Raptor 50 SE Tail sloppy. Please Help

Hi all, My raptor 50se has movement from the tail which is like a swing to the right of about 2 inches then back to original position. Well nearly as it does gain ground - tail to the right over a minute in a hover. I tried adjusting the gain from 55 to 68 on the Dx6i display not true gain - but this only made the swing sharper. Changed the tension of the tail belt as I thought it may be a little tight but no different.
The Gyro is securely mounted and the leads are away from the frame for the first 3 inches.

I put a brand new DS655 on the tail of my Raptor 50 se as the old one gave up the ghost a good while ago so this one has only had a couple of flights.
I am using a Quark too and is set up matching up correctly to the servo used.
Took the main blades off and did the roll test with a spare main shaft and they both tip nicely together both ways. The blade tracking is good too.
Didn't have this problem with the old servo and I'm a bit stuck now. Can you help me out please.

Thanks
Dave

[maddog7]

Hi all, My raptor 50se has movement from the tail which is like a swing to the right of about 2 inches then back to original position. Well nearly as it does gain ground - tail to the right over a minute in a hover. I tried adjusting the gain from 55 to 68 on the Dx6i display not true gain - but this only made the swing sharper. Changed the tension of the tail belt as I thought it may be a little tight but no different.
The Gyro is securely mounted and the leads are away from the frame for the first 3 inches.

I put a brand new DS655 on the tail of my Raptor 50 se as the old one gave up the ghost a good while ago so this one has only had a couple of flights.
I am using a Quark too and is set up matching up correctly to the servo used.
Took the main blades off and did the roll test with a spare main shaft and they both tip nicely together both ways. The blade tracking is good too.
Didn't have this problem with the old servo and I'm a bit stuck now. Can you help me out please.

Thanks
Dave

I believe the quark needs the linkage to be totally free, any stickyness, however slight, seems to mess it up.
You should be able to move the tail linkage almost by blowing on it. Right from the servo horn backward.
Could also be be belt static perhaps?
D

[dbull46]

I believe the quark needs the linkage to be totally free, any stickyness, however slight, seems to mess it up.
You should be able to move the tail linkage almost by blowing on it. Right from the servo horn backward.
Could also be be belt static perhaps?
D

I never thought of the linkage. I'll have a look tomorrow.
How would i eliminate belt static?

Thanks
Dave

[maddog7]

It needs a ground strap from the tail gearbox pulley to the engine mount I think, actually, I might have just made that up, dunno if it only applies to electric helis? Someone less drunk than me will surely put me right.....

think the linkage is more the likely issue.
Hope you get it sorted.

[dbull46]

Lol ok thanks.

[hanson]

Hi all, My raptor 50se has movement from the tail which is like a swing to the right of about 2 inches then back to original position. Well nearly as it does gain ground - tail to the right over a minute in a hover. I tried adjusting the gain from 55 to 68 on the Dx6i display not true gain - but this only made the swing sharper. Changed the tension of the tail belt as I thought it may be a little tight but no different.
The Gyro is securely mounted and the leads are away from the frame for the first 3 inches.

I put a brand new DS655 on the tail of my Raptor 50 se as the old one gave up the ghost a good while ago so this one has only had a couple of flights.
I am using a Quark too and is set up matching up correctly to the servo used.
Took the main blades off and did the roll test with a spare main shaft and they both tip nicely together both ways. The blade tracking is good too.
Didn't have this problem with the old servo and I'm a bit stuck now. Can you help me out please.

Thanks
Dave

it could be the gain just needs dropping. what was the servo you took off? was it the same frame rate?

[dbull46]

Hello Hanson
The old servo was an Align DS620 and I think the frame rate comes under this description.
Motion speed:0.09sec/60°(4.8V)
0.07sec/60°(6.0V)

The new servo is a DS655 and the spec is.
Motion speed:0.06sec/60°(4.8V)
0.05sec/60°(6.0V)

hope this helps

[hanson]

Hello Hanson
The old servo was an Align DS620 and I think the frame rate comes under this description.
Motion speed:0.09sec/60°(4.8V)
0.07sec/60°(6.0V)

The new servo is a DS655 and the spec is.
Motion speed:0.06sec/60°(4.8V)
0.05sec/60°(6.0V)

hope this helps

yeh, they are both 1520us from what i can tell. it might be worth trying decreasing the gain, as long as the tail holds then there is no reason to run a high gain. it might explain why the last servo packed up. as maddog says though a smooth linkage is key to a good tail, that would be my first check

[dbull46]

The only difference between the two specs I could see, was that the motion speed on the new servo is faster but it's only nano seconds though!

I'm going to take her out this morning after looking at the linkage.
Speak to you later.

Thanks alot

Dave

[pgkevet]

Agree likely the gain needs backing off a touch ..but also a beliver in setting up any tail linkages to hold steady in a hover in rate mode; holds way better then in HH. And as has been said pay attention to any roughness or binding in tail travel

[waveydavey]

Agree likely the gain needs backing off a touch ..but also a beliver in setting up any tail linkages to hold steady in a hover in rate mode; holds way better then in HH. And as has been said pay attention to any roughness or binding in tail travel

i always set up the tail in rate mode like you but does it really make any difference. The more I've though about it the only thing it can help is that the servo isn't working so hard. With no input from the tx then the gyro should hold the Heli heading. If there's a tendency to rotate either way the gyro would surely just add opposite.

you might run out of right rudder and the tail stops would be rough but it should hold a heading.

[dbull46]

Guys. I come back from flying with my tail between my legs and head down in shame.
In my original inspection I failed to spot a school boy error. The servo lead was pushing down onto the gyro lead about 2.5 inches from the gyro transmitting vibration through to the gyro i think.
Now I've separated them both she's back to flying nice.
Please don't think you've wasted you time though cos I've picked up some really useful setup tips. Like the gyro gain set to high can reduce the life of the servo, and a stiff linkage can impair performance of servo.

Thanks
Dave

[maddog7]

Mate, pleased you got it sorted and that you fed back what the solution was...

[dbull46]

Thanks maddog.
And thanks to all of you for helping me out