Safety Comes First
Dave Gee | [email protected]
Several safety-related reader stories are featured this month.
Also included in this column:
- A clever engine-starting safety idea
- Responses to smoking in the pits
It's story time
I have a stack of great email to share, starting with the following from Frank Slavin.
About two years ago I took two electric airplanes to the field—both on the same frequency. After flying one, I parked it under my car. A club member test-flew my second airplane.
As I watched, another member asked me where my first airplane was. Going over to my car, I noticed that airplane number one had taken off and crashed into the plate-steel clubhouse.
There is a moral to this story: don’t forget to turn your switch off after you fly your electric airplane—unless you want to practice formation flying.
I can relate to that one, Frank! A few times I have found switches on as I put my models away. Double-check this stuff!
Joe Wagner — improvised starter protection
Following is a clever idea from Joe Wagner—MA’s "The Engine Shop" man. He wrote:
Experience is what you gain immediately after it was needed. While spectating at a sport RC session, I was asked to help a man with a balky engine. No starter or "chicken stick" being available, I hand-flipped—and got bit.
Then it occurred to me that an excellent substitute for a "chicken stick"—or for the leather glove I use when hand-starting one of my own engines—can be quickly improvised by folding over a paper towel a couple or three times, then wrapping that around one’s index and middle fingers, retaining it with rubber bands or masking tape.
It’s better to wrap the fingers with a paper towel before flipping the propeller than to bandage the finger afterward. If someone as knowledgeable as Joe can get nicked, we all need to take extra care.
Eddie Graves — field-box batteries and hobby-knife safety
Eddie Graves wrote in, and, once again, I saw myself in the story. He related the following.
These are a couple of the things that I have observed or experienced myself (painfully in one case). First is a topic that you have covered several times, battery safety, but this doesn’t involve Li-Polys. This involves your field-box batteries.
I have observed twice in the last six years the rare and mysterious smoking field box. In both cases the battery was shorted and caused a small fire (from melting wire and burning painted wood). In neither case did the fuel that was attached to the box catch fire and both were quickly contained.
I guess my biggest worry is people leaving their field-box batteries hooked up while they are unattended (stored at home in the house or garage). The terminals of the batteries (at least one) should be covered with something. (I use a connector by itself that hasn’t been crimped to anything—just a brand new connector.)
I would hate to see what could happen if the boxes had not been attended and the fire had been allowed to get to full potential.
The second topic is hobby-knife safety. This one comes from personal experience, and a bit of pain. It sounds like common sense (and is really). Put down the knife when you are going to do anything that does not involve cutting.
I was scoring a piece I was working on, and I figured that it would be easy enough to break the two pieces apart, so I decided (or really just didn’t think about it) to break them apart while still holding the knife in my left hand.
Well, after I removed the buried blade from my right forearm, I realized that it took a little more force to break those pieces apart than I thought. I am now current on my tetanus shot and have a nice little numb spot on my wrist from nerve damage.
Thanks for the reminder, Eddie! My bad habit is holding a running rotary tool while brushing sawdust away or rearranging something. Dumb! I’m making a real effort to catch myself and change this, or I could end up typing with nine fingers instead of two.
Christopher Singleton — rotary-tool tips
Christopher Singleton is an experienced user and kindly jotted down some tips for getting along with these useful gadgets.
The following are based on my experiences with working with rotary tools as an architectural model builder 15 years ago:
- Always wear safety glasses, and wear a face shield when using cutoff disks. Disks do indeed shatter if you apply twisting force to the blade.
- Use a cutoff disk when cutting metal. Unless you have fingers to spare, do not use a toothed blade. A cutoff disk is a miniature version of the same cutoff disks used in the metal-cutting industry. A cutoff blade is a miniature circular saw, and some manufacturers have stopped selling them because of liability concerns.
- Rotary tools work great on wood, metal, ceramics, and glass (etching). However, even their lowest settings are generally too fast for use on plastics (styrene, acrylic, and polycarbonate).
- Typically if you try to use a 1/4-inch-diameter or larger sanding drum on plastic you will generally find that you are melting the plastic. Smaller-diameter burrs are generally okay, but light pressure is needed.
- When possible use a collet rather than a three-jaw chuck, which has a tendency to loosen, especially when under heavy load.
Other than the above, I couldn’t live without my two rotary tools.
I agree with Christopher regarding miniature saw-blade tools. They are marvelously useful but require great care. I’ve found that the better-quality blades are well worth the cost compared to flimsy bargain products.
Hugo Yacoucci — precision and care
Another seasoned power-tool man is responsible for the teensy propeller bearing in one of this month’s photos. Hugo Yacoucci does beautiful work, and his careful, methodical habits allowed him to have a long career in machine-shop work while retaining all of his fingers, not to mention his keen eyesight.
Don Burke — personal protective equipment
I snapped a picture of CL flier Don Burke at a local contest. He doesn't have time to waste with injuries, so he uses proper personal protective equipment down to a shade hat for the California sunshine. He's an excellent pilot too, which is why I was taking pictures rather than competing.
Spectator safety at hobby shows
Another picture shows the backs of fascinated spectators at a hobby show. They can get a close look at the newest RC helicopters, thanks to a sturdy net barrier.
Those factory demonstration pilots are among the most skilled in the world, but they still understand the need for precautions, just in case. That net pleased the crowd and the insurance company.
Ken Scholz — a slope-glider close call
Ken Scholz emailed his learning experience to me for our benefit. His flying site is a truly beautiful spot, but don't let that distract you from keeping an eye out!
I'd like to relate one of my "lack of good judgment" experiences. Years ago I was flying my first aerobatic slope glider at Coyote Hills at the southern end of San Francisco Bay. The sun was low in the sky, reflecting off the bay, and limited me to using only about half the slope. Everyone else had gone home and the summer wind was probably over 30 kts.
I tried to avoid the sun, but being new to an airplane of this performance level, mistakes were made and I found the airplane flying right into it. I closed one eye, waited, and in a few moments it reappeared on the other side, and I resolved more than ever to keep it on the half of the slope that I could see.
In a few minutes it happened again, and again I confidently waited for it to reappear—only this time I waited, and waited, and waited. I had been flying high and well out from the slope and after some time it dawned on me that if the Coyote was still flying it either had to be flying straight away from me toward the bay or straight toward me.
I shaded my eyes for a closer look, saw a shape, and ducked to the right as the nose grazed my ear and the wing delivered a blow to my shoulder like a hard punch. The airplane probably was traveling over 60 mph and easily could have penetrated my skull. How many mistakes can you identify here?
Ken's close call is a lesson to all outdoor fliers. As the fighter pilots used to say, "Beware of the Hun in the sun"!
Contact and corrections
Remember that you don't need email to contact me; real letters can be sent to Box 7081, Van Nuys, CA 91409. Your correspondence is always welcome, and please don't hesitate to let me know if I'm wrong about something. I work under the handicap of not knowing everything, so your help is appreciated.
Smoking in the pits
I received exactly two emails from readers who took issue with my condemnation of smoking in the fueling areas. Although I agree that model-airplane fuel is fairly hard to ignite with a cigarette, particularly when in sealed metal cans, I maintain that there is no excuse for lighting up in the pits when fuel is present. Why take the chance when the risk is zero just a few feet away?
Spilled gas, lit matches, leaky tanks, and invisible fumes can and do come together, and people get hurt. This is not an anti-tobacco rant—just a safety rant.
Li-Poly battery safety
I have been reminded of the continuing need for education about Li-Poly batteries. Again, these batteries are wonderfully light and powerful, but they require much more caution than Ni-Cd cells.
- Do not charge them without being there watching.
- A "crashed" pack is suspect and may puff up and explode at a later moment.
- Charging must not be done indoors or in a vehicle; a clay pot or a bucket of sand is the best place to put a pack while charging.
Nearly everyone I know who has upgraded to these cells has experienced a damaged pack, and some have resulted in structure and vehicle fires. Please don't take shortcuts!
MA
Transcribed from original scans by AI. Minor OCR errors may remain.
