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Post by Grug - American Neanderthal on Nov 6, 2006 8:19:05 GMT -7
I have had some people asking about getting started in RC, They are interested in electrics. Being a hydrocarbon polluting kind of guy, I know next to nothing about electrics.
I thought maybe some here know a little about them and give some ideas of what to recommend.
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Post by jetmex on Nov 10, 2006 10:04:07 GMT -7
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Post by ctdahle on Nov 12, 2006 11:25:34 GMT -7
I'm currently recommending Hobby Lobby's "Mini Telemaster" combination to start with electrics. I'm suggesting an upgrade to a four channel radio. I have several almost-teen-agers who will be getting this for Christmas.
Telemasters are really nice flying models, and make good trainers for people who have a bit of help from a competent flyer.
I still think that beginners, especially the young ones, should build their first airplane. But that's because I am a teacher and I think they all need to learn how to read and follow techinical instructions.
Sig is selling an electric version of the Kadet, and I think it would be a pretty good choice, but I haven't found anyone who is selling a good combination set up.
Electrics are still a bit of a black art, so I rely on hobby shop recommendations to get the right combination of motor, prop, batteries and speed controller. Someday, I hope to be able to look at an airframe and recommend a power supply combination with the same authority that I do with a glow fuel powered model, but that's going to take a lot of models and mistakes.
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Post by Grug - American Neanderthal on Nov 12, 2006 12:30:44 GMT -7
Thanks for the pointers, its so out of my realm of experience I don't even know what to tell people to start from.
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Post by trimtab on Nov 12, 2006 21:23:52 GMT -7
Looks like electric motors are expensive.
About five years ago, I watched a scale four engined Pan Am Clipper with electric power fly off a lake. It was a real nice looking model until it flew and the realism evaporated. For a scale model, it sounded unnatural as it hummed around the sky flying at near scale jet speeds. Later, the owner had problems with the motors starting up unexpectedly and running at full speed while it sat in a cradle on the shore.
The P5M flew that day, JATO and all. What a sight that was.
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Post by ctdahle on Nov 13, 2006 22:25:31 GMT -7
The motors themselves are cheap. It's the batteries and the esc's that are expensive...and the chargers.
The Telemaster deal above, is actually cheaper than outfitting a comparably sized glow model, including the ground support gear, however, if I was not trying to do it completely on the cheap, I'd say get an extra charger and two extra battery packs.
The big problem, I think, is that you need several sets of batteries to swap out if you want to fly continuously. When I take my electric out, I have two packs, which allow me to make 2 consecutive flights before I have to wait for batteries to charge. After that, it's about a 15 minute wait between flights. The batteries need to cool off between flying and charging. The esc's start to act funny if they get hot too.
Best way to do electrics in my opinion is to have two planes, two chargers and two battery packs for each plane. That way the battery and esc that just flew are cooling, two batteries are on charge, and the fourth battery just came off charge and is in the active airplane.
I primarily fly electrics in the winter. Overheated batteries are not really a big deal when it's ten degrees. I put the hot battery inside my TX glove to warm my fingers while I wait for the other battery pack to finish charging.
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Post by Grug - American Neanderthal on Nov 14, 2006 6:27:59 GMT -7
Heheh, well there goes the budget. the 2 things that have kept me from going the park flyer route is the battery charge time thing and wind. We don't have that many relatively calm days to use them. Going a little bigger, there is no saving over glow, especially since I have all the glow stuff already.
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Post by jetmex on Nov 16, 2006 11:25:19 GMT -7
Chris is right, it's not the motors that will hurt your wallet, it's the speed controls, batteries and chargers. There really isn't much difference in the cost, but a glow to electric conversion on anything 40 size and up could put a big crimp in your Christmas budget. My electric Me-109 for example -- $95 for the kit (on sale, of course), $135 for a 2 cell lipo, speed control and brushless motor. Still don't have a charger, that should be another $50-100, depending on how fancy I want to go. The price of radio and servos not included..... The advantage of an electric for me is that I can fly closer to home (or in the hangar at work). If I can afford it. I'm sure the cost comes down quite a bit once you acquire all the stuff....
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Post by Galvin on Dec 8, 2006 8:18:26 GMT -7
Most of the stuff I have now is electric and ranges from my Alfa MiG-15 (one of the most fun and challenging airplanes I have ever had) powered by a 400 size high speed motor to a 76" span Great Planes Curtiss P-6E that would normally be powered by a 1.20 size motor.
It is powered by one of the largest "outrunner" motors made (it swings a 23" prop) and uses a 90 amp controller. My Army P-6E is presently being converted to the radial engined Navy F11C-2 "Goshawk" version at this time. And yes, the power setup IS very expensive but it is unlikely to wear out any time soon either.
Once you have all the chargers and other goodies and get comfortable with the principles of electric flying it is pretty hard to drag out one of your oily internal combustion powered airplanes when you know that a significant amount of your time will be spent in cleaning it up at the time you just want to go home.
If I had any real complaint to make it would be that I have invested a lot in NiCad and Nickle Metal Hydride batteries and chargers. I and am now converting over to Lithium Polymer (LiPoly or LiPo) batteries that weigh about half as much and give higher power for much longer flight times. They are more critical to charge and take longer to do so at the lower charging amps required on their special charger. They are far more expensive and somewhat more delicate but 15 minute flight times and much better performance resulting from lower battery weights more than compensate for the added bother.
If LiPos do short out internally they can be dangerous, puffing up like the Pillsbury Doughboy at best or bursting into flame at worst. NiCads and NiMh batteries can have the same problems but with somewhat less dramatic results. LiPos require a special charger and more strict attention to charge rates than NiCads and NiMh batteries.
As far as the sound of electric models or, more to the point, the lack thereof, that is one of the major attractions of such flying. It allows one to fly electrics in places near residences and get literally no complaints from the neighbors.
For those who insist that the sound of a semi-muffled chainsaw lends an authentic note to model flying I would suggest that they go listen to a real airplane.
Gas powered models sound like anything from angry bees to someone blowing into a glass of milk with a soda straw and bear no relationship to full-size aircraft soundwise. My little MiG, on the other hand, is anything BUT quiet but has the advantage that the sound doesn't carry that far. The scream of the fan at nearly 50,000 RPM is pretty hair raising at full speed, which is by the way faster than most of the average gas models by a good margin.
On the other hand, there are now a couple of companies in Europe that are recording actual full-size aircraft engine sounds and several models are flying at this time that duplicate the entire range of sound of a real aircraft from the characteristic starting sounds through all the other phases of flight and even increase or decrease rpm with throttle movement. They are not that noisy either, being limited in the size of speaker they can carry and the design of the speaker box within the airframe. So far a V-12 and radial recording are available for those who absolutely have to have sound and a He-111 is flying in the UK that uses two of the V-12 setups and reportedly sounds VERY real.
Imagine if that Clipper had been flying with the sound of four Pratt and Whitney radials throbbing away..........
Can't get that kind of realism with a weed whacker drowning it out.
Average reliability of electric models over gas powered is better, especially the multi engined ones, where loss of one motor and its attendant serious control problems is far less likely. My Aeronaut Grumman Tigercat had many flights and was eventually sold to someone who supposedly doesn't fly it but has it on display somewhere. It did survive an electric lead coming unsoldered and a high speed descent into an almond orchard at the Chilliwack electric fly in a couple of years ago with literally no damage (it was flying again 15 minutes later) but that was a manufacturing defect in a commercial battery pack. I resolder all critical leads now.
The cheap "can" motors sold by Graupner through Hobby Lobby can give as much pleasure in simple models as the more expensive types but will eventually wear out.
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