Easy To Follow Guide On How To Setup Your Servos

After the long task of assembling your RC helicopter from the countless little plastic bags of nuts and bolts, there still remains the often daunting task of setting up your RC helicopter.

That's where this guide comes in handy...

This quick guide shows you how to setup the servos and makes sure the servos are working correctly.

Also, this guide is designed for beginners and novice nitro or electric RC helicopter enthusiasts that have a collective pitch (CP) system.

Note: On electric helicopters, you have to approach the setup a diferrent way. Please use caution and ask members for tips in the forum.

By the way, this guide uses a nitro RC helicopter as an example but this doesn't necessarily mean this guide is designed for such. The difference might be the "servo throttle" setup which electric helicopters don't have.

You might be asking yourself, why should I worry about the servos being adjusted correctly?

Well, it might be wishful thinking to just open the heli from the box then dash through the sky but I'm afraid it's not that easy. Since you are just starting to fly RC helicopters you need your heli to fly as steady as possible in order to succeed in hovering, flying, etc.

Also, by properly adjusting your servos you will extend their life.

One more thing I wanted to mention...

If you can get someone to check all the settings and perform a test flight on your RC helicopter, then this is highly recommended. But it is possible to learn on your own.

Here are some of the benefits of properly adjusted servos:

* Accurate flying

* Extend life of servos

* Flying success

In this guide, I will be using a Futaba 9c (Radio) and a collective pitch system (CP) nitro RC helicopter.

In this section we'll be looking at the swash plate.

You need to make sure the servos are moving the swash plate in the right direction and that the linkage rods are connected to the servos as close to a 90 degree angle as possible.

 

REMEMBER: The reference starting point for all adjustments is CENTER STICK.

 

Step # ONE - Turn on the transmitter (Tx) and the receiver (Rx). The servos should now move to their center positions.

Step # TWO - Set transmitter Rudder Trim (the little button that moves left or right) controls to center position, and set the throttle/collective joystick to the middle position.

Also, leave the Throttle Trim (the little button that moves up and down) fully down at this stage.

  Before we start on the cyclic servo, here's something you should know...

Cyclic servo

Definitions:
Cyclic pitch is the individual angling of the blades on each revolution of the rotor. This affects the moves of the RC helicopter, moving the nose upward or downward or rolling the craft from side to side.

Aileron:
  this is really an airplane term, but is easier to say than "cyclic roll." Ailerons are what make an RC helicopter go left or right

Step # THREE - With the tail pointing towards you, move the left/right cyclic (aileron) control to the left. The swash plate should tip to the left.

                       

Here's a Rear View	Here's a Side View

Step # FOUR - Next, move the left/right cyclic (aileron) control stick to the right. The swash plate should tip to the right.

                     

Here's a Rear View	Here's a Side View

Note: If the swash plate moves in the opposite direction, change the direction of the servo, see "reversing" under your radio's computer setup under "servos".

  Step # FIVE - Move the front/back cyclic (elevator) control stick forward. The swash plate should move to the front of the helicopter.

Reverse the channel if it goes the wrong way.

                     

Here's a Rear View	Here's a Side View

Step # Six - Move the front/back cyclic (elevator) control stick down. The swash plate should move to the back/tail of the helicopter.

Reverse the channel if it goes the wrong way.

                     

Here's a Rear View	Here's a Side View

Step # Seven- Let the cyclic joystick rest in its center position (center stick), and check both the aileron servo linkages, and elevator servo linkages, for the following...

a. The servo arm should have an angle of roughly 90 degrees with the servo linkage rod. If it doesn't, undo the servo horn (plastic star circle) from the servo, rotate it and check again.

REMEMBER: The reference throttle point for this adjustment is CENTER STICK.

b. The swash plate should be level when the stick is in the CENTER position. If it's not leveled, adjust the elevator servo linkage to get it level.

                            

Collective (Pitch) Servo Initial Setup

In this section we need to make sure the blades are moving in the proper direction. We'll play around with the throttle/collective stick, which is the left control stick on your radio.

Step # Eight - Move the throttle/collective joystick from half/center to its bottom position.

Observe the rotor blade holders, they should tip up... this means "negative pitch" on the main rotor blades. Negative pitch will make your RC helicopter come down.

Next, move the throttle/collective to the top position.

Notice how the blades holder points down...This means "positive pitch" on the main rotor blades. Positive pitch will make your RC helicopter go up.

Note: If the direction is wrong, reverse the pitch channel. (Channel 6).

                                   

Step # Nine - At half throttle/collective stick position, the linkage rod for the pitch should be around a 90 degree angle to the servo horn. If not, rotate the servo horn (plastic star circle) and re-check.

Collective (Pitch) Servo Initial Setup

In this section we will discuss on how to setup the tail rotor. We need to make sure the tail grips are moving in the proper direction.

Note: Most RC helicopters have a "clockwise rotating main rotor", as a result the model will try to rotate anti-clockwise or nose to the left if it weren't for the tail rotor.

The tail rotor helps the RC helicopter compensate the heli either clockwise or counter-clockwise depending on the main rotor rotation.

Step # Ten - Return the throttle to center position. Adjust the rudder servo horn position on the servo steel balls such that it makes the 90 degree angle we talked about with the rudder linkage rod.

Adjust the linkage rod that controls the pitch of the tail rotor to a position that gives alignment/pitch to the blades. Make sure we give the tail rotor some pitch. Here are some examples:

1. For a clockwise main rotor rotation, adjust the tail rotor so that the one tail rotor grip   (top grip) points slightly to the right; this will compensate the heli to the RIGHT.

 

2. For a counter-clockwise main rotor rotation, adjust the tail rotor so that the one tail rotor grip (top grip) points to the LEFT position. This will compensate the heli to the LEFT.

Note: The tail rotor blades will now have some pitch. This is the amount of pitch needed to offset the torque of the motor at hover.

In order to prevent the RC helicopter from turning to the left we need some kind of pitch on the tail rotor, this will makes the heli move to the RIGHT which straightens out the RC helicopter.

Step # Eleven - Move the rudder control to the RIGHT. The pitch on the tail rotor blades should INCREASE.

                     

 

Step # Twelve - From center position, move the rudder control to the LEFT, the pitch on the tail rotors should DECREASE, and pass through zero pitch (no pitch/angle on the blades), and in fact will end up a little the other way.

                     

Note: If the direction is wrong, the channel will need to be reversed.    

Throttle Servo Initial Setup (Nitro Engine)

This section only applies to RC helicopter that have a nitro engine in place. We'll see how the linkage from the servo to the throttle should look.

Step # Thirteen - As before, at half throttle position, the servo arm should be close to a 90 degree angle as possible to the linkage rod, which should be close to a 90 degree angle as possible to the carburetor lever arm.

These angles are only approximate, as some linkage rods have to be bent to clear the muffler or manifold.

REMEMBER: The reference starting point for this adjustment is CENTER STICK.

Warning: You need to know which way the carburetor arm moves to close or open, in other words, increase or decrease the throttle. You want to make sure when you position the throttle/collective stick fully down that engine will idle, instead of increasing to high speeds.

Step # Fourteen - Inspect the engine before assembling the engine to the model. For OS engine, the carburetor arm rotates Clockwise to shut off, and Anti-clockwise to open.

On an OS engine, check that the carburetor rotates clockwise when the throttle is reduced to zero stick (Throttle/collective stick all the way down)

Note: In most radios, you have the feature where it will let you adjust the end point settings. The end point will adjust the total travel the servos will give.

For example, if you increase the throttle/collective stick to the fully-up position resulting in 100% of travel. But if you needed to, you can adjust the end point to only give 80% of travel at the fully-up position. You can accomplish this by lowering the end point for the fully-up position to 80% on your radio.

Step # Fifteen - The throttle channel on the Tx may need ATV adjusting, better known as END POINT

With the throttle/collective trim at zero (i.e. fully down) and the joystick also fully down:

1. End Point the throttle channel (channel 3) so you can see the linkage rod trying to very gently move the carburetor lever arm to the decrease/ fully off position.

2. Now you'll know that you can shut down the engine from the Tx with the throttle stick down.

Now, with full collective/throttle stick fully up:

1. End Point (channel 3) so that you can see the linkage rod trying to very gently move the carburetor lever arm to the increase/fully on position.

2. Now you'll know that you have full power when the throttle stick is fully up.

Note: If you notice that the servos are making a binding noise (loud buzz noise) that means the servos are working too hard. If the servos work to hard, they will consume more battery energy and even lower the life of the servo. Try to relieve the binding by decreasing the end point.

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Congratulations!

By completing this easy-to-follow guide, you have learned how to setup your servos to the widely recommended use. Best of all, you now know the direction the servos need to move in. As a result to the proper setup, you will greatly decrease your chances of getting frustrated with the setup process.

You have specifically learned how to:

 
• Set a 90 degree angle  
 
• Correct swash operation  
 
• Throttle setup  

Please let me know what you thought about this guide, I'd love to hear from you.