Construction shot showing the two lower halves of the fuselage with the 1⁄8- inch square balsa strip stringers (above left) and the 1⁄16-inch sheet upper pylon cabin blanks. Also shown is the 1⁄8-inch plywood firewall assembly with push cable for engine throttle and rough location for servo installation. Pylon/cabin flat sheet component (above right) with spruce wing mounting member being glued into place. Left and right fuselage halves (below left) shown with the
cabin/pylon assembly being final located and glued into place. Placing will depend on what you come up with for a motor and its requirements. The plan shows placing used for a Norvel .061 with a remote 2-ounce tank. Rough pre- positioning of components and radio equipment (below right) while it is still an easy task while the other side is still off. Location shown are suggested, but exact final installation for your fuselage will depend on your equipment.
sponse when properly rigged and I usually use 15% nitro glow fuel and also add some extra castor oil to the mix for longer life. You don’t need a throttle though and can just use a simple Cox Babe Bee .049 and let it run until the fuel runs out the way ½A Texaco planes are flown. Actually, almost all ½A planes used to be flown this way. If that seems like a lot of trouble to you, you are not alone. Many folks who have flown ½A over the years have had to come to grips with the idiosyncrasies of these little engines and lived to tell the tale. So if you can find an example of one of these engines locally, even without a throttle, this may be your best bet as a physical examination is possible and the seller should even be able to run it for you.
This is not usually the case with the sec- ond option. You can get one by scanning e- bay or one of the other online selling servic- es, but its sort of like buying a pig in a poke. You may get a good one from an honorable seller but there is always that “buyer be ware” attached to this course.
Another good source is to try to find one of these engines and some spare parts at the local model airplane club auction. This has the problem of when one might happen in your area and may not be the most timely
FLYING MODELS
way to acquire one of these engines. Finally, the Cox engines can often be found in some garage sales, estate auctions or flea markets for a very reasonable price, but again, the condition of the engine will vary widely. At this time it might be a good idea to pro- vide three main hints for good luck with these little powerplants if you have never used one before. The first hint is that every- thing needs to kept scrupulously clean. Es- pecially the fuel, fuel handling equipment and of course the engine.
The second most important item is a good glow plug battery, clip for attaching to the plug and of course the plug itself. If there is a good strong glow you are almost sure of a clean start. Finally, always run the fuel out of the engine until dry and then put some af- ter run oil in the engine to keep it from foul- ing up with goo (congealed lubricants). Fol- low these three steps with these small glow engines or any glow engine of any size for that matter and you will be well on your way to success.
By now you are probably beginning to see why the electric propulsion systems have, for the most part, replaced the ½A glow en- gines in this end of our hobby for beginners. Not only is the installation usually lighter and simpler, but there are fewer things to go
wrong and spoil your flying fun. There are fewer batteries to worry about charging and no worry about fuel contamination and dirt in the engine is not as big an issue. You don’t have to stick your finger in the prop arc to get the engine started or use an electric starter to avoid injury. You will nev- er have to clean the goo off an electrically powered plane or apply after run oil to the motor. There will also certainly be no com- plaints of noise from the neighbors of the fly- ing site.
There are several other things that you will have to get used to with a glow or “gas” type propulsion system of this type besides the noise. One of the first is that after start- ing the engine it must be transported from the pitting area to the flight line and run- way with a running engine. This must be done with care as that prop can do great in- jury if you get caught in it. The electric type of model does not need the prop turning un- til the actual moment of takeoff. If you get the model to the runway with- out it coughing or quitting it is also custom- ary to “clear” the engine and check the nee- dle valve setting by holding the nose high and running at full throttle for 10–15 sec- onds and checking the movements of all the controls before placing the model on the run-
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