Frequently Asked Questions - 2009/02 | Model Aviation Library

Author: Bob Aberle

Edition: Model Aviation - 2009/02
Page Numbers: 97,98,100

Frequently Asked Questions - 2009/02

Please write in with your questions; that is the only way we can keep this column format going. When referring to already published Q-and-As (for follow-ups), provide the number as a reference.

References to addresses and Web sites are placed in a group, separate from the text, at the end of the column under "Sources."

Q385: Where to get Enya model engine parts

Q385: "I own several Enya glow engines and am now in need of a few replacement parts. I went back to the original distributor, MRC in Edison, NJ, and found that they no longer carry the Enya line nor do they have any parts inventory. Can you direct me to someone who now sells these Enya engine parts?"

A385: I've used Enya glow engines almost exclusively since the early 1970s. I have several of these fine engines stored carefully in jars of kerosene.

After reading this e-mail, I went into the usual Web-site search-engine routine. It took a while, but I am glad to report that I received a response from Ken Enya in Japan. The company (Enya Metal Products of Saitama) is alive and well, and he is still making engines and parts.

Ken supplied me with the names and addresses of six Enya engine/parts distributors in the U.S. Space doesn't permit me to list them all here, but the first two on the list were BJ's Model Engine Service in Falls, Connecticut, and Aero Products in Dacula, Georgia. Please drop an e-mail to Ken Enya to get the names of the remaining four distributors. His address is in the "Sources" section.

Q386: Scotch tape for reinforcing foam wings

Q386: "I have used a package strapping tape for years to reinforce certain model aircraft wing structures. This was especially helpful with foam wings. The tape is a Scotch brand product and readily available. Recently one of my club members showed me a different kind of tape, also a Scotch product that might even do a better reinforcing job. Can you identify this tape?"

A386: You are referring to Scotch Extreme Application Packaging Tape, catalog number 8959. It comes in rolls that are 1.9 inches wide and 21 yards long and sells for roughly $9 apiece. I found this product at my local Home Depot.

Strapping tape normally has fibers that run in only one direction. This Extreme variety differs in that there are two sets of fibers running opposite to one another; Scotch calls this a "bi-directional filament."

I was introduced to this tape while reviewing the new Multiplex Blizzard high-performance electric sailplane. Because of the aircraft's anticipated speed, additional wing reinforcement using this tape was recommended.

The instructions specify the tape be applied at a 45° angle (not lengthwise) down the wing span. There will be variations in installation depending on the model and application. Although it is almost 2 inches wide, the tape can easily be cut into strips to fit any size of aircraft.

Q387: Positive arming switch for electric systems

Q387: "I know that most modern electric motor controllers (ESC) have built-in protection against accidental motor starts. You can't arm a motor unless the RC transmitter throttle stick is seen by the ESC software to be in the idle position. Years ago we used to see all kinds of arming switches that permitted a positive kill (disconnect) of the electric power system until we were ready to fly.

I have some large, high-powered systems and if nothing else would like a very positive arming switch to supplement the ESC feature. There must be someone who makes such a switch."

A387: Arming switches are thought of less often now because of modern microprocessor ESCs and their built-in protection. But a positive arming switch is still worthwhile. Without a switch, you may be drawing power somewhere in your system the minute the battery is connected.

The best way to employ an arming feature is to use a shorting plug in one of the two battery wires. Pulling the plug (which breaks the circuit) instantly disconnects all power going to your ESC and motor. If you are using a BEC, it will kill your radio system as well.

Maxx Products International (MPi) offers a variety of arming switches. They sell for approximately $10 and are available with both Deans Ultra and Anderson Powerpole connectors. You insert the harness into one of the two battery wires. A plug is inserted into this harness and the circuit is completed; your motor is armed and ready. The minute this plug is pulled, all power is off and you have the peace of mind of knowing your motor won't start accidentally.

MPi also offers related harnesses that allow you to connect Li-Poly battery packs in parallel to increase capacity or in series to increase voltage. It's worth a look at their Web site.

Q388: Stronger landing gear for GWS Slow Stick

Q388: "I'm flying a GWS Slow Stick and having trouble with the landing gear wire always bending on almost any kind of landing. Is there some kind of alternative available that offers a little more strength?"

A388: At the NEAT Fair in upstate New York, the Millennium R/C booth had a landing-gear system designed for the company's Slow Stick X and the GWS Slow Stick. Millennium R/C's Jim Karpy explained that the new X-Gear is made from carbon fiber and an ABS/nylon blend.

The gear is available in several colors and costs $14.95. It is adaptable to several other park flyers, such as the E-flite Mini Edge and Mini Ultra Stick, using a supplied adjustable mount.

Q389: Sources for cockpit interior detail

Q389: "I've seen a lot of references to detailed scale information, but was wondering if there is any info regarding the interior of the aircraft, namely the cockpit? I've noted at scale events that cockpit detail counts in the scoring. How do I get inside the aircraft?"

A389: There are many sources for that kind of information. I recently visited the Code One Magazine Web site, which is an airpower publication with a load of full-scale aircraft data.

On the site I found the "Special Cockpit Editor." When you open this page you will see photos of 32 aircraft; clicking an image opens a picture of the cockpit. I clicked on a PBY Catalina flying boat as an example.

This feature shows a few aircraft cockpits, but the site has so much information it is worth the time to dig in and scroll around.

Follow-up to Q371 (October 2008 MA)

I received a reader's e-mail indicating that in the diagram for the Castle Creations CC-BEC, I didn't mention that the red servo cable wire going to your RC receiver's throttle port is disconnected when using a brushless motor but must be connected when using a brushed motor.

I didn't think the type of motor mattered, so I contacted Castle Creations. The answer the company gave me was surprising. The distinction is with the ESC — not the motor.

If your ESC is of the opto-isolator variety, it has no BEC. In that case, the red wire is left connected. For all other applications, regardless of the type of motor employed, the red wire must be disconnected, as I wrote in the column.

All of Castle Creations' Phoenix HV ESCs have opto-isolators, so the red wire must stay connected on those units. If this still isn't clear, contact Castle Creations; they will be glad to advise you.

If you continue to have a problem, the Castle Creations customer-support department is ready and willing to help.