends roughly 1⁄16-inch past the
paper, onto the aluminum. All that remains is to cut out the remaining
label holes with the X-Acto™ at the drilled hole locations.
Visit turbocad.com, and download a free version to try. It is a fully
workable, but “smaller” version of the normal software product.
It works well enough that when I gave a friend a copy of all my
original SSC drawing files, he opened them and printed them on this
demo version. He subsequently purchased the software, which is
economical and quite powerful, and file-transfers with AutoCAD®.
ZAP III and EMPS MGK system, 1970 original-design six-meter Galloping Ghost
transmitter, “super-regen” receiver controls Adams pulse rudder, motor on/off.
The Wingo from Hobby Lobby is an
incredibly popular Almost Ready-to-Fly
(ARF) Electric model. I’ve seen many in
the last few years, and I have also flown
them for people.
The mostly-foam assembly
notwithstanding, this is a rather robust
airplane and is relatively hard to damage.
However, damage is possible, as one local
modeler learned; he landed a bit fast, into a
small stone on the ground. The stone punched
a hole in the bottom front of the fuselage pod,
and I offered to fix it for him.
As I set about the task, I realized it was not a
balsa repair; I was initially at a loss about how
to plug the sort-of-crumbly opening, which was
approximately one inch by two inches.
I soaked some cotton with Titebond
yellow glue (carpenter’s glue), which turned
into a messy job; I didn’t want too much
glue, but I did want it soaked all the way
through the cotton wad.
I stuffed this glob into the jagged foam
opening, worked it, and smoothed it, so it
filled the void and packed neatly, blending
into the rough perimeter as well. I worked it
until it “looked good.”
Drying took two full days, but it was
worth it. The cotton/glue combo turned into
one tough patch in the foam pod, and the
dried spot seemed every bit as durable as the
foam structure itself.
I put an overcoat of five-minute epoxy
on the bottom front of the pod, for added
durability; that area is the first to encounter
Mother Earth in the event of a nose-down
landing.
This remedy has worked well so far.
Except for the drying time, this was a
“quickie” repair that was easy to do with
readily available materials.
Next time, I’ll thin the yellow glue a bit
with water, then use a heat lamp to speed the
drying time. This should produce an even
better, quicker outcome.
Pushrods can be a challenge to adjust in
small airplanes, because adjustable clevises
are rarely used.
I’ve tried the “Z-bend” approach, but it is
not always easy to work with—especially
when you are trying to get a fine adjustment.
The photo of my Lite Stik shows an easy
solution to this problem.
I made the pushrods in two pieces, and
“coupled” them roughly in the middle with a
1⁄16-inch wheel collar. These rods are made
from steel wires that are thin enough to fit in
the collar bore and allow the rods to overlap
approximately 3⁄4-inch, as shown.
When the overlap is adjusted for correct
overall rod length, the collar set screw is
tightened to secure the joint.
Readjustment (if needed) is just as easy. If
heavier pushrods are used, the wheel collar
bore can be opened up slightly or a larger
collar can be used.
The MgK motor kit from EMPS, Inc.
(Box 134, Robesonia PA 19551; Web site:
www.empsinc.com) is an increasingly
popular small power system that works
very well.
The kit consists of a small motor, gears,
propeller shaft and bearing, and propeller.
This $13.95 (plus postage) system is used
with three to six cells.
I got one of these kits to try. After simple
assembly work and a run on the bench, I
needed something to put the motor in.
Inspiration struck, and I remembered an old
Electric model I had up in the attic.
I dug around, and I recovered my 26-
year-old ZAP III—all dirty and twisted and
“moused.”
The ZAP III has history; it was my first
Electric model that actually climbed!
Notes from 1974 indicate that the model
was powered by a Mattel™ toy motor/gears (no
longer available), and it used a (now-missing)
“super-regen” receiver with an Adams pulse
actuator on rudder and motor control!
I recovered the well-aged, very warped
Solarfilm-covered surfaces in MonoKote®. I
replaced wood where mice had munched, and
I located the old receiver assembly.
A few days of repair got everything up and
running. My own rules of thumb combined
with weight and power measurements showed
that I needed four Ni-Cds. This was a problem,
because the original installation was designed
for three Ni-Cd pencells.
After some circuit modifications and a
charge-up of my 1970 homebuilt six-meter
Galloping Ghost transmitter, it was “off to
the field!”
Since I didn’t have elevator, the on/off
motor control was a bit crude, and I really
didn’t know what was going to happen, I
used the ’ol “limited charge” technique; I put
roughly 20 seconds worth of motor run in the
new four-cell 500 mA pack, and launched.
The ZAP III had good forward speed, but
steady sink. I added positive incidence, and got
less sink. I added slightly more shim and some
recharge, and up it went, wiggling all the way!
Wow!What memories this rekindled!
In “those days,” one had to work hard,
with determination, to get an Electric model
to fly; nowhere near the way things are now.
But it was fun, and ZAP III is fun again.
I’ve been flying ZAP III regularly, and I
flew it at a meet. Some people are amazed at the
pulsing rudder, the pulse rate change to effect
motor on/off, and the more-than-10-minute
flights I’m getting with this 12-ounce, quartercentury-
old airplane, receiver, and transmitter.
The new EMPS MGK is doing a great job
in this old, but born-again attic find!
That’s just a story of fun I thought some
readers would like, because the hobby is,
after all, for fun.
So ends the first column of the new year.
I’m writing this during Labor Day
weekend, with anticipation of the Northeast
Electric Aircraft Technology (NEAT) meet
in a few weeks.
By the time you read this, you might have
witnessed ZAP III at NEAT, if I can find a
break in the six-meter flight activity for a few
minutes—a necessity, since it’s a “re-gen” (I
trust you all know what that means)!
Please enclose an SASE with any
correspondence for which you’d like a
reply. MA
