START HERE |
|
Register | FAQ | PM | Events | Groups | Blogs | Calendar | Mark Forums Read |
Unregistered
|
Skookum Robotics Skookum Robotics SK-360 SK-540 & SK-720 Digital Flybar |
|
LinkBack | Thread Tools | Display Modes |
09-26-2014, 09:42 PM | #1 (permalink) |
Registered Users
Join Date: Nov 2013
|
Low head speed scale.....tail wag help
I'm running a skookum sk720 in a 700 size Jet Ranger with 600 mechanics and 112mm tail blades. My head speed is right about 1400 and smooth. The issue I have, is my tail consistently and methodically wags side to side slowly a few millimetres. If I go into idle up 2 (1650 head speed) it is less noticeable. My tail gain is set to 65% so I'm wondering if I need to up that to get rid of the wag? Is there any other fix? Should I just run the head speed higher, giving up the scaleness to functionality? If I run my head speed any lower, I fear my esc and motor will overheat. I also start to get many vibrations through the fuselage if I run headspeed lower. I don't really know how to eliminate these vibrations, other than keeping my headspeed higher. I do have a slight vibration coming in at 10, but it's not that kind of a wag. Self tune Bell gains are on. Main blades are 700mm carbon, balanced, tail blades are Edge 112mm, Gearing is stock for 600esp, ESC is CC 120hv, motor is savox 910kv, servos are hyperion digital. Skookum settings are stock "scale" set to my need for centers, etc. +8 - 3 on pitch, tail holds great, everything works as it should...... EXCEPT my tail slowly wags left to right a few millimeters while hovering. I turned up my tail gain to 80 and it's still there.
|
Sponsored Links | |||
Advertisement |
|
09-26-2014, 09:50 PM | #2 (permalink) |
Registered Users
|
No you can run at that speed. Low headspeeds need alot more gain. Especially once you go below 1600 or so on 600 or 700 machines, it gets alot more noticeable.
First thing is double check the tail mechanical gain is properly set. The L/R endpoints should be close to 100. That's step #1. From there on it's just tail tuning. Don't be afraid of higher gain numbers, if it's coming out of a proper setup. You will probably need to change tail banks according to throttle. Not uncommon. Is there any way you can change the tail ratio? Some machines have different gearing for tail gears. Raising the tail ratio so the tail spins faster would benefit alot.
__________________
YS Powered Rave ENV Stretch Protos 500, Stretch Mini Protos, 180 Trio |
09-26-2014, 09:55 PM | #3 (permalink) |
Registered Users
Thread Starter
Join Date: Nov 2013
|
My tail servo endpoints are L-112, R-141, Center- neg12
I can't find rate gain since upgrading to 4.0. Not sure what mechanical gain is or how to adjust it (maybe i just don't understand this term?) I've looked at changing tail ratio, but can't find a whole it of info about it. I will up the gain in my TX even higher than 80, see what it does. If I could fly and video at same time I'd post it up lol. |
09-27-2014, 07:24 AM | #4 (permalink) | |
Registered Users
Join Date: Sep 2008
Location: Smyrna, GA
|
Quote:
All helis need the correct balance between mechanical and electronic gain from the gyro. Too much mechanically and the servo may overshoot and bounce, and you will be forced to run very low electronic gain, and helis tail may feel loose. Too little and the servo wont be fast enough to keep up with the small adjustments that are needed by the gyro to hold the tail, and you will be forced to drive the electronic gain up very high which in turn will cause tail wag. The tail end points that show in the software give us a guide for where that servo ball and mechanical gain should be for the Skookum to achieve the proper balance. You want to use the hole that will get you as close as possible to around 100 on the end points. It doesn't have to be exact, and its normal for some to have a higher number one side than the other due to the way the pitch arm slider is made. In your case, you want to try and move your tail servo ball out one hole and speed things up a bit mechanically. That 141 is too far off from where it needs to be, and should be showing in yellow in the software indicating this is too far out of bounds. Yellow within any setting in the SK software is a bad thing. The other side may drop below 100 after moving the ball, but that's ok, and it will still be within acceptable range. You will want to re tune your electronic gain again after making this change. BTW, setting rate mode is easier now on V4. Simply check the box on the tail tab
__________________
Tony Synergy 516, Gaui R-5 Speed (RIP), Cypher Vtol Jet (RIP), Spirit FBL, Hobbywing and Scorpion Tribunus ESC, Xnova motors. The girl in my DX9 tells them all what to do |
|
09-27-2014, 07:50 AM | #5 (permalink) | |
Registered Users
|
Quote:
__________________
YS Powered Rave ENV Stretch Protos 500, Stretch Mini Protos, 180 Trio |
|
09-27-2014, 02:05 PM | #6 (permalink) |
Registered Users
Thread Starter
Join Date: Nov 2013
|
Thanks for the explanation! I'll set it up and report back
|
09-27-2014, 04:34 PM | #7 (permalink) |
Join Date: Mar 2007
|
=] you don't say if this has just started to happen?
__________________
|
09-27-2014, 05:27 PM | #8 (permalink) |
Registered Users
Thread Starter
Join Date: Nov 2013
|
It has always done it, but not to this extent. It has been inconsistent up till now. But.... I've changed things like main blades, tail blades, added bit of weight, changed tail box from V1 trex 600 to a V2 trex 700, and changed from skookum 540 to 720.
|
Thread Tools | |
Display Modes | |
|
|