Author: Mark Fadely
Edition: Model Aviation - 2010/11
Page Numbers: 126,127,128
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Radio Control Helicopters

Mark Fadely [[email protected]]

Helicopters talk smack

Welcome to MA's helicopter pad. All things rotary land here. This month I present good advice from our friends Bert Kammerer and Bobby Watts. They produce an online helicopter resource called SmackTalk RC.

Bert and Bobby are wonderful pilots, and each has dedicated a great deal to the hobby. Now you can go to the Internet and get excellent tips and advice from proven experts.

I asked the two to share an excerpt of their work for this month’s helicopter column. Following are some helpful hints from Bert.

  • Are you experiencing tail issues?

If you suddenly encounter tail issues, such as an intermittent tail wag or a tail vibration, check your tailboom supports before you check the gyro or tail servo. Loose tailboom supports can cause nasty tail behavior.

Fasten your tailboom supports using green Loctite instead of blue, and make sure you tighten them well. On some helicopters, such as the Align T-Rex 700, make sure that the carbon tailboom support rod is properly glued to the end socket.

Sometimes the glue breaks free and the carbon rod separates from the plastic socket, causing tail issues. If this happens, remove the long setscrew that holds the carbon rod to the socket, separate the two, and use J.B. Weld to glue them together. Once the adhesive sets, your tailboom support should not come unglued again.

  • Find zero pitch on your blades.

Have you ever wondered if your blades are exactly zero pitch at half stick? You can use pitch gauges to determine this, but sometimes they are inaccurate—especially if your model’s flybar is not level. A neat trick is to power your transmitter and receiver, set the transmitter collective stick at half, and then fold the helicopter blades, allowing the blade tips to get extremely close to each other. (Be smooth and careful when folding the blades; this can put stress on your servos.) If the blade tips are aligned with each other at this point, you have achieved zero pitch.

If the tips are not aligned, move your transmitter stick up or down smoothly until they are. If the stick is below the halfway point, you have more positive than negative pitch. If your transmitter is above half-stick, you have more negative than positive. Unfold the blades, adjust your linkages, and fold again. Repeat the process until your blade tips align with each other when your transmitter is at half stick.

  • Have you had a servo wire disconnect in flight?

It’s no fun. Unless it is a servo other than throttle, you know your machine is going to crash. A good way around this is to use Goop adhesive. Use it to glue the servo connectors to your receiver or flybar unit, and they won’t come off. Goop can be easily removed, leaving practically no residue. You can buy it at any major hardware store.

  • Do you have trouble getting the tail belt through the boom?

I have seen people fight with tail belts when it is time to run them through the boom. The easiest way to do this is to wrap electrical tape around the end of the tail belt and then feed the belt into the boom; it will come out the other side with no effort.

  • Is the fuel foaming on your nitro-powered machine?

I see many pilots at the field flying nitro helicopters with fuel tanks that are constantly foaming. Some look like they have hurricanes inside them. This is extremely detrimental to the health and ease of tuning an engine.

The main reason fuel would foam on a nitro machine is high-frequency vibration. Unfortunately you can't see it with the naked eye. The most common cause of such vibration is a bent engine crankshaft. Many fliers go through hard crashes, rebuild their helicopters, and get back to flying with a bent crankshaft. Even though the power plant will run, it produces high-frequency vibration that will manifest itself in the fuel tank as foam.

If you see foam in your tank and you have experienced a hard crash, use a dial indicator to make sure your engine crankshaft is not bent. Anything less than two thousandths of an inch (.002") of runout is acceptable; anything more will require you to replace the crankshaft.

Another reason for tank foam could be lack of dampening on your fuel tank. On some helicopters, such as the T-Rex 700, the fuel tank can fit too tightly on the frames. Use a Dremel tool to remove material from the frames to loosen the tank fit. The tank should move a bit left to right if forced by hand; it shouldn't feel “glued” to the frames.

How did SmackTalk RC get started?

"I was approached by a production company a couple of years ago to work on producing an instructional DVD. At the time my schedule was too tight and I couldn't commit to it, so I had to pass on that opportunity.

"Last year, Bobby and I flirted with the idea of doing a DVD together. We both thought about renting an RV and traveling the country for a month or two visiting events, teaching people how to fly, and shooting footage for a DVD.

"Once again, after careful consideration we both came to the understanding that it wouldn't work because it would be too expensive to produce. We had to let the idea go.

"Finally, around November of the same year (2009) it occurred to us that we could have a 'Video Cast' released monthly over iTunes. Unfortunately we found out that iTunes would not be viable because they didn't offer a pay-per-view option, only a free option, and we needed to be able to charge a small fee for the content to be able to produce it due to the high costs of production.

"So I decided to use my programming skills to design and implement our own website. We both came up with a name after asking several friends. We have yet to recover our initial investment, but we enjoy helping others and are having a blast while doing it.

"We try to keep our episodes inexpensive, informative and entertaining at the same time. SmackTalk RC offers something for every audience, from the very beginner to the expert, from the 15 year old to the 50 year old.

"We are very thankful for having such a great audience and look forward to releasing many more videos in the future."

Thanks, guys, for all the hard work you put into helping fellow pilots; you never hesitate to do so when you see them at events. Now with SmackTalk RC, they can go online to get the same great advice you share at flying fields all over the planet.

Thanks to you for checking out the helicopter column this month. I will be back here in 30 days. MA

Sources:

Transcribed from original scans by AI. Minor OCR errors may remain.