Align GP750 on my Trex 450 suddenly started wagging. Please help

[Three6ty]

Hi folks.
Had an Align GP750 gyro on my trex 450 for a couple of months now along with a Hi-Tec HSG-5084MG tail servo and all has been good until today. Did first flight and all was fine. Then on second flight the tail has started wagging loads from side to side. I've played with the gain to try and dial it out but no joy. It either wags slowly on low gain or fast on high gain. Also got home this evening and went through the set up and still get this wag. I am absolutely lost why it has started happening. Anyone have any ideas on this? Also is there any way of telling if the servo is knackered or the gyro? Don't want to replace one and find its the other. Thanks for any help
Cheers, Rich

[sacko]

Check nothing is loose on the tail slide.

[TrexMADuk]

Check the mechanical set up too.... had one recently doing similar and one side of the tail grip was coming loose slightly - just tightened it up and the wag went away and was back to normal...

[TrexMADuk]

Snap !

[Three6ty]

Hi,
Thanks all. Think I've sussed it. One of the screws holding a tail grip onto the tail rotor hub had started to come undone and the grip was all loose. Going to locktite it all up now and give it a try.
Cheers, Rich

[sacko]

Seen it a couple of times now, glad its sorted

[Three6ty]

Hi,
Not quite sorted. The tail hub has a stripped thread. Couldn't tighten the screw holding the blade grip on. Never mind. New hub just ordered from FL.
Cheers, Rich

[p4ddy]

Would this create the same effect with a 401?? I have a vid up on here with my 450 doing the same but with a GP750 i was trying to see if it was the gyro

[ame=http://www.youtube.com/watch?v=mDXYxBQ3Ocs]YouTube - 450wag.MOV[/ame]

[p4ddy]

Check the mechanical set up too.... had one recently doing similar and one side of the tail grip was coming loose slightly - just tightened it up and the wag went away and was back to normal...

I checked my crashed 450 today & sure enough i had a tail grip retaining screw backed out way too far. Now i got to hope when i get the few bits i need that it's flying well again with a solid tail.

Thanks mate

[moonmanflyer]

9 times out of 10 if a sudden wag apears it is normanly mechanical.
Check the gyro pads, the align ones are useless and if the gyro starts to lift will cause this, best to replace with a futaba pad.
Bearings are also a main one to check, make sure they are all smooth in the tail gear box, and the front drive pully.
Check the belt tension, make sure it has not come loose.
Make sure the boom supports are tight, and have not come un-glued at there joints.
Check the thrust bearings in the tail hub, they might have fallen apart.
Make sure your tail blades are in good condition.
Check the belt for any missing teeth.
Make sure the control rod to the tail is running through the guides smoothly.
Make sure the pitch slidder is running smooth and the tail output shaft is straight.
If none of these then it could be a servo or gyro problem.

[Jamin_00]

tbh James I prefer the Spartan pads with the metal plate inbetween.

But the rest of it is sound advice otehr tahn the poor spleling

[moonmanflyer]

me Ben, i can't spell for shite and my lap top does not always seem to add the letters i hit, must proof read more often
And i still prefer futaba pads

[Three6ty]

Hi,
Paul (Geek) kindly gave me a tail rotor hub today. I fitted it tonight and all is well. The tail is now holding rock solid again.
Cheers, Rich

[Jamin_00]

Could have been the tail output shaft not allowing free movment also worth looking at the brass inserts on the tail grips as locktite gets on these all too easily and does not allow completely free movement causing the gyro to over compensate.

Have you still got the original tail box.

Worth checking if it allows the slider to move as freely as the one you are now using??

[Geek]

Hi,
Paul (Geek) kindly gave me a tail rotor hub today. I fitted it tonight and all is well. The tail is now holding rock solid again.
Cheers, Rich

Not a problem Rich.
sure I should owe you for all the pictures and Video's
We have had a good couple of days flying until today and the wind was to much. see you in the week