Bbcorvette18
70cc twin V2
So this is my first time playing with a pull pull setup. I noticed today that I have quite a bit of play with the rudder before the servo moves. Obviously this is bad. My question is how much "slack" if any should there be?
Pull Pull Rudder slack/slop
- Thread starter Bbcorvette18
- Start date
Lojik
70cc twin V2
Its very difficult to describe the slackness needed on pull-pulls but for me if i had to describe how i tighten them I tighten them so that the midpoint between the servo and cross over point of the wires if squeezed together will not touch each other but will move at least half of the distance.
I was always told to make sure they are not so tight that you get a ping when flicked but not so loose that the rudder can move without the servo moving
I was always told to make sure they are not so tight that you get a ping when flicked but not so loose that the rudder can move without the servo moving
Bbcorvette18
70cc twin V2
This is after adjusting the rod ends more or less as far as I can go. It was at least twice as bad before adjusting.
[video=youtube_share;6uYP72dBfXE]http://youtu.be/6uYP72dBfXE[/video]
[video=youtube_share;6uYP72dBfXE]http://youtu.be/6uYP72dBfXE[/video]
Lojik
70cc twin V2
Its hard to tell what is happening to the servo end, can you take a vid servo end please, are you crossing over your wires??
that seems way too loose
have a look here:
http://www.desertaircraft.com.au/blog/?p=73
that seems way too loose
have a look here:
http://www.desertaircraft.com.au/blog/?p=73
Rolling.Circle
100cc
Sullivan makes a little turbuckle that you can use for adjusting. But, we've never used one because the standard setup usually allows for good adjustment. Get it pretty tight with the adjusting gear almost all the way out, use the double wrap method with the brass tubes you smash and glue with CA and then shrink, and then just tighten your hardware to taste. Usually do this with power on the servo(s).
We like the pull pull wires a little less tight than a guitar string would be. You won't have any sag in the wire when it's right. And, both sides should match in terms of tension (in a perfect world).
We like the pull pull wires a little less tight than a guitar string would be. You won't have any sag in the wire when it's right. And, both sides should match in terms of tension (in a perfect world).
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Bbcorvette18
70cc twin V2
The servo is fine. Thats all in the wires. They must of stretched a decent amount when I ripped the rudder off. I stopped putting pressure on the rudder when the servo started to hum and watched to make sure the arm wasn't moving.
The pull pull wires are not crossed over. But the geometry looks right.
The pull pull wires are not crossed over. But the geometry looks right.
Last edited by a moderator:
Rolling.Circle
100cc
I would have crossed them but I know what you mean. It looks right with them straight to the same side. Still works.
ЯК Attack
50cc
I think that unless you have the perfect geometry [mention=3387]Lojick[/mention] is talking about, there will be some slop on the side not being deflected when the rudder servo is turned. I may need a correction on that statement, though.
Other than that, there should be virtually no noticeable slop in the system. It shouldn't have any more free play than any other control surface on your plane.
The ultimate tell-tale of overly tightened pull-pull wires is a noisy rudder servo. It should be quiet when centered.
Other than that, there should be virtually no noticeable slop in the system. It shouldn't have any more free play than any other control surface on your plane.
The ultimate tell-tale of overly tightened pull-pull wires is a noisy rudder servo. It should be quiet when centered.
Bbcorvette18
70cc twin V2
Yea I think I'll try to cross them and see if that takes up any more the slack. I have a feeling I'll be getting some stuff from Aztech soon. While messing with this one of the motor bolts fell out of the firewall too LOL guess its telling me to go over everything