Up and Around
George M. Aldrich
12822 Tarrytown, San Antonio, TX 78233
Trailing Edge
During the past year there has not been a single week when I did not hear from someone interested in—or getting involved with—some sort of Old-Timer modeling. Regardless of the reasons so many have been drawn back to this trailing-edge-of-technology modeling, a pervasive attitude is felt by many of us: winning, just for the sake of winning, is not the main attraction. For the majority—even many who once competed at an almost frantic level—the demands and obligations of our present lifestyle prevent winning from being the most important part of our interest.
In this high-tech world of Schnuerle-ported engines, exotic electronics, and RTF (ready-to-fly) or ARF (almost-ready-to-fly) models, why would such a large contingent choose to go back in history to build and fly designs that are 40 or more years old? With our AMA Nationals sporting 90-plus events, competition or winning a trophy has to be of secondary importance.
Whether you are reliving your early years, building a design you always admired, or experiencing an activity you only read about, recreation has to be the prime motivation. I would suggest this be taken to mean both to re-create and to refresh.
It has been said that Old-Timers are a dying breed. Because some of us do show various amounts of gray in our hair, such a conclusion might be drawn. However, since many younger people do get involved, let me hasten to amend this: Old-Timer building and flying is far from dead.
One of the early tenets of Old-Timer modeling was not to advance the state of the art. This has provided many newcomers with the opportunity to rediscover old building techniques, as well as to operate engines on spark ignition.
Engines: Spark vs. Diesel
Now to an aspect of flying Old-Timers that I have never seen addressed in quite this way. In racing events, as soon as you say race, winning becomes closely related to dollars spent. Old-Timer events attempt to duplicate modeling the way it was. This means using the basic type of engine and fuel prevalent during the era being recreated.
In free flight, the engine run allowed is 25 seconds ROG (rise-off-ground), 20 seconds HL (hand-launch)—just as in late pre–World War II times. During this period, over 90% of modelers used a fuel consisting basically of 70-weight oil and gasoline. Even in the early postwar years the spark engine and gas ’n oil were used by the great majority.
While we in the U.S. concentrated on developing spark-ignition engines, the English leaned more to compression-ignition, or diesel, engines. Greatly hampered by the war and direct attacks like the Battle of Britain, industry in the U.K. remained behind us for some time. Certainly, the diesel engine was not seriously considered for free flight before 1950 in this country. In fact, only one engine from this era has any effect on OTFF as it is flown today—the Elfin 2.49cc (.15 cu. in.) diesel. Because of the weight saved by eliminating the ignition system, coupled with the high output of the Elfin, it is very difficult to compete on an equitable basis using a spark-ignition-powered model.
Having had a love affair with diesels for more than 25 years, I own reproductions of the Elfin built in three different countries. I also have two A-class, SAM-legal models: a Comet Mercury (288 sq. in.) powered with a very good Morrill .19 ignition engine and a Megow Ranger (347 sq. in.) with a Dunham or Argo Elfin up front. Both models fly very well and are a real pleasure. In early morning buoyant air, the Elfin’s ability to swing a larger prop and the resulting flight-time gain is easily apparent.
Obviously, winning is not a prerequisite for us to continue to build and fly OTFF powered by true spark-ignition engines. Perhaps enough of us care about retaining the event as truly flown that we will promote a spark-ignition-only event. Just the smell of old gas ’n oil fuel brings back fond memories of a well-spent youth and aided in no small way in making a lot of fine people today.
Nostalgia and Stunt Events
In Old-Time or Vintage stunt there are two basic events, with a third hanging in. These are commonly referred to as Nostalgia, Old-Time, and Old-Time Ignition stunt events. Although the stunt community is not afflicted to a great degree by the win-at-all-costs attitude, it does need a solid set of universal rules with a means of including unknown or unrecognized designs.
Only about 20% of the models flown during the 1947–1950 era are considered legal. The unrecognized designs include many that placed or won in national competition and a 1949 Netzeband design that was far ahead of its time. Fortunately, the engine is not a controversial problem in stunt. A wealth of fine engines are available that can be made to run properly, even if they don’t from the outset.
The main reason for the great outpouring from so many seems to be the attraction of returning to simpler times. Build them the way they were—balsa, silkspan, easy paint jobs. No high-tech needed here! A little carbon fiber to reinforce spars—or glassed nose sections—just makes a model more durable; otherwise no changes in design or construction are desirable.
Fuel Foaming and Anti-foam Solutions
A number of newsletters I receive have included comments about ways to eliminate fuel foaming. It seems someone discovered that a couple of squirts of one of the compounds sold to treat upholstery, tires, etc., would virtually prevent foam from forming in the fuel tank. Most such products contain a form of liquid silicone, which breaks down surface tension and thereby hampers the fuel’s ability to form bubbles. I have no way of knowing all the ingredients in these products, but they really aren’t very compatible with our fuel.
Another way to eliminate fuel foaming is to use a wetting agent. Basically, a wetting agent is meant to make water wetter. Such agents are used in diverse industries ranging from farming to photography. In farming, a wetting agent saves in the amount of insecticide needed to cover an acre because it wets the surfaces of the leaves better.
Photographers use a product that is far easier to obtain in small quantities. Almost every photography supply shop carries a product called photo-flow solution, used for treating prints. Because it is available in concentrated form, only one or two drops are needed for an entire gallon of fuel. When I was in the fuel business some years ago, two ounces were added to every 156 gallons as an antifoam agent.
Timers and Microswitches
A number of readers have written to say that Fourmost Products produces a one-way check valve to stop fuel from backflowing into the engine via the pressure line. Others have written to ask about the availability of engine shutoff timers for ignition systems. To my knowledge no one is producing such an item at this time.
Most modelers mount a microswitch directly on the timer case. After notching out the face plate, my routine is to tack the microswitch in place with a tiny drop of CyA (cyanoacrylate) glue. After I am certain everything is set up properly, a line of slow (thick) CyA is applied and given a shot of kicker to set it up quickly. Many variations are possible; I got this one from Bruce Chandler more than 10 years ago.
After-run Oil and Synthetic Lubricants
For years many of us who used synthetic lubricants in our engines assumed there was no need to put after-run oil in the engine when we were through for the day. That is not the case. I still recommend after-run oil—whether you use synthetics or not. Once again, I use Rislone, but Marvel Mystery Oil is good too. Both are available from your local auto supply.
Trends in Engines and Porting
With so many different engines coming into my shop, I get a broad view of trends in porting arrangements currently in production. Some manufacturers, like SuperTiger, are producing both a ringed-piston/steel-liner version and a true ABC version in several sizes. Oddly, ABC versions all have relatively high or tuned-pipe/muffler timing.
For example, a G-45 ABC I checked had 155° exhaust timing, while the CL G-51 built in the same basic case had only 140°. This does not follow in all sizes, however, as the G-29 ABC, G-34 ABC (with ringed piston), and G-34 ringed/steel cylinder all checked out in the 155° exhaust timing range. With timing this high, these engines are obviously aimed at the tuned-pipe/muffler RC market.
However, if propped to let them really turn high revs, they could also make fine free flight engines. I plan to use a G-34 ABC with modified intake port timing as a test bed for a tuned-pipe/muffler setup in a profile Nobler. The idea is to find a simple, less expensive way to gain power while continuing to suppress noise that will cost us flying sites.
Also, a number of engines now on the market have nickel-plated cylinders. Commonly called ABC (Aluminum piston, Brass-Chromed cylinder), these latest editions are really ABN. This is not a criticism, but make no mistake—chrome is much harder than nickel. It is also much more difficult to plate chrome than nickel and thus more expensive. One important point: since nickel is softer, it would be wise to increase the castor oil content in the fuel for these ABN engines.
It is my understanding that Paul Walker won both our AMA Nationals and the World Stunt Championships using an O.S. .46 VF (ABN) engine that has two years and over 2,500 flights on it. A remarkable performance for all concerned.
The great resurgence of nostalgia stunt and free flight is starting to put a real drain on the engines that apply to this era. The only non-Schneider engines of .35 or above still in production come from Fox and Merco. We used to think nothing of running 60% nitro fuel in a K&B Greenhead, because a new part was as near as the local hobby shop. Today, even if parts can be found, we are well advised to use fuel with at least 25% castor oil and a maximum of 25% nitro.
I have also noticed various nostalgia free flights that sound like they are climbing at 100 mph when they really are doing only about 40 or less. Perhaps this is because we have become accustomed to running our K&B 3.25 Schneider at 24,000 rpm on an 8 x 4 prop, and put the same prop on a .19 Greenhead because it is the same size. In reality these engines are as different as oranges and roses. The port timing for most engines from this era says they are luggers—meant to develop maximum output at a much lower rpm range, and this means they can swing a larger prop. They will last longer if run in this manner, and in most cases get just as high or higher.
Deciphering which engines are allowed in the NFFS Nostalgia class competition has become a real chore in sizes larger than .049. It might simplify things quite a bit if the rule simply stated, "Any non-ball-bearing engine with a baffle on the piston if it was made after 1957 (cutoff date)." Perhaps some manufacturers would then go back to making good, dependable, less expensive non-Schneider engines for us.
Safety: Field Practices and Helicopters
A nice example of safety-minded behavior: at one field a pilot landed his plane on the runway and carried it back to the pits instead of taxiing it back. My hat goes off to Ken Robbins of the Helena Flying Tigers. How many of you can boast an identical concern for safety?
A little closer to home and more recently, my fledgling endeavors to fly helicopters led me to SAM field in DeSoto, Mississippi, for the annual Memphis Fall Helicopter Fun Fly. Obviously, I was curious to learn more about rotor heads and the safety practiced at such events.
Contest Director Mike Fortune set the tone during the pilots’ briefing by indicating that no one needed to take unnecessary chances that might result in an aircraft’s demise. Flight lines and different flying times for pilots in each class, frequency control, and five-foot safety fences for the spectators were the order of the day.
Doing your maintenance before arriving at the flying field with a helicopter is a must—the chopper’s rotor head will come apart if poorly maintained. The quality of what was presented for static and flying events was superb. I was very impressed by the professionalism, flying abilities, and well-maintained machines of Mike Fortune (X-Cell 60 Custom), Dana Swah (Kalt Baron Alpha 2), and Michael A. Cusanelli (modified Schulter 60 Scout). A first-class event with safety in the lead!
Props, Spinners, and a Safety Reminder
A concern passed on to me by Dave Elliott, a pattern flier with the Millington, Tennessee, Barnstormers Club: several fliers using carbon-fiber props have had them disintegrate in the air. Dave handed me the remains of several props for inspection. All displayed symptoms of an identical problem: each prop had been subjected to spinner-compression squeeze as a result of trying to fit a high-pitch prop into a shallow spinner opening. As a consequence, the spinner cut into the carbon fiber, thereby ruining its reliability. It was an accident waiting to happen.
The fix is to open up the slots in the spinner until they are large enough to ensure the spinner will not touch the prop once it has been secured to the spinner backplate. I’ve used a Dremel tool with a sanding drum to open the holes successfully on all my aluminum and plastic spinners. The final touch is to balance the spinner utilizing any one of several balancing systems available in hobby shops.
Remember: If your prop is damaged in any way, safety has been severely compromised and it is not worth the risk to try using it "one more time." A simple rule to follow is: when in doubt, throw it out.
Contact
For those of you who have written and sent SASEs, you know I answer my mail. I have a fax machine at (210) 656-2021. It will answer after six rings; hang up after five, and you won't be charged if I'm away.
Until next month, have a safe one and get those cards, letters, and pictures flowing.
Transcribed from original scans by AI. Minor OCR errors may remain.
