After CNC Upgrade, Nose spins left 360 degrees

[wherndon]

Upgraded tail and head to purple CNC and now it spins constantly in a circle to the left while running up power sitting on the ground.
Please Help
Thanks

[tom dubya]

Is your drive belt for the tail installed correctly.

[wherndon]

I think so. Are you thinking the belt is twisted? How can I tell?

Also, when I follow the instructions on setting up the Belt the first step is to disconnect the motor which is in pin 3 on the receiver. When I unpug pin 3 nothing is powered on which will not let me get everything adjusted.

[sutty]

Just to chip in, you disconnect the motor by splitting the leads that go to it. Part way along you will see three bullet connectors, simply pull them apart. They are such a close fit it is not always clear that they are connectors at all. You only need to disconnect two of the three leads. This way the rest of the electronics remain powered.

The belt should have a quarter twist in it. You can check to see if it is going the right way by turning the main rotor clockwise, when viewed from above, and see if the tail rotor goes clockwise when viewed from the left side of the heli, i.e. the side on which the vertical stabiliser is mounted. Or anticlockwise when viewed from the right or tail rotor side of the heli. Note the leading edge of the blade should also go first when you do this.

I think it may also be possible to mount the blade grips for the tail rotors the wrong way around. It is certainly possible on the plastic tail, but I don't have a CNC tail to confirm. There is a thread on here or on Heliguy where someone had done just that. Maybe if you could post a photo of your tail it would be easier to say. Try comparing it to the manual, you should be able to see if you have the correct pitch on the blades.

Here is a photograph of mine, and a disconnected bullet connector, maybe this will help.
5466254663

If you have all this correct then maybe it is just a matter of adjustment, which is achieved by sliding the tail servo backwards and forwards along the tail boom. If it helps my servo body is about 9mm away from the body of the heli where the boom goes in, but I guess all are different to a certain degree.

Good luck.

[tom dubya]

Yep that was my thread on heli guy actaully lol. Its to late for me to look it up, i just got home from the casino and have discovered my wife may have a gambling problem Lol.
Let me know if you might think this is the problem and i'll look it up tomorrow.

[mnwizard]

Yep that was my thread on heli guy actaully lol. Its to late for me to look it up, i just got home from the casino and have discovered my wife may have a gambling problem Lol.
Let me know if you might think this is the problem and i'll look it up tomorrow.

Your post gave me a grin!

My wife used to like going to a casino a lttle south of the cities here. It's owned by one of the indian tribes.

A couple years ago one of my sons went to work as a copper for the tribal police department. Now she doesn't want our son to see her at the slots! :lol:

[wherndon]

You guys are awesome!!

The tail rotor was turning the wrong direction and the belt had more than a quarter twist. Pulled the tail boom off and corrected the belt twist and rotated the rotor grips.
.
The motor bullet electrical leads were next to impossible to get apart. I finally did and now my fingers are extremely sore...unreal how tight they were.

I will post a new thread on another issue so others can chip in.

[cobra314]

The belt was the wrong direction, but the blades were also backwards so it was in effect operating correctly, just in the opposite direction. We got it corrected by comparing Wayne's helo with mine. Got everything lined up, centered and then took it for a test flight. Man, that thing was scary! I had the stick all the way to the right, but couldn't keep the nose straight. Then when I would reduce power and bring it down the servo would give proper throw and the tail would spin in the opposite direction. We are figuring that it is the gyro. It was making some pretty bad crackling/popping noise. Wayne made another topic about that.

[kianhon]

Are you sure the tail has to turn clockwise when viewing from the left? Because my belt-cp tail is turning anti clockwise all this time. The main rotor is turning clockwise. This happen when I upgraded to Esky HH gyro (0704A).

I started this hobby 3 months ago, like many other newbies, I crashed so many times until I lost count. I could fix and fine tune every part of the heli even before I could hover. When I upgraded to HH gyro after the first 2 weeks of crashing, my heli just spinning like nuts (like a dog trying to bite his tail). I then accidently switched the direction of the belt and everything just magically became fine, head holds rock solid. Didn't notice the tail is turning the wrong direction until 1 month ago and it still is. But my head still lock at one direction

[Ber60]

Take a look at the first video in this sticky (http://www.helifreak.com/showthread.php?t=68592) , it shows the way it should spin

[Real_Sparky]

Kianhon.
If your tail spins the wrong way and you still have control of the tail that also means that your gyro is mounted upside down. If you are happy with it like this then leave it, if you want it right you need to reverse the direction of the tail while also reversing the gyro. It should be mounted with the writing reading upwards and the wires at the top.
Like this:
55093


Darin

[DierWolf]

Also if you upgraded to CNC tail box make sure you put the blade grips on the tail rotor on the right way...

[kianhon]

My Esky HH gyro mounted exactly the same way like Real_Sparky except it is on the right side (words still reading towards the sky). On my transmitter, my rudder is on reverse mode, head still go right when I give right stick movement. My blade grip is like everyone else belt-cp, facing right.

[DierWolf]

Blades facing right???

This is not what i am talking about... The blade grips themselves have to be installed correctly...

On Rotation (looking from right side of heli) the tail rotor should be turning Counterclockwise and the Ball ends on the Blade Grips should be spinning/pushing INTO the plastic link.

If they are facing the other way (pulling OUT of the plastic link) you will not get the proper pitch.

So 2 things you have to check

1. Rotation of the tail blade
2. Grips are on in the correct configuration.

I posted this picture once before which shows the correct way the grips should be installed... if its not like this it will NOT work.

http://www.buzzflyer.co.uk/images/belt-cp-cnc-tail/belt-cp-cnc-tail-12.jpg