Two links vs One Link on Elevator control rod

[awr]

My heli started out as a Raptor 30 V2 and I installed the 30-50 V2 conversion kit.

I'm trying to eliminate as much slop as possible in the head and noticed if I twist the flybar with the
flybar perpendicular to the frame (i.e. main blades pointing front and rear), I can move the leading
edge of the flybar paddle up and down at least 2-3mm, which seems unacceptable to my mind.

I traced the source of the most slop to the joint where the link from the elevator meets the link from
the servo at the point where the pitch arm hinge pin is located.

I've got the full bearing kit installed, and I epoxied the inserts that go around the screws onto the
screws to eliminate play between the screw and the inside bearing race. That reduced some of
the play, but there's still some there.

My question is, why did they include that joint for the elevator control instead of running just one
control rod from the elevator servo to the elevator control arm?

I'm guessing it was to minimize interaction when the pitch arm is going up and down, but I measured
the distance between the ball link on the elevator control arm and the ball link on the elevator servo
(with no links attached), going through the full range of motion (both servo, pitch arm, and elevator
control arm) and there was no change in the distance between the two points.

What problems are created if I make a single link between the elevator servo and the elevator control arm?

I apologize if this question has been asked before.

Wayne
Calgary, Alberta, Canada

[Mike SVOR]

http://www.heliproz.com/prodinfo.asp?number=804090
this will stop the slop in the swash plate

are you talking about lose or sloppy flybar control arms?

[awr]

If I do the same test with the flybar paddles parrallel to the frame, I don't have any movement in the flybar (i.e. when I grip the flybar paddles and twist them up and down,
they don't move).

If I turn the flybar 90 degrees so that the flybar is perpendicular to the frame, I have slop; meaning when I twist the flybar paddles, I can move them up and down at least 2-3 degrees. That must translate into an unstable hover.

Has anyone tried the direct single link with success, or is it a bad idea?

Wayne

[Mike SVOR]

mine clicks a little bit. not anywhere near 3 degrees though. my servo adds to the slop and it's compounded by the time it gets to the flybar.

is there any way you can get a video of what yours is doing?

[awr]

I'll try but I'm a bit lacking in the technical department when it comes to uploading the
video.

Here's my point:

The T-Rex 450 XL HDE and CDE both use a single direct link between the elevator servo and the elevator control arm. The T-Rex XL HDE is a miniature version of the Raptor with the exception that it has an under-slung flybar.

I haven't heard of any negative interaction on the HDE version. Since it uses a pitch arm
that's identical in design to the Raptor but only one link, why can't we eliminate the
two links and use just one?

Wayne