600 N tail wag

[stanley]

I have been trying all week to resolve my heli tail wag after a "heavy landing" and replacing all damaged parts mains/boom/skids I cannot get the tail to hold
my set up is DX 7, AR 8000, CSM 720/belt drive on tail/with "ye olde flybar" this Heli has been faultless before my rebuild and now each time i take off the tail just wags rapidly from side to side even if I take the gain right up to beyond 90% or as low as 60% the wag is there and does not alter in frequency just a constant rapid wag
I can rule out my TX as my 550 flys perfectly mechanically everything is spot on I have been through the heli nose to tail and all is perfect
what am I missing ???

[waveydavey]

I'd go for something binding on the tail rods from either the servo or from the bellcrank, make sure there is nothing locked up or even slightly raises the friction

[stanley]

Thanx for the input WD I have had each and every component apart to check for free movment without any binding/friction
new parts fitted
mainshaft
feathering shaft
flybar
bladegrip bearings (thrust and radial)
main gear/auto gear
tail rotor shaft
tail servo flown on my 550 no problems
new gyro foam
different TX channel tried (no different)
re bind
gyro re calibrated
range check no problems
remaining calm and methodical
main blades balanced and C O G in order
tail blades checked
tail rotor hub checked
tail drive belt twisted once only
dont know what else to try ?

[Pabs]

belts not slipping is it? right tension?

[waveydavey]

If you remove the servo to bellcrank linkage is it nice and free running?

Do you use the plastic pitch slider with the alloy pitch lever?

[johnsandywhite]

Try a different Tail Servo Stanley.

[stanley]

Thanx for all the input Pilots, belt is new tension correct, pitch arm is alloy, as above John tried the DS 650 from my 550 same wag
however whilst re re checking my set up my DX 7 TX suddenly lost all its memory settings all I have now is a default screen on all 20 channels so maybe my trusty DX7 of 2009 vintage has cried enough ? Im over in the UK next week so will treat myself to a new TX
once again thank you all for your input
PS not missing much here John rather windy !!!

[johnsandywhite]

Thanx for all the input Pilots, belt is new tension correct, pitch arm is alloy, as above John tried the DS 650 from my 550 same wag
however whilst re re checking my set up my DX 7 TX suddenly lost all its memory settings all I have now is a default screen on all 20 channels so maybe my trusty DX7 of 2009 vintage has cried enough ? Im over in the UK next week so will treat myself to a new TX
once again thank you all for your input
PS not missing much here John rather windy !!!

Sorry to hear about the DX7 Stanley. If I was there, you could have borrowed my Sim DX8 until you get sorted. Not missing much? I wouldn't mind the wind, but the weather here is CRAP. Finally got to fly with our Simon yesterday. We had 5 flights each with our Trex 550FBL. Sunny at times, cloud building and wind not too bad. Enjoyed flying for the first time since I flew with you at Tormos. I have just bought our Simon a Blade 450X for his 40th Birthday on Saturday. Hope you get sorted soon.

[Rob O]

Re: 600 N tail wag

I see you replaced the gyro foam pad , did you use the same type mate ? . Just a thought .

[waveydavey]

If you remove the servo to bellcrank linkage is it nice and free running?

Do you use the plastic pitch slider with the alloy pitch lever?

Depending on what variant of pitch slider you fit depends on wether it binds or not. The new pitch lever with the plastic bush in it and using the plastic pitch slider will cause binding, the stand off on the slider interferes with the plastic bush. The old lever is fine and the new one must be used with the alloy slider

[stanley]

Yes Rob I used the same gyro foam I have a roll of Maplins finest double sided tape with a tape/alloy plate/tape set up used this product on my nitros and electric for 2years now with no problems
I have the alloy pitch arm with the alloy slider bush fitted when I detach the tail rod from the servo the the action is silky smooth
as above I am now suspecting an expired DX 7 ?