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tail wagging but gain set to 0

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tail wagging but gain set to 0

Old 11-19-2006, 04:53 AM
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Default tail wagging but gain set to 0

I have just replaced the tail belt in my SE. Couldn't get the tail boom off so I managed to put in the new belt using the tension that was set for the old belt. Finger test can move the belt with medium force not too light not too heavy. Just before I start applying what I could call strong force its already at its 3/4 waypoint.

Problem - Was experiencing bad tail wag, then when returning to hover its kind of okay. So set my gyro to zero gain, much better but I still get a small amount of tail wag from time to time not alot though. Also I noticed just before spooling up, I left it at low rpm and sounded like the rpm what pulsing. Alternating high - low pitch sound. Then I spooled up didn't take off on purpose, powered down to replicate pulsing but couldn't was ok after that.

What could it be. Belt too tight, too much silicon spray on the belt?
Old 11-19-2006, 08:52 AM
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Default RE: tail wagging but gain set to 0

The tail was pulsing??? Watch the linkage on the tail rotors to see if this is the pulsing you're talking about.
Old 11-19-2006, 09:01 AM
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Default RE: tail wagging but gain set to 0

Pop off the linkage on the tail and make sure it is smooth to move left and right.
Old 11-20-2006, 06:51 AM
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Default RE: tail wagging but gain set to 0


ORIGINAL: shag555

The tail was pulsing??? Watch the linkage on the tail rotors to see if this is the pulsing you're talking about.

Not sure if the tail was pulsing but sounded like the headspeed was fast-slow-fast-slow. Sounded like vroom-deeeeer-vroooom-deeeeeer-vrrooooom, as if throttle up-down-up-down fast alternating. Couldn't replicate it after applying alot more power, then backing off.

Should I be using silicion spray as a lube for the tail slider. Sewing machine oil would slide better but catch alot of dirt so prefer not to use that.

After looking at the forums could be my analog tail servo. I do have a spare digital one which I might try.

I'll check the tail slider movement.
Old 11-20-2006, 03:52 PM
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Default RE: tail wagging but gain set to 0

Yes you should be using a digital on the tail. An analog servo will be trying to catch up all the time, making the servo motor very hot and you will then get lag which will make things worse. I would recomend a Futaba 9650 for the tail.
Old 11-21-2006, 07:32 PM
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Default RE: tail wagging but gain set to 0

Keeping everything hooked up, take your fingers and try to move the tail blade pitch as if the servo was doing it. Does it have any play? If it does watch the tail shaft. Does the tail shaft move in the tail case/bearings? If it does you have to shim it with washers.
Old 11-22-2006, 01:14 AM
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Default RE: tail wagging but gain set to 0

You can use analog servos just fine on the tail as long as they're quick (around 0.9). I've flown analog on many helis, and while they don't even come close to the precision that using a 9254 on the tail does, they work well enough not to wag or cause serious tail problems.

Sounds to me like you've got mechanical binding somewhere, OR, you've enabled the governor mode on your ESC somehow. Alot of ESC's with gov's don't get along well with the GY401, and they can often fight eachother, causing tail wag and headspeed jumps.

That would also explain your motor pulsing. Give it a shot, you need to eliminate one thing at a time when troubleshooting helis, much the same way you do with computers.
Old 11-22-2006, 07:06 AM
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Default RE: tail wagging but gain set to 0


ORIGINAL: credence

You can use analog servos just fine on the tail as long as they're quick (around 0.9). I've flown analog on many helis, and while they don't even come close to the precision that using a 9254 on the tail does, they work well enough not to wag or cause serious tail problems.

Sounds to me like you've got mechanical binding somewhere, OR, you've enabled the governor mode on your ESC somehow. Alot of ESC's with gov's don't get along well with the GY401, and they can often fight eachother, causing tail wag and headspeed jumps.

That would also explain your motor pulsing. Give it a shot, you need to eliminate one thing at a time when troubleshooting helis, much the same way you do with computers.

I did have governer mode enabled. I originally purchased the heli already built as it flew wonderful until I crashed it, so from the start it was using governer mode. Its all repaired just the tail as never been the same. I have free movement in the tail slider. tail rod not binding. I just replaced my analog tail (SS-100) servo with a new digital one ([link=http://www.wattsuprc.com.au/product_detail.asp?pid=TADS03]HDS-477[/link]) that came with the heli, and its worse. goes crazy doing a few 360's on the ground. The analog servo I have is much better. but yeah looks like the tail gets stuck in either direction with full movement when rotating. it whizz's 360's in one direction, apply opposite rudder then does 360's in other direction, but still on the ground tail always return to centre. I did reprogram the ESC & took off governer mode, no difference.
Old 11-22-2006, 07:42 AM
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Default RE: tail wagging but gain set to 0

Ok worked it out. Before with my analog servo I had to reverse the plug, & I left it like that. Of course on a digital servo if you reverse the plug it wont work, so had no choice. hence the crazy 360 turns. Then I switched the A B reverse slider on the 401gyro & perfect. (: Damn that digital servo is nice n fast (:

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