March 2001 135
I’ll sTarT this column with a warning.
At the last meeting for my club, one flier
announced that he had become sensitized to
cyanoacrylate (CyA) glues and had
considerable pain, and the other warned about
the paints in use on our models.
Since this is the middle of the building
season for most in our hobby, the warning is
timely. As much fun as building is for most
of us, the chemicals and tools common to
our building methods subject us to some
noxious stuff.
We see a great deal of information on
propeller safety, but it’s important to be aware
of several other areas.
I’ve seen a number of people develop
dermatitis from CyA or super glues, and I
know several fliers who have developed it
from epoxy resins. These are particularly
painful types of dermatitis.
You should wear impervious gloves—
latex or polyvinyl chloride (PVC)—to protect
yourself from these chemicals.
The more you use these adhesives, the
more likely you are to become sensitized to
them. Your system can only tolerate so much
buildup of the chemicals, then it revolts—
much to your displeasure and discomfort.
Many modelers are using two-part epoxy
paints or two-part polyurethane paints, and
most of the two-part polyurethane paints use
cyanide as part of the catalyst.
Use care, adequate ventilation, and proper
respiratory protection when painting and
building your models.
What’s new? I received a letter from Nick
Arpino, who informed me he was retiring
from making his DARP magnesium Speed
pans. Nick has turned the title of “Master Pan
Man” over to Mr. Barry Tippett, who will
supply the entire line of Speed pans.
I purchased a couple of RB Concept’s .21
engines. I believe NovaRossi in Italy makes
these for Rody Roem in France. The main
advantage to Rody’s product line for our
purposes is that they are lighter than the
NovaRossi line. I purchased the C3, which is
a five-port engine with single exhaust.
I also got a Roem modified C4 “Worlds”
engine, with seven intake ports and three
exhaust ports. I will report on this engine in
the future; it has several unique features,
including a dished piston and an
asymmetrical head shape.
These engines are available in the US
from Sigma Trading.
Cyclon .40 front-intake engines have
finally been produced, and have arrived in the
US. The craftsmanship is superb, and the
performance has been excellent.
Contest news: I received a very nice letter
from Court Hughes of the Rocky Mountain
Aeromodelers, with results of the club’s
annual Speed meet.
The event was held Labor Day weekend,
and it was great. Weather was in the high 80s
and low 90s, and there was just enough wind
to let participants know they were at a contest.
Saturday’s activities were mainly contestants
fine-tuning their equipment for Colorado’s
rarified air and getting some practice.
Sunday was for official flights; the day
was perfect for flying, with the exception of a
couple high wind gusts coming through.
All Speed events were combined and
flown record-ratio. There was also a special
1⁄2A Mouse event, which was limited to
Junior contestants.
If you want your local happenings known,
send them to me and I will fit them in
whenever I can.
Engine Corner: I can’t tell you how many
people have asked me to give the goods on
engine rework. I’ll start with the most basic
part of it: engine-cleaning.
I’ll discuss proper break-in in the next
issue, then I will go into the “good stuff.”
None of what follows originated with
me. I have gleaned 90%+ of what is here
from Alexander Kalmykov, Sergei Kostin,
and Rob Metkemeyer—all of whom I have
discussed engine preparation with at
considerable length, and are acknowledged
for their engine prowess.
Sometimes it seems that assembling an
engine without dirt is the most difficult part of
preparing one, and it stands for 50% of its
quality. So whatever you do with the engine, or
parts of it, clean, clean, clean before reassembly.
I used to be able to assemble an engine in
20-30 minutes. After Sergei Kostin was
finished with me, I have trouble doing it in
less than three hours.
Cleaning means first disassembling and
degreasing all the parts. I use brake cleaner or
a similar thinner or solvent. Other products
can be used, as long as the oil and grease
(especially castor oil) is completely taken off
without rusting the steel parts.
There are two important points
regarding disassembly: some engines
CONTROL LINE SPEED
Scott Newkirk, 4840 N. Glendale, Bel Aire KS 67220
Dave Rolley Jr. of Bennett, Colorado holds his Cyclon-powered
1⁄2A Proto model. Photo provided by Court Hughes.
Marty Schoenheiter (Salt Lake City, Utah) with his Nelsonpowered
Formula 40 model. Photo provided by Court Hughes.
136 M ODEL AVIATION
require heat to remove the cylinder and
most engines require heat to remove and
reinstall the bearings.
I usually start at 300°, and go to 350° if the
lower setting is inadequate. Most oil that has
not been removed attempts to make itself a
permanent part of the crankcase at 350°, and
you start to anneal the crankcase at 425°.
Clean all the parts separately. Dirt tends
to spread rather than wash away. If you try
to clean a complete ball race in an ultrasonic
cleaner, all the dirt that is in safe places will
move to harmful places. The result is that
the bearing will be useless until you take it
apart and clean each piece.
Yes, I take my bearings apart and clean
them ball by ball. The care is the same for
the piston/connecting rod/piston wrist pin
assembly; the components come apart and
get a thorough cleaning.
The crankcase and the head need their
own precleaning bath; they get very dirty on
the outside, and this dirt should not reach the
inside of the engine.
Cleaning should take place in at least two,
and preferably three, stages. The last stage
should be done in new, super-clean fluid. In
the second stage, I scrub the parts with a
toothbrush and liquid dishwashing detergent. I
learned this from Sasha Guievsky.
The ports in the cylinder especially need
this type of attention; it is difficult to see the dirt
inside the ports, and the toothbrush does an
excellent job of getting into the tight corners.
Remember the holes in the wrist pin and the
wrist-pin holes in the piston; the dirt that comes
out here will harm the piston skirt directly!
Using an ultrasonic cleaner is preferred for
the last stage. The risk of spreading the smallest
particles to places you don’t want them is
present. Following the ultrasonic cleaning with a
compressed-air blast will drive away the small
particles and dry the parts.
I use the liquid dish soap and water in my
ultrasonic cleaner. Some liquid detergents are
too strong, and will discolor your aluminum if
they get warm. Some people use acetone,
solvent, kerosene, and other flammable
materials, but I prefer not to.
You should assemble the parts with
clean hands in a clean room (usually not
your workshop). Take the parts you are
prepared to assemble directly from the
clean bath, and grease them lightly with
nonoxidizing oil (steel parts rust when
degreased.); I prefer to use kerosene.
Use castor oil for the big and small ends of
the rod, and for the wrist pin to the piston. I use
kerosene for assembling the piston to the
cylinder and the crankshaft to case and the
bearings. I like to use a small amount of antiseize
compound in the threaded holes in aluminum.
The cleaning and oiling process is very
important for preventing wear and tear on
your expensive and carefully set-up engine.
Once it’s clean, bag your engine and set
it aside. I don’t usually put my engines in
my airplanes until I’m ready to fly them.
If I do leave an engine in an airplane
after flying, I flush it out with brake cleaner
and generously apply kerosene. Then I plug
the intake and exhaust, and put a bag around
the whole front end of the model.
If you’re not having fun, you’re not
doing it right! MA
sources:
RB Concepts engines:
Sigma Trading
Box 510589
New Berlin WI 53151
Fax: (262) 789-8108
www.sigmatrading.com
www.rbproducts.com
DARP pans:
Barry Tippett
31052 Mason St.
Livonia MI 48154-4336
(734) 266-7250
Cyclon engines:
Alexander Kalmykov
pr. Dzerjinskogo 2-67
Russia, 630112 Novosibirsk
Preferably via E-mail: [email protected]
North American Speed Society (NASS):
Box 82294
North Burnaby, British Columbia
Canada, V5C 5P7
Results of the Rocky Mountain Aeromodelers’ (Colorado) annual Speed meet, which
was held Labor Day weekend 2000.
