Jan 252015
 

Here a list of what I would recommend someone who looks into RC, mainly for multi-rotors as those are quite en vogue currently. Lots of links

General FAQ

  • 2km, indoor models 100m, with proper antennas more than 100km
  • 50 km/h
  • US$100 to start minimal (good toy grade), US$500 for something more generic and re-usable (hobby grade). There’s no limit for professional equipment.

Some Definitions

  • Multirotor is anything which is not an airplane and has more than 1 rotor/propeller. Typical is quadcopter (AKA quad) as it’s the most simple one, thus most popular.
  • Multirotors have clock-wise (CW) and counter-clock-wise (CCW) spinning motors and the propellers need to match. While motors can spin any direction, the propellers have a top and bottom, so you need both CW and CCW propellers.
  • Helicopter have usually 1 large rotor and 1 smaller rotor to control yaw.
  • Fixed pitch (FP) helicopters regulate up/down via spinning the main rotor faster/slower. Don’t fly those outside with wind. Multirotors are usually fixed pitch type.
  • Collective pitch (CP) helicopters regulate up/down via changing the attack angle of the main rotor blades. The rotors spin at a constant rpm. Very agile. Challenging to fly. But you can do things like flying upside-down. Not recommended for beginners.
  • LOS is Line of Sight: You watch the thing you fly.
  • FPV is First Person View: You see what the camera on the thing you fly sees. Interesting point of view at times and it’s easier to learn orientations, but unless you know what you do, you need someone watching (via LOS). In some countries this is mandatory, so technically you cannot fly FPV alone.

Beginner Stuff

If you don’t know if you want this as a permanent (or at least longer term) hobby, get a feel for it first. I started with a US$30 RC helicopter.

  • Start with a small quadcopter (Ready To Fly AKA RTF): They are cheap, fly well, are not easy to break, and if, they are cheap to repair. I recommend to buy 2 (but not 2 transmitters).
    • Hubsan X4 (various versions): Flies well, can have brushless  (H109) or FPV (H107D). US$50-200. Flies well, hard to break, and you can get replacement parts.
    • Walkera Ladybird with and without FPV. US$60-200. Stable, works. I have the older non-FPV model. I like it. You can get a “proper” RC transmitter which you can re-use for larger models too.
  • For reference: this is what I started with. Not a quadcopter though. The first quadcopter I built broke within the first week.
  • Do not buy anything in toy shops or department stores. Those RC models are bad and expensive. Often both.
  • Read a lot. Forums are great and offer a lot of good information and helpful people in case you actually have a problem which is not yet solved. Good forums are RCGroups, and for FPV FPVLabs.

So you can fly and want more…

Once you know that this is not a fad-of-the-week, get something larger for outside. The above models you can keep for flying at home or when there is no wind outside.

Here some general rules:

  • Small is cheap. Too small is expensive again though. Stick to 200mm-300mm motor-to-motor distance.
  • Small is fast. Those small ones are nimble.
  • Large and heavy is stable in the air, and will break a lot more when it hits anything. And it’s more expensive to build and repair. I do not recommend large quadcopters for beginners. Once you can fly the small stuff, then go as big as you like.
  • Soldering is a really useful skill: if cables/connectors break, you can fix a lot by soldering. Without you have to buy replacements parts more often. Small electronic soldering iron is all you need. US$50.
  • Get a good set of screw drivers and hex drivers. M2/M2.5/M3 is most needed. Hex drivers are 1.5/2/2.5mm.
  • Get a usable battery charger. 50W output power is sufficient for a while. Usually they can use no longer needed 12V notebook power supplies. But check voltage and ampere. Make sure to get a charger which has balance ports and can charge 1S-6S (minimum 1S-4S). I have this one and it works well. I also have that one and it’s way better, but also way more expensive, especially as the power supply is a noisy 600W PSU.
  • Heat shrink tube. Use it. Nothing is worse than a short circuit with a LiPo battery. PlastiDip is ok too. Don’t forget that carbon fiber (CF) conducts electricity.
  • Apropos LiPo: Never charge them unattended. Never over-charge them. They will at least puff, and at worst burn. Don’t over-discharge either, but they’ll be “only” pretty dead then. Don’t keep them charged for days. Keep them cool (10°) for storage. Keep them warm (30°) for high performance. If they act funny or there’s doubt they work well, discharge and trash. If you have not figured it out by now: LiPo’s need some love. Have 4 LiPo’s. No need for more, but don’t have less than 2.
  • How much flying space do you have? X4/Ladybird need about 25m2 space. A 250 size quad about 400. FPV will require more space or it’ll get boring fast.
  • Don’t fly where children or dogs are. Both like to catch those funny things which fly in the air.
  • Never fly over people. If anything breaks, all quadcopters pretty much fall down immediately. It hurts when it hits someone on the head.
  • Transmitter: Futaba, JR, FrSky, Walkera, Spectrum. All work fine. Get what friends have. Initial setup is most difficult which is where friends can help. Afterwards it’s more personal preference.
    Obviously you need a matching receiver.
    I have a JR XG11 and I am very happy with it, but I’d get a Taranis if I had to get one now.
  • It is recommended and in some countries mandatory to have an insurance.

 Good Examples of Small Quads

Here 2 examples of small quads:

  •  Armattan CF226 or receiver-ready (AKA RXR: add receiver and battery only). The latter is US$265 and you won’t get much cheaper if you buy single parts yourself.
  • Tarot TL250. Needs 4 motors like those,  propellers like these or those, a flight controller (plenty available nowadays: Naze32, CC3D, MultiWii, APM, Naza), 4 motor controllers (ESC) like those. Some cables, heat shrinkand zip ties and other small stuff.
  • Typical LiPo is 3S 1300mAh or 4S 1000mAh.
  • Good camera for those is the Mobius. Small and light and hard to break.

 Something Bigger

If you want to carry a camera like GoPro or Sony, go for something a bit bigger. 6″ propellers help already. Frames for 8″ propeller and larger are plentiful. Some random examples are here, here, here, and here. Some RXR are this and this. Some of them can carry camera like the Sony Nex-5T including a gimbal.

FPV?

Before attempting FPV flying, get the basics down. The video link is an extra  item which can break and if it does, you need to fly LOS. So make sure you can fly LOS first.

Too easy?

If you can fly your multirotor like this, and FPV like that, then get a CP helicopter and learn to fly like that here. Should keep you busy for a year. Or ten.

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