Flymentor problem: Tail Servo swings hard right on power up

[Steve Joblin]

I finally got my Flymentor installed.

I think I have sorted out my Aileron, Pitch, and Elevator servos... I still may need to play with the settings a bit, but the basically operate the way they are supposed to.

My problem is my tail servo. When I power up, it swings hard to the right and tries to keep going right (but it is mechanically being stopped by the linkages). I've switched servo directions, but nothing I do seems to change the behavior.

Anyone experience anything like this issue? Any ideas of what could be causing it?

[pril250]

In order to set the FM tail gyro you need to reduce the gyro gain in Helibal into the normal zone where it is in rate mode rather than HH mode. Once you do that the gyro should center the servo, if not that is where you mechanically set your links to do so. Also the distance on the ball link (mechanical gain) should be set correctly for the size of the heli. You can then start to set the correction and rudder direction. Hope this helps.

[Steve Joblin]

Finally isolated the issue! my Tail Gyro is bad! Always something! My Tail Servo was a cheap analog servo... I must have fried it when I hooked it up to my new GA-250 gyro (which in reading the manual, says you must use a DIGITAL servo). Although I am bummed, I am glad I isolated the issue and know why it failed!

[Ivor Hill]

Piezo gyro's will allway's move to one end of the travel in HH mode ( including the FM tail gyro ) and it is not a problem. If the travel is to much then it should bre reduced useing the FM programme.
As Pril said it will move to centre in normal mode and so the tail should be set up in normal mode before changing the HH.

[Steve Joblin]

I took everything apart and started from scratch. The first thing I did was to just hook up the ESC, my old Detrum GY48V Gyro, and Tail Servo to my RX. Nothing else. I powered it up and the servo slammed hard right and tried to keep going right. I disconnected the servo and replaced it with another cheap servo that I had laying around (not digital). I powered it up and it worked as expected. Thus, I have determined that the servo is the bad component. I will have to order a decent digital tail servo to continue with the installation process.

[cr@sh]

[QUOTE=Ivor Hill;4055465]Piezo gyro's will allway's move to one end of the travel in HH mode ( including the FM tail gyro ) and it is not a problem. If the travel is to much then it should bre reduced useing the FM programme. ....

hey, Thanks man...ive been trolling forums for an age, trying to find a definitive answer as to why the FM tail moves to one end and stops....people have been saying that it's normal behaviour but its NOT. ....not for all of my other gyros (mems gyro's).

you explain it simply, its a piezo gryo, and thats what piezo gyros do..

im on the verge ...almost ready to pull this FM unit off my heli. my tail wont hold.
i am an experienced pilot, just thought id give this fly-mentor a crack on my atom 500, to make it less squirrelly with the big fancy moves ;-)

anyway, thanks.

mike.

[cr@sh]

ok, i just spent a few more minutes with the atom FM equipped.... i decided that it was far from a tail wag situation ( tail mechanics silky smooth) so i upped the tail gain, using the FM software from 70 to 80, the tail now has a rock solid stop ccw.... still a funny bounce in a clockwise piro but hey.... im almost there, i have renewed faith. the swash balancing i had set to zero (off condition) so that i could concentrate on the tail.... set to 70... this proved to be too much gain...heli was all over the place, i settled on 40, shes pretty stable now =).

by the way, if people are having problems trying to get the flymentor software to work, i found that changing the com port settings in windows got it working, simply choose a com port not in use.

windows xp: device manager/ports (com&lpt) /kds link line.
i changed mine to com2 which was un-used on my computer, and viola!!! it connected to the
heli =)

good luk people!!!!

mike.

[sparrow06]

Not jacking the thread but i have the same issue. i am using a FM gyro and the gray wire is connected to the RX. i did set my gyro gain to 50% on my TX and 0% to my programmer. then i did center my tail pitch slider. but when i tried to hover it and set my gyro gain to 70% on my TX and my FM programmer my helicopter is just turning CCW turning left so bad. i really need to sub trim is so bad to the right at least 100 click to stop it

[Ivor Hill]

Originally Posted by sparrow06

Not jacking the thread but i have the same issue. i am using a FM gyro and the gray wire is connected to the RX. i did set my gyro gain to 50% on my TX and 0% to my programmer. then i did center my tail pitch slider. but when i tried to hover it and set my gyro gain to 70% on my TX and my FM programmer my helicopter is just turning CCW turning left so bad. i really need to sub trim is so bad to the right at least 100 click to stop it

Centering the tail pitch slider is not going to make it work. Please read the sticky at the top. The tail must first be set up mechanicaly in normal mode ( servo centred ) and with little or no gain set. adjust the position of the slider untill the tail holds without useing trim or stick then switch to HH and set the best gain.
If it is a trex or trex clone you will end up with the slider offset towards the boom, the tail will not be perfect but it will hold.