Tail tuning chatter

[sctholson]

Hi Guys,
Okay I flew twice on Sunday and both flights the tail chattered when I made a right turn. Not to the left, or fast forward. Between the flights I turned the tail gain down roughly 4 points or so. I think the tail gain is now around 52 and I still have this chatter when I turn right.

Should I continue to reduce the overall gain, or am I ready for fine tuning and if so, can anyone make a suggestion what I should try and what to expect?

Thanks

Scott

The photo of my flying buddies with my machine in the background, note icicles below the heli. It was 23 degrees

[x50B]

Check the tuning procedure. ...adjust tail rod length until stops are equal on both sides....a few turns at a time...then raise up the gain.

[Starving Bushman]

How would the tail rod length effect stops? As long as you have maximum travel in each direction without binding, how does the length of the tail rod come into play?

[Dirtyburd]

I believe tail resolution is also a big factor as well. I am currently having the same issue on my goblin 570. My endpoints were at 70 on both left and right with a 16mm servo horn length. At this setting I still had chatter at a gain of 50. I dropped the length down to 14mm and got endpoints at 90 on both sides. Waiting for the rain to quit to test it out, but believe with this resolution, I will be able to run a higher gain with no chatter.

[sctholson]

How do you get endpoints on the tail of 70 on both left and right (or 90 and 90)? Was that full travel?

My stops are 125 left and 93 on the right. At these settings the slider is about 1mm away from both the hub and tail box. I assumed this discrepancy was by design since the pushrod is shortened by two turns on set up.

[Dirtyburd]

Here is how I set up mine. I center servo so that horn is 90 degrees from pushrod. Then I adjust pushrod until tail blades are even at 0 degrees. Next, I turn pushrod 1-2 turns giving blades a slight pitch against torque. This usually gets me even endpoints on both sides. If I have to increase my endpoint values, i reduce horn length. If you have to reduce endpoint values, increase horn length. In my case I reduced my horn length from 17mm to 14mm and this changed my endpoints from 70 to 91 on both sides. I think if you adjust your pushrod length correctly, your endpoints should be close. If there is not enough adjustment on your pushrod, you may have to move horn a spline over to where it is slightly off of 90 degrees to get even endpoints.

[KSHeli]

I have never had equal endpoints and no chatter, I believe the chatter is gain to high. Even popokatepetl says you endpoints may not be equal just try and keep the max below 90 for resolution. 0.5-1.0% gain to high may cause high speed blade chatter. Also check your governor gain value ir your using a gov this can also cause the tail to chatter, that's what usually causes it on mine.

[dsduani]

I had a similar problem that did not improve with changes in gyro gain or the tail mechanics. Decreasing the P-gain on the tail gyro page took care of it.

[Dirtyburd]

Tested out the changes I made. By reducing my horn length, I was able to get the chatter to stop at a gain of 53 with endpoints of 91. I also reduced the p gain by one point and now tail is rock solid.

[LoveToFly1]

i have read many different things. i have read the BD guys say do as the wizard says and offset the slider, i have read the same people say do not offset the slider. i dont know what to do..hahaha...i just adjust my pushrod length so my endpoints are the same and forget about where it is in the middle. my tail doesnt drift, it holds well too. now my tail bounces when i stop in both directions no matte what i do with delay, i even replaced all the bearings, hub, and grips once to no avail, but i just stop smoothly with my thumb now instead of trying to stop abruptly. it works