A guide for multi-rotor newbies

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   The level of interest in multi-rotor aircraft has increased dramatically in the past couple of years. There have been heaps of noob posts in this forum in the past few months, and it seems that good information is spread out over many threads and can be hard to find. The purpose of this thread is to help people who have little or no multi-rotor (or RC) experience to buy the right equipment and successfully get an aircraft into the air. Hopefully this guide will de-mystify the process and help people through the process of selecting suitable components which work well together. 

I will try to update this post with more details as needed, and others are welcome to make suggestions for additional content. If it’s deemed useful, perhaps the mods might make it a ‘sticky’ to make it easy to find. Bear in mind that I am by no means an expert, just an enthusiast who likes helping people enjoy the hobby. I will not be held responsible for getting your aircraft working. 

Finally, I will be making references to HobbyKing products, which I personally use almost exclusively and have no qualms recommending. However, it should be recognised that there are many other sources of hobby parts, and you may find similar alternative products elsewhere. A few posts further down, you will find a parts list, with links to HobbyKing products, sufficent to build a complete quad-rotor aircraft. At time of writing, the complete kit costs about $175, not including postage costs.

If the concept of building an aircraft from scratch scares you, then you're probably in the wrong thread. 

You can buy an almost complete quadcopter kit here that will work fine, and save you a lot of time and hassle (funnily enough, HobbyKing's MultiStar kit was released some time after my parts list, but looks a lot like the one I collated).

If you'd prefer to just buy something that will fly straight out of the box with virtually zero assembly, then something like this will probably appeal to you more, and it's actually a really good (albeit relatively expensive) product.

But if you'd prefer to create your own custom build that will suit your needs and preferences perfectly, read on.

But before we get started, something that should be said to all new RC model pilots, particularly those who are interested in multi-rotors  for aerial photography and/or pursue FPV flight. 

PLEASE DON'T FLY LIKE AN IDIOT!

RC aircraft are a lot of fun, and a great hobby to be involved in. The challenge of building a functional and beautiful aircraft, the excitement of seeing it in the air and responding to your commands, the wonder of seeing the world from a different perspective - it's a marvellous feeling, and like many others here, I'm totally addicted.

But there's a more serious side to this hobby. An aircraft can be dangerous, both to yourself and to the public. A multi-rotor aircraft usually weighs well over 1kg, and has several sharp spinning blades - it could easily cause serious damage to a car, a building or another aircraft. If it fell one somebody from a decent height, they could be seriously injured or killed.

Please, don't fly like an idiot. Keep your aircraft well under control, and fly in open areas well away from people, cars and buildings. Don't attempt manoeuvers that are beyond your skill level and experience. Don't fly in bad weather, or above crowds of people. Don't make lots of noise that will annoy your neighbours. Don't fly over private property without permission, or swoop people or animals with your aircraft. Irresponsible and foolish behaviour can easily get RC aircraft banned from city parks and other public areas. You could spoil if for everyone if you're not careful.

If you're an FPV pilot, or doing aerial photography, you need to be especially careful. The general public is very uneasy about the idea of "drones" spying on them, and concerns about privacy and safety are growing every day. Many governments are being urged to implement licensing, heavy restrictions or even outright bans on the use of aircraft-mounted cameras, in part due to the foolish actions of an inconsiderate minority. Flying your aircraft in an irresponsible way will just make these problems worse, and turn public opinion towards further restrictions. 

Please respect people's expectations of privacy, and gain a full understanding of the limitations of your equipment. Use video frequencies and equipment power levels that are legal in your country. Don't fly FPV without a spotter/helper to keep an eye on your aircraft's position relative to people and hazards - you can't see behind your camera. Remember that your actions will reflect on this wonderful hobby as a whole, and we'd all like to be able to enjoy it for a long time to come.

Now that's over with, lets get on with the fun stuff.

What are all these parts for?

A brief explanation of what all the major parts do:

Frame - the structural component of your aircraft, keeping everything where it belongs. All of your components will be connected to your frame in some way. 

Control board - the "brains" that keeps your aircraft steady in the air, and translates the pilot’s commands into movement. It uses various sensors and a micro-processor to determine what your aircraft is doing, and makes adjustments to the aircraft’s motor speeds to keep it controllable.

Radio receiver - Receives commands from the pilot’s radio and relays them to the aircraft’s control board.

Motor and propeller - create thrust and lift from stored electrical energy.

Electronic Speed Controller (ESC) - convert DC power from the battery to AC power to the motors. By varying the current and timing of electrical pulses, the speed of the motor can be changed.

Battery - the source of electrical power for all the other components. The size of the battery can vary widely, depending on the number of motors, the size of the motors, the weight of any payload and the flight time desired.

Power distribution board - a simple circuit board which makes connecting multiple ESC’s wiring to the same battery simple and neat. This can also be made from cables, particularly for large aircraft with high current. Some frames have power distribution circuitry built into the frame.

Edited by klaw81 - 27/Aug/2014 at 8:15am

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klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Topic: A guide for multi-rotor newbies Posted: 05/Feb/2013 at 1:25pm
	The level of interest in multi-rotor aircraft has increased dramatically in the past couple of years. There have been heaps of noob posts in this forum in the past few months, and it seems that good information is spread out over many threads and can be hard to find. The purpose of this thread is to help people who have little or no multi-rotor (or RC) experience to buy the right equipment and successfully get an aircraft into the air. Hopefully this guide will de-mystify the process and help people through the process of selecting suitable components which work well together. I will try to update this post with more details as needed, and others are welcome to make suggestions for additional content. If it’s deemed useful, perhaps the mods might make it a ‘sticky’ to make it easy to find. Bear in mind that I am by no means an expert, just an enthusiast who likes helping people enjoy the hobby. I will not be held responsible for getting your aircraft working. Finally, I will be making references to HobbyKing products, which I personally use almost exclusively and have no qualms recommending. However, it should be recognised that there are many other sources of hobby parts, and you may find similar alternative products elsewhere. A few posts further down, you will find a parts list, with links to HobbyKing products, sufficent to build a complete quad-rotor aircraft. At time of writing, the complete kit costs about $175, not including postage costs. If the concept of building an aircraft from scratch scares you, then you're probably in the wrong thread. You can buy an almost complete quadcopter kit here that will work fine, and save you a lot of time and hassle (funnily enough, HobbyKing's MultiStar kit was released some time after my parts list, but looks a lot like the one I collated). If you'd prefer to just buy something that will fly straight out of the box with virtually zero assembly, then something like this will probably appeal to you more, and it's actually a really good (albeit relatively expensive) product. But if you'd prefer to create your own custom build that will suit your needs and preferences perfectly, read on. But before we get started, something that should be said to all new RC model pilots, particularly those who are interested in multi-rotors for aerial photography and/or pursue FPV flight. PLEASE DON'T FLY LIKE AN IDIOT! RC aircraft are a lot of fun, and a great hobby to be involved in. The challenge of building a functional and beautiful aircraft, the excitement of seeing it in the air and responding to your commands, the wonder of seeing the world from a different perspective - it's a marvellous feeling, and like many others here, I'm totally addicted. But there's a more serious side to this hobby. An aircraft can be dangerous, both to yourself and to the public. A multi-rotor aircraft usually weighs well over 1kg, and has several sharp spinning blades - it could easily cause serious damage to a car, a building or another aircraft. If it fell one somebody from a decent height, they could be seriously injured or killed. Please, don't fly like an idiot. Keep your aircraft well under control, and fly in open areas well away from people, cars and buildings. Don't attempt manoeuvers that are beyond your skill level and experience. Don't fly in bad weather, or above crowds of people. Don't make lots of noise that will annoy your neighbours. Don't fly over private property without permission, or swoop people or animals with your aircraft. Irresponsible and foolish behaviour can easily get RC aircraft banned from city parks and other public areas. You could spoil if for everyone if you're not careful. If you're an FPV pilot, or doing aerial photography, you need to be especially careful. The general public is very uneasy about the idea of "drones" spying on them, and concerns about privacy and safety are growing every day. Many governments are being urged to implement licensing, heavy restrictions or even outright bans on the use of aircraft-mounted cameras, in part due to the foolish actions of an inconsiderate minority. Flying your aircraft in an irresponsible way will just make these problems worse, and turn public opinion towards further restrictions. Please respect people's expectations of privacy, and gain a full understanding of the limitations of your equipment. Use video frequencies and equipment power levels that are legal in your country. Don't fly FPV without a spotter/helper to keep an eye on your aircraft's position relative to people and hazards - you can't see behind your camera. Remember that your actions will reflect on this wonderful hobby as a whole, and we'd all like to be able to enjoy it for a long time to come. Now that's over with, lets get on with the fun stuff. What are all these parts for? A brief explanation of what all the major parts do: Frame - the structural component of your aircraft, keeping everything where it belongs. All of your components will be connected to your frame in some way. Control board - the "brains" that keeps your aircraft steady in the air, and translates the pilot’s commands into movement. It uses various sensors and a micro-processor to determine what your aircraft is doing, and makes adjustments to the aircraft’s motor speeds to keep it controllable. Radio receiver - Receives commands from the pilot’s radio and relays them to the aircraft’s control board. Motor and propeller - create thrust and lift from stored electrical energy. Electronic Speed Controller (ESC) - convert DC power from the battery to AC power to the motors. By varying the current and timing of electrical pulses, the speed of the motor can be changed. Battery - the source of electrical power for all the other components. The size of the battery can vary widely, depending on the number of motors, the size of the motors, the weight of any payload and the flight time desired. Power distribution board - a simple circuit board which makes connecting multiple ESC’s wiring to the same battery simple and neat. This can also be made from cables, particularly for large aircraft with high current. Some frames have power distribution circuitry built into the frame. Edited by klaw81 - 27/Aug/2014 at 8:15am

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 05/Feb/2013 at 1:27pm
	What are you trying to do? The very first step in building a multi-rotor aircraft should be to decide what you want it to be able to do. Some people just want to fly around, some want to carry cameras or other payloads, some want to do aerobatics, some want to build an automated drone aircraft. An aerobatic aircraft will not be very good at carrying a heavy payload, and vice versa. So you need to make this decision first - all of your component selections will depend on this decision. Pick your brains The next step is to determine which control board your aircraft will use. The control board is the "brains" that will keep your aircraft steady in the air, and translate your commands into movement. Control boards range from basic $15 control boards to very expensive boards with autopilot, advanced self-stabilisation and camera gimbal controls costing several hundred dollars. Since this is a noob guide for those who have never played with rotor craft before, I'd recommend the KK 2.0 control board to begin with. It's relatively cheap at ~$20, it can be configured for various motor configurations, it has sufficient sensors to be reasonably stable out of the box, and it has a built-in setup routine on an LCD screen to walk you through the setup process. For the quickest route to getting into the air, this is easily the best choice. You might also consider a MultiWii control board, which is slightly more expensive but includes a few extra sensors for additional stability and can be expanded with additional capabilities in the future. The compromise is simply that it's more complex to configure for your aircraft, and it may require some trouble-shooting to make it work for you. Keeping it together Next, we'll need to select a frame. Frames need to be strong enough to withstand the forces of opposing motors without flexing and cope with rough landings without breaking. Meanwhile, it must also be light enough that your motors can easily lift it, and ideally have a small aerodynamic profile to avoid being too affected by wind. Frames may also be required to dampen vibration, or to support a camera or other equipment. Your frame selection will depend on what you want your aircraft to do. For the sake of simplicity, I’ve assumed you’re going for a 4-motor craft, commonly referred to as a quadcopter. If you want your multi-rotor to be agile and aerobatic, a small light and strong frame is a must. Look for a frame that’s light (around 350 grams, or less if possible) with a diagonal motor-to-motor measurement of 400-500mm. Carbon frames will probably be best. For those wishing to carry a small video camera for FPV or aerial videography, stability and space for a payload is most important. Look for a nice strong frame with a diagonal motor-to-motor measurement of 450-700mm. You might want to consider different shape configurations, such as H-quads or V-tails, in order to move the motors away from your camera’s field of view. For those wanting to carry a large heavy camera, weight-carrying capacity and stability tend to be most important. You will need a large, sturdy rigid frame which is designed to carry an under-slung camera gimbal. You probably should consider using more than 4 motors too; 6- or 8-motor craft are very common in this application. Honestly, this should NOT be your first multi-rotor. Learn to fly with something smaller - a newbie will be totally overwhelmed with the setup, tuning and complications of such a complex craft. Edited by klaw81 - 05/Feb/2013 at 1:58pm

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 05/Feb/2013 at 1:31pm
	Picking powerplants This is a big subject and rather long-winded, so please bear with me. Choosing the right motor is important for good performance in any aircraft, but it’s particularly critical in a multi-rotor aircraft where your aircraft is literally hanging in the air, suspended under rotors. With the sheer number of motors available, and the array of different sizes, speeds and specifications for each motor, choosing suitable motors can be a daunting task. To begin the basic selection process, we need to how much thrust will be required to keep the craft in the air. The basic rule of thumb with multi-rotors is that your motors should be capable of producing twice the total flying weight of your craft in thrust. This “safety margin” ensures that your motors will be capable of responding quickly to your control inputs, or arresting a rapid vertical descent, even when your battery voltage is reduced over time. Our equation is therefore as follows: required thrust per motor = ( Aircraft weight x 2 ) / 4 motors So for a 4-motor craft, each motor must be capable of producing half the aircraft’s weight in thrust. No doubt you’re already seeing the problem with this equation – you don’t actually know what your aircraft will weigh yet! Fortunately we can make some educated guesses to get us in the ballpark. For the purpose of estimation, we can assume that each motor and its accompanying propeller weighs 100 grams – a total of 400 grams for 4 motors. Add the weight of the frame, which is likely to be around 450-500 grams. Add another 300 grams for the battery, and another 100 grams for the 4 ESC’s and their wiring & plugs. And your radio receiver, control board and wiring will probably weigh another 50 grams or so. If you’re carrying a payload, such as a camera or other special equipment, you’ll need to add that as well. For the average quadcopter, the total flying weight is likely to be around 1.3kg. Using the equation above, we now know we’re looking for a total thrust of 2.6kg, or 650g per motor. We now know we’re looking for motors weighing up to 100 grams, which can generate at least 650 grams of thrust using a 3-cell battery and a propellor of 8-12 inches diameter (see more on this below). For aerobatic aircraft, you should be looking at motors of around 1000-1400kV and relatively small propellers. These will make your aircraft more responsive and allow flips and other aerobatic manoeuvres, at the expense of being a little more difficult to control. For larger multi-rotors, or aircraft carrying payloads, large propellers and low-kv motors work best. These have more rotational momentum, and will more easily maintain your aircraft’s stability. Look for 700-900kv motors capable of making the thrust you need. For all but the largest craft, assume you will be using a 3-cell battery to begin with. You can upgrade to a 4-cell later if needed. Multi-rotor craft commonly use 2-bladed slow-fly type propellers, 8-12 inches in diameter and with a pitch of 4 to 6 inches. Propeller selection is very important and can be a bit tricky. We’ll talk about that more later - just use the above sizes as a guideline to help with motor selection. You’re now ready to start looking for motors. The list of specifications for each motor on HobbyKing can be daunting, but try to check for the following items on each motor: 1. Weight - 100 grams or less 2. Voltage - 3-cell (11.1V) generally what you’re looking for 3. Motor speed (kV) - choose according to the speed guidelines above 4. Thrust data - this is sometimes missing from the product description, but can often be found in the reviews or comments. Look for thrust data for the voltage and prop size as per the guidelines above. A few hints to make it easier.. HobbyKing enthusiasts will already be familiar with the site’s Motor Finder, which is a helpful database for the vast array of motors HobbyKing offers in a semi-logical fashion. For a start, look for motors of around 21-30mm size that meet the thrust, weight and speed guidelines discussed above. You may need to go up or down a size, depending on the weight of your specific aircraft. You may also find it helpful to read the blogs and threads made by others who have built similar craft in the past. Look at the motors and components they've selected - they may also be suitable for your needs. Finally, take special care to save weight where possible. Low weight is very important for all aircraft, and should be a major factor in every component selection. Any excess weight will be quadrupled, because you need 4 motors - and every extra gram is lost battery life and reduced maneuverability. Edited by klaw81 - 06/Feb/2013 at 6:15am

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 05/Feb/2013 at 1:32pm
	Choosing a speed controller Once you've picked out the motor you will use, you also need to select the Elecrotronic Speed Controller (ESC) that will run it. Thankfully, this task is much simpler than motor selection. ESCs are primarily rated for the amount of current they can constantly supply to the motor. Some may also have a "burst current" rating, but this should be ignored for now. Determine the maximum current draw from your chosen motor's specifications. Add a 10% safety margin, and look for ESCs rated for at least this amount of current. You will also need to check that your chosen ESC is rated for the correct number of battery cells (usually 3 cells or 11.V) and ensure that it's not too heavy. Once again, any excess weight will be quadrupled, since you need 4 of these items. Pretty much any ESC will work in your multi-rotor aircraft, but some will work better than others. Some of the higher-quality ESCs are capable of a faster "refresh rate" - the number of times (per second) at which they check for new instructions from the control board and adjust the motor's speed accordingly. A faster refresh rate means finer control, faster response to pilot input and ultimately, greater stability. HobbyKing sell a large range of ESC brands, but most of them are designed for fixed wing or helicopter applications where refresh rates are less important. The following brands are known to have a fast refresh rate and work well in multi-rotor applications: Turnigy Plush, Mystery and their clones, HobbyKing BlueSeries. More recently, HobbyKing has introduced the MultiStar ESC range, which are designed specifically for multi-rotor aircraft. For what is likely to only be a few extra dollars, getting quality ESCs is an excellent idea and highly recommended. Update: HobbyKing now sell a range of "Afro" branded ESCs, which are pre-installed with custom "SimonK" firmware. This firmware was designed by an enthusiast (look him up if you're interested) in order to get better performance from multi-rotor aircraft, and is widely considered to be the best firmware available. SimonK firmware can be installed on many different brands of ESC, but if you're building a new craft it's much easier to just buy the Afro ESCs that already include the software. I strongly recommend the Afro range as the best choice of ESCs available from HobbyKing. Be aware that you need 4 identical ESCs for your aircraft. It's possible to make a quadcopter fly with 4 different ESCs, but it will be more erratic and much harder to control. You might also give consideration to buying a programming card for your ESCs. This small, inexpensive tool will allow you to quickly and easily re-program your ESCs to behave in the correct manner. It's not mandatory - you can program ESCs manually - but the programming card does make things easier. Propellers It's a pretty simple job to select propellers, in theory. The specifications for your motor should indicate roughly what size you need, to create the thrust you're seeking. However, there are a few complications. The main issue is finding propellers which are available in both standard and counter-rotating arrangements. Multi-rotors have half the motors spinning clockwise (CW), and the other half will be spinning counter-clockwise (CCW) - thus effectively balancing out each other's torque for a stable equilibrium. To make it easier for you, HobbyKing sell a variety of sizes of propellers in CW and CCW bundles, ranging from 5" all the way up to 13" diameter. The complicated nature of fluid dynamics means that there are many factors in determining how effective your propellers are at creating thrust. Start with the size propeller recommended on your motor specifications, but feel free to experiment with different propellers if you like. Change the diameter by an inch, try a slightly different pitch, and see how it affects your aircraft's performance. You may find that battery life can be extended by up to 15% simply by finding the perfect combination of diameter and pitch. If you do decide to experiment, be careful to moniter your motor, battery and ESC temperatures. You can overload your equipment by using propellers that are too large. When you order propellors, make sure you order at least twice as many propellers as you need. Propellers are very easy to break when you're learning, and you will definitely need spares. Fortunately, they're relatively cheap to buy in packs. Get more than you think you need - it's very frustrating to be unable to fly simply because you don't have a spare propeller. Each of your new propellers need to be balanced before they're used on your aircraft. Slight flaws in the casting process mean that one blade of your propeller can be slightly heavier than the other, creating a vibration when the propeller is spinning quickly. Balancing simply adds or removes weight so that both blades are the same weight. This task only takes a minute or two with the right equipment, and it can dramatically improve the stability of your aircraft by reducing vibration that upsets your control board's sensors. I'd recommend buying a magnetic balancer (HobbyKing sells them for $15 or so) but you can also achieve workable results using a small hand balancer or even a nail through the propeller boss. Flite Test has a great explanation and demonstration of the procedure on Youtube. You will also note that several of the more popular multi-rotor propellers are available in multiple colours. The idea is that the front 2 motors are fitted with (for example) red propellers, and the rear motors are fitted with a different colour. This assists the pilot with orientation - knowing which way the craft is pointing, and which way "forward" is - at a glance. You may wish to do this; it's quite effective, but having enough spare props that having one that's both the right direction (CW or CCW) AND the right colour can be expensive. There are other ways, such as different coloured arms on your frame, or the use of LEDs, which can achieve a similar result. Finally, there are many people using 3-bladed propellers in multi-rotor aircraft. The main reasons for this can be increased "traction" due to the greater surface area of the blades, improved balance since the blades are spread around the hub at 120 degrees rather than 180, and the reduced blade length (for equivalent thrust) giving better clearance to other equipment. In theory, 3-blade propellers create more drag and are less efficient than 2-bladed ones, but the difference is often small enough to be invisible. Feel free to give them a try if you like. Edited by klaw81 - 09/Sep/2013 at 11:49am

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 05/Feb/2013 at 1:45pm
	Battery When choosing a battery, the two main things to be concerned with are capacity and weight. On the face of it, it seems simple - a battery with a greater capacity will keep your aircraft in the air for longer. However, batteries with greater capacity are also heavier, which means your motors need to work harder to keep the aircraft in the air. You may end up getting a shorterflight time from a larger battery, if you're not careful. The method I used to decide which battery to use is relatively simple. My motor-choice rule of thumb is to have twice as much thrust as my aircraft weighs. Since the battery is the last main (heavy) component I'm selecting, I now have a pretty good idea how much thrust I will have, and how much weight I can afford to add. So I simply add up the weight of all my components and payload (minus the unknown battery) and calculate how much "spare" thrust I have to achieve the 2:1 thrust to weight ratio. I can then find a 3-cell battery of around that weight - easy. Be aware that 4 motors running at the same time can draw a lot of current. Ensure that your battery's C rating is sufficient to support 4 x your chosen ESC's maximum current. There's no way of knowing exactly how long your multi-rotor will stay in the air from a given size battery. The weight of the aircraft, the flying conditions, the type of motor, the size of propeller and the pilot's flying style are all factors which have an impact on battery life. As a starting point for your search, I'd suggest a 3S battery with a capacity of around 2700-3000mah. You may need to adjust that to suit your aircraft's weight and thrust. I personally recommend using Turnigy NanoTech batteries, because they have a good C rating and have excellent weight/capacity ratio. HobbyKing has a Battery Finder function you can use to help select a battery with the right capacity and weight. It's a very useful tool. As I mentioned in the motor selection, most hobby-grade multi-rotors use a 3-cell battery. I don't really know why this is - it just seems to be a good weight/cost/power compromise. I have successfully used a 4-cell battery on my own multi-rotor aircraft without problems - but I first had to check that my motors and ESCs could handle the extra current. I found that the aircraft was much more twitchy than when using the 3-cell battery for some reason - perhaps the control board was more sensitive with the higher voltage. Give it a try if you like - but be careful not to overload your components. Other electrical components There are a couple of other electrical-related items needed for a complete multi-rotor aircraft - these are explained in greater detail below. A power distribution board is often used to make connecting 4 sets of ESC wires together in a neat and orderly manner. Power distribution boards are usually a simple circuit board with 2 tracks, one for positive wires and one for negative wires. The circuit board generally has a number of solder pads, or sometimes plugs, which each of the ESC power wires can be connected to. A single additional connection point is provided for the main battery lead. Power boards are a great, cheap and lightweight way to keep your main wiring organised - but they are generally only useful up to a maximum of 80A or so. Beyond that, cabling is required instead - the circuit boards cannot cope with high currents. HobbyKing sell a couple of different types, you can choose whatever suits your application or even make your own. Also, note that many of the smaller quad frames have the power distribution pads built into the frame itself to save weight. A low battery alarm is another vital piece of equipment for any multi-rotor aircraft. This small item monitors your battery's voltage, and sounds an alarm when it drops below a certain amount. This alerts the pilot that a landing will soon be necessary to prevent a loss of power and the inevitable damage it will cause. You will need a LiPo battery charger, if you don't already have one. You don't need anything fancy, so long as it can charge a 3S battery it will probably be fine. HobbyKing's offerings around the $25-30 mark are great value, and they're pretty much identical inside - my Accucel-6 has been going well for years now. Bear in mind that many of the cheaper chargers are designed to be powered by a car battery and can't be plugged into a wall socket without an external AC power supply brick (like a laptop has). Radio transmitter and receiver Having a multi-rotor isn't much fun if you can't control it. You're going to need to have wireless communication with your aircraft to steer it in the right directions. If you already have a 4-channel (or more) radio, all you will need for your new multi-rotor is a spare 4-channel (or more) receiver, preferably a compact lightweight one. If you have additional channels, you may wish to control additional functions on the control board, such as auto-pilot or RTH if your board supports this, or to trigger lights, operate a camera or toggle a bomb drop. Note: In addition to the receiver itself, you will also need a set of 4 male-male servo leads about 10cm long, to connect your receiver to your control board. For beginners who have no RC equipment: There's a massive range of RC radios available, starting at $30 and going into the thousands. I could write a whole new thread about the various choices. Almost any radio will be fine to pilot your multi-rotor craft, so your choice of radio will probably be dictated by budget. I would strongly recommend (at very least) a basic 2.4Ghz programmable radio, capable of dual rates and exponential curves - this will allow you to increase or decrease the sensitivity of the aircraft to your commands. Trust me, you'll be glad to have these functions. Besides, you're likely to want to fly other aircraft too, and having a programmable radio will usually allow you to use it with several different aircraft. My recommendation: the Turnigy 9X and 9X-R sold by HobbyKing are excellent radios. For $50, you won't find better value radio equipment anywhere. Bear in mind that both radios need a bit of extra equipment to get the most out of them - neither come with batteries and the 9X-R doesn't have an RF module or receiver. Edited by klaw81 - 18/Feb/2013 at 2:17pm

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 05/Feb/2013 at 1:58pm
	<edit August 2014> The world of multi-rotor aircraft moves rather quickly these days - newly developed parts are being released regularly, and older designs are being updated with additional features. There's no chance that I will be able to keep up with changes on HobbyKing's products, or their pricing. Please treat this list as a guide to assist you with your own part selection. THE PARTS LIST Below is a list of parts for a basic quadcopter. This aircraft will be suitable for beginners who have never flown a multi-rotor aircraft before. It will be relatively cheap, stable, reasonably robust, and able to easily carry a payload such as a small video camera. You shouldn't need any specialist tools to complete this build. A basic set of screwdrivers, and some pliers should be all that's needed to get the kit assembled. <edit: a tiny bit of soldering will be needed for the BEC and low battery alarm - I can't find a way to avoid this> But first, a disclaimer: This list is something I have put together from my own knowledge and experience, to assist you with your pursuit of this hobby. I have not personally built this exact machine. I cannot personally guarantee that you will be able make it all work, nor can I guarantee that you will have the necessary skills to fly it properly. You will need to follow the instructions supplied with the equipment and be prepared to do your own research to ensure it's correctly used. You will need to have patience and perseverance, and possess problem-solving skills and common sense. In short - use your brain, and don't come crying to me if it doesn't work. This list is by no means the only possible combination of parts you can use. There are many other parts that you could use instead, which could work equally well. I have chosen the parts listed below based on price, weight, quality and simplicity. Feel free to choose other products, or even other sources of products. All of the parts are sourced from HobbyKing, because that's the website we're on and that's where I shop for this stuff. Each component has its retail price (correct at time of writing, and subject to change) and an estimated or actual weight shown. I have also indicated where multiples of the same component are required, or where additional accessories are needed. A summary of prices and weights is provided at the bottom. Control board $30 (21g) As recommended in my post above, the KK 2.0 flight controller board is an excellent board at a very affordable price. It will provide sufficient stability for a beginner and is easily configured and tuned via the screen and buttons. Frame $14 (~400g) The X525 Glass Fiber Frame is big enough to be stable and easy to see, and tough enough to cope with the odd rough landing. It's cheap enough to replace parts or even the whole frame if it breaks, and it can fold the arms in to make it easier to transport. At $14 it's a total bargain. Motors $17 each inc. accessories, 4 required (260g total) I have no doubt that people will disagree with my choice of motor, regardless of what I recommend. Everyone's needs vary, based on what they want to do. For this application, I'm going for something that's lightweight, reasonably affordable, doesn't draw too much current, and gives me a little headroom for some payload running a 3-cell battery. I reckon the NTM 28-30 800kv motor is a great choice - heaps of grunt for this application, weighs only 65 grams, can handle higher voltage (3S to 6S) if needed and it's a quality product. There's not a lot of relevant thrust info available on the product page, but it should be good for at least 800 grams of thrust at around 15 amps. It should be noted that these motors don't come with a mounting cross or anything, just the bare motor. You need to buy these parts separately from here Speed controllers $8 each, 4 required (100g total) Since we're on a budget build, I'd recommend the MultiStar 20A opto ESC. These are designed for multi-rotor applications, and come with all connections pre-soldered for ease of use. The "opto" part of this ESC means that there's no integrated BEC in the ESC to power anciliary devices, as is common in small ESCs. You will need a separate BEC like this one ($4, 8g) to power your receiver and control board. Update: for those with a bit of extra cash to spend, I strongly recommend upgrading ESCs to the SimonK-equipped Afro 20A ESCs. The upgrade will cost you an extra $18 (they are $12.50 each, and you need 4) but the increase in stability and responsiveness is worth it. The plugs are pre-soldered and compatible with the rest of the parts list. Note that the separate BEC required above is NOT required for the Afro ESCs, there's an integrated BEC in each ESC. Propellers $7 for 2 packs (60g) For the NTM motors I've chosen, a 10-11" prop with a pitch of 4-5" is about right. These ones are available in several colours if that excites you. I suggest you get at least 2 packs, since you're likely to break several props while learning. You might want to experiment with slightly larger props (up to about 11x5 max) later on, but these should get you started. Battery $26 (263g) The NanoTech 3S 3300mah is a good compromise of weight, price, discharge rate and capacity. I anticipate flight times of over 10 minutes. You might be able to move to a 4-cell battery later on, using all of the above equipment. This will give you a greater payload capacity, but you will need to monitor your ESC temperatures. Power distribution $4 (47g) With 4 motors drawing a maximum of 20A each, this aircraft is already almost on the limit of what a standard PCB power distribution board can handle. For the sake of future upgrades and simplicity, I'd recommend the use of a power breakout cable instead - this should just plug directly into the battery and ESCs, no soldering required. Other bits and pieces Mounting foam $2 (1g) Since the flight control board is sensitive to vibrations, it's a good idea to mount it on some vibration-reducing foam. These ones are very cheap. Battery alarm $2 (7g) This little device warns the pilot, using a siren and flashing lights, when the aircraft's battery voltage is getting dangerously low. This give the pilot time to land safely, before the motors cut out. It plugs directly into the battery's balance lead, so there's no need for extra wiring. Battery strap $2 (5g) This clever velcro-style strap will allow you to hold your battery firmly underneath your quad frame. Receiver leads $5 (28g) These short leads are needed to connect your radio receiver to your control board. Item Price Weight Control board $30 21g Frame $14 400g Motors $68 260g ESCs $32 100g BEC $ 4 8g Props $ 7 60g Breakout cable $ 4 47g Mounting foam $ 2 1g Battery alarm $ 2 7g Battery strap $ 2 5g Receiver leads $ 5 28g Totals $174 937g If we allow another 50 grams for screws, prop adaptors and so on, the whole aircraft has a flying weight of about 1kg and a thrust to weight ratio of about 3 to 1. This should mean long flight times, responsive handling and no over-stressed components. It should be able to comfortably carry up to 500 grams of additional weight - an extra battery, a video camera and FPV gear, or whatever else you can dream up. Please note you will need a LiPo battery charger, a suitable radio transmitter and a light-weight receiver. These are likely to cost an additional $100 or so, including postage. See the post above for details of my recommendations for these items. Edited by klaw81 - 27/Aug/2014 at 8:04am

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 05/Feb/2013 at 2:08pm
	Some simple tips for building and setting up your new quadcopter: 1. Balance your props! The clever electronics in your control board that keep your aircraft controllable can be very easily upset by vibrations in the airframe. If your props aren't balanced (one blade is slightly heavier than the other) then they will create lots of vibration when they are spinning. Vibration can also damage your motors and rattle your screws loose. Balancing propellers is a simple procedure and only takes a couple of minutes. Although a good prop balancer can do a more precise job and only costs $15 or so, you can balance a prop using a simple thin metal shaft (eg a nail) and get a decent result. FliteTest's Youtube channel has an excellent explanation of the prop balancing procedure. It's an easy way of making your aircraft fly better, and reduces the need for constantly re-tightening your screws and bolts. Set aside 20 minutes and balance every prop in your collection, it's well worth your time. For FPV, where vibrations can turn your video feed to jelly, some pilots also dynamically balance each motor and prop as a whole. This is a little more complex, but might be worthwhile if you're having trouble with vibrations. 2. Help with orientation When it's in the air, you may very quickly find yourself unsure about which way your aircraft is facing. This makes it difficult to provide the correct control inputs, to avoid an object or counter a drift. There are a number of simple methods to make it easy to recognise the orientation of your aircraft. Some frames come with different coloured arms, right out of the box. For instance, the front arms (for an X format quadcopter) might be white while the others are red or black. If your arms are all the same colour, a quick coat of spray paint, or a few wraps of coloured tape in a contrasting colour can quickly fix this. Many pilots use different coloured propellers, which appear as coloured circles when the props are spinning. This is a reasonably effective method of quickly establishing orientation. If you don't want to buy coloured props, it's very easy to add a little colour to black props with spray paint or a paint pen. Don't forget to check the balance afterwards though. Finally, you can use LED lights to create a colour scheme for orientation. For instance, you could have a forward-facing white LED, a strip of red LEDs on the right arm and a strip of green LEDs on the left arm. LEDs are light, cheap, and use very little power so they're ideal for making a cool colour scheme. 3. Remove your props when checking things This is a simple safety precaution that can save you some pain. A large propeller can easily open a large wound on your hand if you are unlucky or foolish enough to get in the way. Your quadcopter has 4 propellers , so there's a large "danger zone" and a very real risk of injury. This is especially true during the setup stage when you're constantly adjusting settings on the control board, messing around with wiring and so on. If you're doing any configuration work where you're operating the motors but don't intend to actually fly, it's a good idea to simply remove your propellers. 4. Calibrate your ESCs This is a very important step - don't skip it! The ESCs on your multi-rotor aircraft might all look the same, but they may not respond to the control board in exactly the same way. To ensure that each of the ESCs will react in exactly the same way to a given throttle setting, it's vital to "teach" them the limits of the control signal. There are a few different methods of doing this, depending on your ESC and control board, but here's a method that's pretty much universal. I have assumed that your aircraft is fully assembled, with all motors etc connected, and that your radio is programmed. 1. Ensure your aircraft battery is disconnected. Remove your propellers for safety (see Step 3 above). 2. Determine which channel on your receiver is your throttle channel. It may help to follow each of the wires to the control board, where the channels are marked. 3. Remove all of the control cables from your receiver. You can leave them plugged into the control board at the other end. You might want to label each cable before removing them, so you can easily plug them in again later. 4. Remove one of the ESC control cables from the control board, and plug it directly into the throttle channel on your receiver. 5. If you have a stand-alone BEC powering your control board and receiver, remove it from the control board and plug it directly into the receiver (any spare channel, not the throttle). 6. Turn on your radio, and move the throttle stick to 100% (full throttle). 7. Connect your aircraft battery. Don't worry, the aircraft won't fly away on you. 8. As soon as the battery is connected, a light on your receiver should turn on. If the light doesn't turn on, or starts blinking, you need to ensure that your receiver is being powered and that it's bound to your transmitter. 9. Shortly after the battery is connected, your ESC should make a short start-up tone, and then a long beep. Once you hear the long beep, return the throttle stick on your radio to zero. 10. Your ESC should make a confirmation beep, and then play the startup tone again. Your ESC is now calibrated. Unplug the battery, and plug the ESC's control wire back into its previous location on the control board. 11. Repeat steps 4-10 for each ESC, until all are calibrated. 12. Plug your receiver's control wires (and BEC if applicable) back into the control board. For those who may have a little difficulty setting up your KK2 board, there's a number of excellent guides available on Youtube and various websites. Here's a good one: http://www.rcproreviews.com/kk2-0-flight-controller-setup-and-settings/ Edited by klaw81 - 09/Sep/2013 at 12:03pm

PierHenri62 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (0) USERID: 244830 HobbyKing aficionado Joined: 12/May/2010 Online Status: Offline Posts: 262	Quote Reply Posted: 05/Feb/2013 at 3:54pm
	Great job, Klaw81. Pierre

Sooty Members Profile Send Private Message Find Members Posts Add to Buddy List N/A (N/A) USERID: 0 Hobbyking Addict Joined: 10/Mar/2009 Location: Christchurch NZ Online Status: Offline Posts: 6044	Quote Reply Posted: 06/Feb/2013 at 10:33am
	from me too. Suggestion for avoiding frustration - when buying motors for a multi-rotor purchase a couple of spares with the initial order. If you strike a motor that is faulty or will not synchronise correctly with the other motors, then there is a real chance that when you try to re-order replacements they will be out of stock for some considerable time. From personal experience there is a fair chance that you will strike one motor in a batch that works fine on its own but will not start and stop in unison with the others.
	Sometimes when I reflect back on all the beer I drink I feel ashamed. Then I look into the glass and think about the workers in the brewery and all of their hopes & dreams.

klaw81 Members Profile Send Private Message Find Members Posts Add to Buddy List Platinum (AU) USERID: 605444 Hobbyking Addict Joined: 21/Sep/2010 Location: Queensland Online Status: Offline Posts: 579	Quote Reply Posted: 18/Feb/2013 at 11:43am
	Thanks for the suggestion Sooty. I will add in a few comments at the end of the posts; yours is a good one, although it's not an issue I've encountered personally. I am working on a parts list for a basic budget quad, I will post it up in the next few days. Also, bump back to the top where noobs will see the thread..... :)