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I'm building an FT Tiny Trainer. Currently it's just a chuck glider, but now that I have tested it, I want to add electronics. At first, the plane would be a controlled glider, but then I'd probably add a motor. So far, I've figured out what transmitter/receiver I want.

However, I am clueless about motor/servos/battery. FliteTest have "power packs" on their store, but I don't live in America and the shipping would be horrendous. I also don't want to just buy the parts in these packs from other places - my local hobby shops wouldn't have the specific ones I need, and I'd rather avoid buying online altogether. Instead, I want to find what parts I need (servos, motor, etc) and then go down to my local hobby shop and buy them.

My question has two parts, but they link together into one answer.

  • The first half of my question is: What electronic components do I need to make a plane fly?
  • The second half is: How are they linked together? What plugs into what?

A diagram would be lovely.

Also, I presume I'd need to learn to solder to do this, please correct me if I'm wrong.

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The main things you need are a motor, battery, electronic speed controller (ESC) and servos.

The ESC sits between the battery and motor, and it also has a thinner cable that goes to the receiver. The wires from ESCs are often labelled, but if not, there will be two big wires on one end that are the input from the battery (red for positive, black for negative), and three big wires on the other end that supply the motor. The motor wires can be any colour and it doesn't really matter how you connect them. If the motor runs backwards, switch any two motor wires. The cable to the receiver will be three wires joined together in a ribbon, similar to the cable on servos (and with the same plug)

The ESC also provides 5v to power the receiver and servos. All the positive and negative pins in the receiver are connected. The part of the ESC that does this is known as a BEC or 'battery eliminator circuit' because 'back in the day' you needed a separate 5v battery for the radio.

Servo cables have three wires, positive, negative and signal. Positive is in the middle so that plugging it in backwards doesn't cause short circuit. Servo plugs are pretty standard, although some have a little tab on one side to prevent them being reversed - but this requires that the receiver has a slot for the tab (and many don't, and the tabs get cut off).

Servo plugs are small and need a special crimp tool to make, so they are nearly always done for you - and they all use the same pins, so different brands are compatible.

You might also want plugs to connect the motor and ESC, either because the design routes the motor wires through the firewall, or so you can move components between models. 3.5mm bullet connectors are pretty standard here, with the male plugs on the motor (so you can safely power up an ESC without a motor).

If you shop carefully, you can probably find an ESC and motor with all the relevant plugs already attached but many only have the servo plug, either to reduce cost or to provide you with more choice. If it comes without plugs, or you need to change a plug, you will need to solder.

The Tiny Trainer is just about able to use the little red JST battery plugs that use the same pins as servo plugs, but it's right at the limit and old plugs tend to overheat, melt and short circuit. XT30 plugs would be a safer choice. XT60 plugs are much bigger than you need but a common standard for chargers and larger models. There are lots of other types of plugs these are the most common now.

Beware that the connectors such as the motor plugs or XT60 battery plugs require a larger soldering iron than the 20w irons that are usually sold for hobby electronics. Also, if you're soldering, you'll need some heat shrink tube to cover the joint. 5mm diameter fits XT60s and 3.5mm motor plugs. Remember to put the tube on the wire before you solder the joint, and slide it away from the heat or it'll shrink before you are ready.

If you are lucky enough to have a local hobby shop, they are usually very helpful in finding parts that will work together. Take a list of the recommended gear and they'll find equivalents, and may even do the soldering for a small fee.

When you're in the hobby shop, buy some spare props, some piano wire for the pushrods, control horns and swing keepers to make the attaching the push rods easier, and some Velcro strap to hold the battery in place. And a battery charger (with power supply). And some screws to hold the motor to the firewall.

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    $\begingroup$ I've accepted this answer as it gives the most detail in the connections. I would have loved to accept all of them, as they all have important info, but this is the most useful to me. $\endgroup$ – ThatCoolCoder Nov 18 at 20:28
  • $\begingroup$ Thanks! This is a fairly common question - I remember it puzzling me, even when the LHS had found me everything I needed. If there's anything the other answers did better, let me know and I'll merge it in here. $\endgroup$ – Robin Bennett Nov 19 at 9:11
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The image below shows a fairly basic fixed wing electronic configuration. Depending on your design you might not need it all, and for more complicated builds with flaps and retractable gear you would want more, but I think it is a good overview.

For the most part, you should not need to solder; most hobby electronics comes with common connectors pre-fitted so it is just plug and play! (Although, it is a handy skill to have anyway; and while you can buy most things you will need, being comfortable making your own cables, etc. might save you a little money down the line!.)

Your flight battery will normally connect to the Electronic Speed Controller, as the voltage is often too high to connect directly to the receiver and this allows maximum current delivery to the motor.
The ESC includes a voltage regulator so, if you are building a glider first, you will need to replace this with another voltage regulator or Battery Eliminator Circuit (BEC) - or, as the power requirements for a glider are much lower, you could opt for a lower voltage battery you can connect directly to the Receiver.

Your servos will normally fan out from the receiver. (There are some new technologies that use a digital bus to control the servos, but this is still less common.)
Some models do not have three axis control, so just don't install those servos ... and some (normally larger) designs have multiple servos per surface to provide enough force so just double them up.

When choosing a radio kit, you will want to look at the number of 'channels' it has. Four is typical (throttle, pitch, roll, yaw) but it is worth thinking about if you may want more in the future (e.g. flaps) as if your budget allows, it might be better value to spend a little more at the start than getting new kit later.

enter image description here

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  • $\begingroup$ By the way, I was planning on getting a 7 ch transmitter/receiver $\endgroup$ – ThatCoolCoder Nov 18 at 20:29
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Summary

  1. The necessary electronic components: Transmitter & receiver, ESC, motor, servos. (yes, it really is that simple)
  2. How they are linked together: basically; battery plugs into ESC input, ESC plugs into receiver, servos plug into receiver, and motor plugs into the ESC output.

Detailed explanation

The construction of a fixed wing can be fairly straightforward compared to a multirotor because it doesn't require any flight controller, and soldering is not even necessary in some cases. Although, considering the fact that you would prefer to buy components from a local hobby shop, I would expect there to be some soldering.

If you are making a controlled glider first, you will need a few servos and an ESC to go along with your transmitter & receiver. When you decide to make a powered aircraft, all you will need to add is a motor.

diagram

  • ESC: You'll need a 20-40 amp ESC with a 5-6v BEC. The BEC should be able to provide at least 2 amps. (Example)
    The ESC is responsible for supplying power to all of the electronics. It supplies power directly to the motors, and its BEC supplies power to the receiver and servos. The ESC has a Futaba JR connector with Ground, 5V, and Signal that plugs into the receiver. The ESC will need a connector that matches the battery. You may need to solder a connector onto the ESC.

  • Servos: You will need at least 3 servos for the Tiny trainer. An adequate servo size is 5-9 gram servos. (Example)
    Each servo will operate a control surface. Having 3 servos will allow you to have ailerons and elevator. You can add rudder if you have four servos. Each servo connects to a specific channel on the receiver via a Futaba JR connector. You can usually setup channel mapping on the transmitter so that the servos function correctly.

  • Motor: The recommended motor size is 1806 with 2280Kv. You can use anything close to those specifications. (Example 1) (Example 2) (Example 3)
    There is a wide variety of motors that will work. You just need a motor that will physically fit on the plane and has a reasonable Kv for the voltage. The motor connects to the three output wires on the ESC. You may need to solder the motor wires if the ESC or motor does not have banana connectors. If the motor spins the wrong way, just switch any two motor wires.

  • Battery: The recommended battery is a 3s 850mah LiPo. Depending on your electronics, you may be able to use a higher voltage or larger battery. (Example)
    The Battery powers all of the electronics on the aircraft. the Battery needs to have a voltage that the ESC can tolerate. The Battery also should not be to large, or it could strain the motor or make the aircraft sluggish. For the Tiny Trainer, I would not go larger than 1300mah.

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