Tail Stops

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Russell
Posts: 22
Joined: Fri 26. Sep 2014 23:44:41

Ok what is the secret to getting tail stop even on both sides. I seem to have a soft CW stop and a solid CCW stop.
G380
BK tail servo.
Setup in rate mode.
Tail gains are set high and locked in and holds well.
Piro Comp is at 160.
Dynamic I have tried at 6-7.
Any suggestions on what to adjust.

thanks
Russell
kmaluo
Posts: 74
Joined: Wed 24. Jun 2015 21:36:20

Have you tried adjusting tail rudder limits? Increasing if possible on weak side. Sounds like the the Spirit can't adequately stop on the weak side because it can't get that extra millimeter it needs to stop the tail faster. If you're mechanically maxed out, then maybe slightly bigger tail blades are needed. You could also lower rudder speed to even things out as a LAST option.
ZeXx86
Site Admin
Posts: 12832
Joined: Mon 29. Apr 2013 16:06:44
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For Goblin helicopters it is needed to set Neutral position so that there is pitch of 3-4° when your servo arm is at 90°.

If it does not help, changing tail limits will solve the problem. You can decrease the limit on the side where overshoot (hard stop) is occuring. But this must be done carefully so your tail has still enough authority.
Mostly approx. 1mm will help.
Spirit System developer
Russell
Posts: 22
Joined: Fri 26. Sep 2014 23:44:41

Well I tried everything today.
Adjusting center to 0,4,9 deg offset
Changes Limits on both sides individualy in and out.
Nothing seemed to work it acts exactly the same no matter what changes are made the CW stops are just weak.
I think I will try another servo and see what the results are.
ZeXx86
Site Admin
Posts: 12832
Joined: Mon 29. Apr 2013 16:06:44
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Before trying another servo I recommend to check mechanics. New goblins have often tight mechanics especially in the rudder which mean troubles.
So you can check if there is everything smooth, because for rudder any force that servo must overcome plays a role. Even it is tight ball linkage and servo is very strong, it will slow the reaction.

The best to check the rudder is to unmount all blades, disconnect push rod from the servo arm and start the motor to flight headspeed.
When you will be able to move with push rod freely from one side to another (while motor is running), then mechanics is good. Alternatively it will be not possible to tune it perfectly until it will be smooth.
Spirit System developer
Russell
Posts: 22
Joined: Fri 26. Sep 2014 23:44:41

Ok I will try as you suggest.
Thanks.
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