[Toro]

THE DEVIL'S MACHINE? HA ! HARDLY ! The basics of the basic....

Many of us fixed wing guys, or perhaps the complete noob has at one time or another wondered what it would be like to try a helicopter at some point. About 4 years ago I took the plunge, and since 2006 have been focusing on rotorcraft solely. In this series of articles I will take you through some of the basics of build, electronics install, basic flight, and tuning for 3D. I will prove to you that once understood, these things are pretty easy to set up, and even easier to fly. Ever since I can remember being in R/C there has been a stigma associated with said rotary wing aircraft, and the difficulty in flying and operating them. I will prove this wrong. I will be using the ALIGN 600N which is probably the hottest 50 size helicopter on the market to date. It is an outstanding flyer that was designed by a friend of ours; you may know him as JASON KRAUSE. The heli was put through the ringer by the designer himself, Alan Szabo Jr. and Danny Szabo. The heli has proved very airworthy and is a platform to not only begin your heli modeling with, but will take you through the highest ranks of 3D. So lets get started.
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This is how a heli comes packaged. It is more similar to an R/C car in its assembly methods, and if you can follow directions, and read diagrams and schematics, you can build one of these. Every package is numbered for your ease of locating certain parts, and the instructions include a bag number for your parts to be used in that section of construction. At first you may find all the nuts, screws, and bolts intimidating, but after settling into construction, you will find it easy to recognize what you need. I find a muffin tin works excellent for organizing parts, and screws. The build of this chopper starts with the construction of the main rotor head and mast section.
You can basically take the heli and break it into 3 parts. First there is the main frame of the heli. The main frame will include the engine, and pipe, the fuel tank, or battery. The electronics group including gyro, receiver servos, and power supply, and finally it will also include your main gearing, and tail drive system. The tail drive system on the 600N comes in 2 different versions, either the belt driven system, or a torque tube system which is directly gear driven through a power output shaft. For the beginner I would recommend the belt driven system, as this will allow a little give should you strike the tail rotor on the ground.
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Here is a picture of a completely naked main frame. This little piece of art is what makes this whole thing tie in together.
The second part of our helicopter is the tail group. This includes the tail boom, the boom supports, the tail case, the fins, and of course the tail rotor. This grouping is typically exposed to the dirt and dust, and typically will sustain damage from a main rotor strike should you have a crash. Just like full scale, the tail rotor can fail, and cause a crash so it is imperative to make sure that when you construct this part of the heli you take great care in getting it right and inspect this part frequently, as this will bring your bird down real fast when your learning. The tail is an area where vibration is magnified tremendously. Imagine shaking a fishing pole in your hand. A little movement at the base is magnified at the tip 10 fold. It is mandatory that loc-tite be used on all metal-to-metal parts in the entire construction of these little machines. Remember as the saying goes, a helicopter is 1000 moving parts all trying to destroy each other. Loc tite is your friend here. This area of the helicopter is what controls the YAW of the helicopter. This is accomplished through inputs from your RUDDER channel, and is also automatically done through gyro inputs to your rudder servo. YAW is accomplished through pitch changes delivered to the tail rotor. YAW speed is directly proportional to pitch. IE the more you pitch you give it the faster the heli pirouettes. This is one area on a heli that can be the most frustrating to setup for a newer chopper pilot. You’ll see more people seeking help for tail troubles at the LHS than any other problem. A gyro is a little tough to understand how to set up but familiarity brings comfort. Once you understand what gain is (gyro sensitivity), mechanical gain (setting up the tail for a neutral hold in non-heading hold mode), and also setting up pirouetting speed, you’ll have about 90% of the battle done with setup. The 600N’s tail is solid and powerful. Setup is straight forward and is easily accomplished with this little gem of a heli. I like to try and mount all my servos under my canopy to give some protection. Align has done this for the rudder servo, and set up a slick bell crank system to prevent couplers, or bends in the control rods. Very slick, and a nice clean setup. (PICTURE) We will discuss tail setup further in another article.
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Lastly in the 3 parts approach is the main rotor head. This is where all those stick inputs on the transmitter make the magic happen. The main rotor head is what really could throw a new guy for a loop. The whole thing by its very nature looks super intimidating. With all those links, and moving parts, who would believe that you don’t need to be an aerodynamics/mechanical engineer to figure this stuff out? Some terms you may hear while building the main head are swash plate, washout lever, blade grip, elevator control, fly bar, paddles, hub, feathering shaft, dampers, and a few others. Don’t let this get to you, as you only need be able, again, to follow instructions and schematics. Essentially this where 3 of the main helicopters flight aspects are controlled. Your collective, your roll cyclic, and your pitch cyclic are all coming from this main part. All of this is controlled from a sliding plate known as the swash plate. Depending on what your swash is doing is what your helicopter is doing. If you think of your swash plate as a picture of your rotor disc, this is what the helicopter will be doing. So when you set up your heli, if you stand behind it, and move your stick to the right the swash plate should lean to the right, stick back, the front of the swash should move up and the back down. This is the easiest way to make sure your control inputs are right. If any of these are wrong, you will have a servo reversal situation, and you know what happens with those. All 4 inputs of Left, Right, Up, Down should reflect directly to the swash when standing behind the heli.



here are a few of the items discussed, and listed. The biggest recommendation when building this part is to make sure you have a digital caliper to assist with measuring your linkage distances. A small tool that is used to make your linkages is sold commercially, but I find that when using that you more than likely will confirm your tolerances with your calipers. When you make more than one linkage of the same size, 1 mm off can change the whole way the heli trims out on the first flight.


If you intend to continue in this hobby, whether it be for a fixed wing, or rotary, I highly recommend a really good set of screwdrivers, allen wrenches, small sockets (metric) and nut drivers. There are many a company out there that has them available. Whatever you decide to purchase as far as tools go, make sure they are the highest quality that you can buy for the money.


This is the first of a series of articles I will be writing on building, setting up, and flying helis. Stay tuned for more goodies in the weeks to come as we cover ELECTRONICS install, TUNING, and FLYING your heli... FG ~