Tail_BoomStrike
Veteran
Location: Virginia Beach
| Experiment on this...... Then it might start to clear up the picture....
Remove the main blades, also the tail blades..... Disconnect the tail control rod from the tail servo.
Now try to spool up, but not too fast yet...... You will notice that the tail grip pitch arm will try to line up with or track the tail rotor plane of rotation, which is also the 0* position of the tail blades. The centrifetal force is slinging the pitch arm of the tail blade grip far as posible from the center of the circular plane of rotation. Move the tail slider so the pitch arm is away again from the plane of rotation, and let it go. The pitch arm will once again track the plane of rotation. Speed up the rotation and play with the tail slider control lever again..... You will notice that the amount of pressure you will feel will be much more the faster the speed of the rotation......
Now this explains why adding weight perpendicular to the pitch arm counteracts the centrifetal force acting on the pitch arm. The "chinese weight" being added will also have its own centrifetal force acting on it. Remember the pitch arm and the chinese weight rotates on the same axis. If the chinese weight will have more force than the pitch arm, as it tries to track the plane of rotation of the tail rotor, the grip will tend to angle towards 90* pitch instead of 0*.
Now if the centrifetal force between the two are balanced now matter what angle of these two opposing forces are from the plane of rotation. The "grip angle" will retain its orientation until you reposition it by moving the tail slider control lever, if this is a perfect world..... Now since none of these, pitch arm or chinese weight, could outdo each other to try to track the plane of rotation, changing the angle of the grip requires less force..... This translates to less torque required an the servo to change the pitch angle of the grip....
It might still be confusing. I know my explanation was still rather vague at its best..... But just try to read it through and it might sink in. You might then be able to explain it much better and concise....
Well I did this mod.... And I could well attest, having done so, I installed s3153 as well and my tail is rock solid as if I had the 9650 on..... But my version is the drill and tap. Well, I drilled and let the link ball screw do the tapping. So no extra spending for drill and tap set tool. It's aluminium, so the screw wouldn't have any problem tapping in........
Anyways there is another centrifetal force resulting from these weight added.... And that is actually a burden being shouldered by tail grip bearing.... That's why I elected to used the drill and tap method..... The further away these added weight from the center of the tail rotor plane of rotation, the faster it travels through space, resulting in greater centrifetal force produced, as the tail rotor rpm increases.......
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