link flybar lama v4

[binaki]

Hi
What is the relationship of the flybar to the upper blades by way of the length of the bell link. If you lengthen the link or shorten it, the flybar and the top blades are not parallel. Either in a forward direction or back...does that make sense?
I guess parallel is correct but is their a relationship to how the heli flies if you change the lenth of the link? I think i moved mine when the flybar popped off. Is their a preferred setting?
regards

[4n6days]

That link controlls your blade tracking. For optimum performance you want both clades tracking in exactly the same plane. Put a little white out or silver sharpie on the tip of one of the blades. Fly it up to eye level and see if one blade is riding higher than the other. Adjust the link accordingly.

[mnwizard]

Sorry, but the flybar on the V4 has nothing to do with blade tracking.

The flybar is solely to stabilize the heli.

It acts like a gyroscope.

Picture the V4 in a stable hover. The lower blades spinning are one disk.

The upper blades spinning are another disk, completely independant of the lower disk. There is no control linkage between the upper disk and the lower disk.

Finally, the spinning flybar makes a third disk. The flybar disk is connected to the upper blade disk by the single control linkage between the two.

In a stable hover, all three of the disks, lower blades, upper blades and flybar are spinning parallel to each other.

All cyclic input is through the lower blades. The swash plate can be tipped in any direct by the control arms linked to the servos. When the swash plate is tipped, the the control arms from the swash plate to the lower blades tilt the disk comprised of the spinning lower blades in the same direction that the swash is tilted.

The swash plate on the V4 does NOT change the pitch of the lower blades, it only tilts the spinning disk of the lower blades in the direction determined by the input from the servos. The swash and servos have no physical control link to the upper blade disk and they have no physical control link to the flybar disk.

We'll use forward flight as an example, but movement of the heli in any direction works the same way.

From a stable hover, with all three disks parallel to each other, the cyclic stick is moved forward causing the elevater servo to tilt the lower blade disk toward the front of the heli.

Tilting the lower blade disk forward causes the heli to tilt forward, and the heli begins to move in the direction that the lower blade disk is tilted.

The inertia of the flybar disk, which has no control linkage connection to the lower blade disk, causes the flybar disk to resist movement and it remains parallel to the ground, and the linkage from the flybar to the upper blades causes the upper blade disk to remain parallel to the flybar disk. So both the flybar disk and the upper blade disk remain parallel to the ground.

Since the lower blade disk is tilted forward, and the upper blade disk is not, the upper blade disk resists the forward movement of the heli.

In short, the flybar, acting much like a gyroscope, resists movement and because it's connected to the upper blade disk, the upper blade disk is always acting to counter movement of the lower blade disk.

It gets more complex when actual horizontal and vertical movement of the heli is involved, but it's the same principle. The flybar and upper blades act to counter any movement of the heli. It is this countering of movement that makes the coaxials so stable.

So, the link between the flybar and the upper blades should be adjusted so that when the flybar is parallel to the ground (technically the flybar should be at an exact 90 degree angle to the outer shaft), the upper blade holder is parallel to the flybar.

If the upper blades are not parallel to the flybar when the flybar is level, the heli will be less stable. This is a common cause for TBE.

Long answer I know, but it's difficult to explain in a short answer.

Finally, there is no tracking adjustment on the V4. The method given by Esky to correct blade tracking is to hold both ends of the low blade and twist the blade it's self , thus warping it to put more pitch in it. I've never had to do this.

[binaki]

OK,I try that and then tell you how I was
thanks

[JW_from_OZ]

Hello, I realize that this topic is 5 years old, but still very, very valuable. Jack is absolutely right! The fly-bar link on the ESKY Lama V4 has nothing to do with A-blades (Top blades) tracking. I set the link length so that the flybar settles in a perfect horizontal position when the blades stop after having revved them up to half throttle in a stationary position on a level bench. Revving them up first ensures that the blades are fully extended.
The tracking of the blades is adjusted as per the manual as Jack pointed out.
If still no luck, consider a new set of blades (even new ones are not necessarily matched) and don’t mix matched sets. Next suspect could be the A-blade grips and centre hub (the bit that sits on the top of the main shat that holds the A-blade grips.
Happy flying.
JW_from_OZ

[dayshaddow]

mad i havnt owned a lama for many years i was bord so poped in to see if my old lama forum was still active and there is still life yay who knows one day i may pull the trigger and get a new lama v3(my fav i have to say) a great way to get into this hobby.guess most are starting with msrx/align100's these days..off to ebay to have a look for a lama