Tail Twitching
02-21-2010 | 09:26 AM
#1
Tail Twitching
Hello All,
I have a T-Rex 600 with the futaba gyro and digital servo. After 110 flights I now have a twitch in the tail. It's like a rethymic "Tick-Tock" where the tail twitches back and forth about 1/4", nothing I do seems to fix it and it is always there. I checked all of the mechanical adjustments and maintenance and all seems to be okay. It's almost like an interference issue but I'm on 2.4Ghz and I'm sure that can't be the case. Does anyone have any suggestions as to what I can check for?
Kind regards,
Rick
I have a T-Rex 600 with the futaba gyro and digital servo. After 110 flights I now have a twitch in the tail. It's like a rethymic "Tick-Tock" where the tail twitches back and forth about 1/4", nothing I do seems to fix it and it is always there. I checked all of the mechanical adjustments and maintenance and all seems to be okay. It's almost like an interference issue but I'm on 2.4Ghz and I'm sure that can't be the case. Does anyone have any suggestions as to what I can check for?
Kind regards,
Rick
02-21-2010 | 12:41 PM
#2
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From: richmond, CA
RE: Tail Twitching
what kind of gyro and servo for the tail you use, also check the gain sensitivity of you gyro, maybe its high, that twitching thing i believe they call it tail wags, i got those if my gyro gain is high, so just lower the gyro gain setting, if it's remote you need to adjust it at your radio, what's the setting right now.
02-21-2010 | 01:54 PM
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From: middletown,
IN
RE: Tail Twitching
check and clean and relube your one way bearing. you may even need to replace it. i am assuming that this is set up like my t-rex 450. It will start to do this when the bearing is starting to go bad.
02-21-2010 | 08:23 PM
#4
RE: Tail Twitching
ORIGINAL: Ybenjulkay2x
what kind of gyro and servo for the tail you use, also check the gain sensitivity of you gyro, maybe its high, that twitching thing i believe they call it tail wags, i got those if my gyro gain is high, so just lower the gyro gain setting, if it's remote you need to adjust it at your radio, what's the setting right now.
what kind of gyro and servo for the tail you use, also check the gain sensitivity of you gyro, maybe its high, that twitching thing i believe they call it tail wags, i got those if my gyro gain is high, so just lower the gyro gain setting, if it's remote you need to adjust it at your radio, what's the setting right now.
I am using a Futaba 401 Gyro and a Futaba S9254. It was professionally set up and Gyro gain is set at 54% (JR 2.4Ghz) Transmitter. I Don't understand why after 110 flights it is not starting to act up. Maybe something needs to be replaced?
RP
02-23-2010 | 10:51 PM
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From: richmond, CA
RE: Tail Twitching
ORIGINAL: clarencem
check and clean and relube your one way bearing. you may even need to replace it. i am assuming that this is set up like my t-rex 450. It will start to do this when the bearing is starting to go bad.
check and clean and relube your one way bearing. you may even need to replace it. i am assuming that this is set up like my t-rex 450. It will start to do this when the bearing is starting to go bad.
RickP, have you also ground your tail; main bearing (shaft) to your motor mount, is your heli belt drive or torque tube type. I grounded mine to reduse the interference.
06-09-2010 | 04:14 AM
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From: RIVERVIEW,
MI
RE: Tail Twitching
I believe the tail twitching come from two areas. The first is simple. Raise the esc feature that allows an insensitive motor cutoff.In a couple of cases the tail twiching was related and caused by very quick momentary ESC controlled motor shut downs. (8 hours to find that one) The second is more difficult and the 401 appears to be the most prone. Static electricity generated by the belt in the tail drive system. After all if you look at a static electricty generator whalla! you have a tail rotor drive system. The carbon framed version appear the most sensitive. The following in order of effectiveness has help me eliminate the twiching.
1. Spray lube the belt with a graphite lube. I use Lock Ease. Also use the same on the bearings.
2. Spray drop coat the model with Static Guard.
3. Ground the tail boom to the main frame using a small wire.
4. Form a light weight 4 sided metal shielding box and mount the 401 inside of it. 3 sides and a bottom
If your issues appear better this time of the year it is because the static is less due to the higher humidity. Here in Michigan this is a wild problem in the winter months. Thanks, Dave [email protected]
1. Spray lube the belt with a graphite lube. I use Lock Ease. Also use the same on the bearings.
2. Spray drop coat the model with Static Guard.
3. Ground the tail boom to the main frame using a small wire.
4. Form a light weight 4 sided metal shielding box and mount the 401 inside of it. 3 sides and a bottom
If your issues appear better this time of the year it is because the static is less due to the higher humidity. Here in Michigan this is a wild problem in the winter months. Thanks, Dave [email protected]
06-29-2010 | 07:56 AM
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From: Sydney, AUSTRALIA
RE: Tail Twitching
has happened to me a few times, once a gyro & another tail belt. have my own check list.
SOLVING TAIL TWITCH</p>
Check all software settings, check gain & rate settings have not been increased.
Disable revo mixing.
Check ESC programing has not changed by a crash. (check motor & governor settings are the same)
Flight test if no change then mechanical check.
Check Belt, should be taught ie. not to tight & not to loose.
Check for binding in tail, check all bearings including tail drive shaft, tail shaft & bearings in tail rotor grips, bushes etc.
Lube & reasemble.
Check tail belt for missing teeth or worn flat spots. If found replace.(inspect gears if TT) Make sure belt has only one
90 degree twist in the proper direction.
Ground tail boom with a piece of wire to engine mount, could be static electricity interferance. Lube with silicone spray.
Flight test & if no change then;
Check main gear teeth & one way bearing is not binding. Make sure main shaft is not bent or binding on a bearing.
Flight test if no change then check tail servo & gyro.
Make sure both tail servo & gyro are properly mounted & have not worked loose. A loose gyro or servo will have this effect.
If you dont have a spare servo swap cyclic elevator servo with tail & flight test.
If still the same swap out gyro then test.
Problem should now be solved.</p>
06-29-2010 | 11:08 AM
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From: orlando,
FL
RE: Tail Twitching
ORIGINAL: flyurban
has happened to me a few times, once a gyro & another tail belt. have my own check list.
SOLVING TAIL TWITCH</p>
Check all software settings, check gain & rate settings have not been increased.
Disable revo mixing.
Check ESC programing has not changed by a crash. (check motor & governor settings are the same)
Flight test if no change then mechanical check.
Check Belt, should be taught ie. not to tight & not to loose.
Check for binding in tail, check all bearings including tail drive shaft, tail shaft & bearings in tail rotor grips, bushes etc.
Lube & reasemble.
Check tail belt for missing teeth or worn flat spots. If found replace.(inspect gears if TT) Make sure belt has only one
90 degree twist in the proper direction.
Ground tail boom with a piece of wire to engine mount, could be static electricity interferance. Lube with silicone spray.
Flight test & if no change then;
Check main gear teeth & one way bearing is not binding. Make sure main shaft is not bent or binding on a bearing.
Flight test if no change then check tail servo & gyro.
Make sure both tail servo & gyro are properly mounted & have not worked loose. A loose gyro or servo will have this effect.
If you dont have a spare servo swap cyclic elevator servo with tail & flight test.
If still the same swap out gyro then test.
Problem should now be solved.</p>
has happened to me a few times, once a gyro & another tail belt. have my own check list.
SOLVING TAIL TWITCH</p>
Check all software settings, check gain & rate settings have not been increased.
Disable revo mixing.
Check ESC programing has not changed by a crash. (check motor & governor settings are the same)
Flight test if no change then mechanical check.
Check Belt, should be taught ie. not to tight & not to loose.
Check for binding in tail, check all bearings including tail drive shaft, tail shaft & bearings in tail rotor grips, bushes etc.
Lube & reasemble.
Check tail belt for missing teeth or worn flat spots. If found replace.(inspect gears if TT) Make sure belt has only one
90 degree twist in the proper direction.
Ground tail boom with a piece of wire to engine mount, could be static electricity interferance. Lube with silicone spray.
Flight test & if no change then;
Check main gear teeth & one way bearing is not binding. Make sure main shaft is not bent or binding on a bearing.
Flight test if no change then check tail servo & gyro.
Make sure both tail servo & gyro are properly mounted & have not worked loose. A loose gyro or servo will have this effect.
If you dont have a spare servo swap cyclic elevator servo with tail & flight test.
If still the same swap out gyro then test.
Problem should now be solved.</p>
