help with EK2-0704B and futaba 6ex

[draco1970]

Hi all I have belt cp, I am quite new to RC heli's and I have to be truthful they are awesome:noteworthy. But I have got a few upgrade parts that I am having problems with.a new esky HH gyro EK2-0704B and my futaba 6ex controller:thinking.i have setup the controller everything seems to move correctly, but I am getting creeping on the tail when I change the yaw. It moves cw ok, but then it creeps back to centre position very slowly, work perfect ccw. i have changed the tail main shaft. Does anyone have an idea? I have upgraded to sg 90 servos and I thinking that the servo might be duff. Please can you help thanks? Sorry forgot to mention .

[sutty]

Others will perhaps disagree, and to be fair I have only used the 704A gyro, but in my experience it is almost impossible to eliminate creep altogether when the gyro is operating in HH mode.

The good thing about this is that the creep really isn't relevant because you are trying to set the gyro up when the helicopter isn't free to rotate. Even the tiniest of off centre trimming will be perceived by the gyro as a command to move the tail, when it doesn't move, it has to add more command to the tail, to correct this apparent failure to respond to the command, and this just escalates. If the tail were free to move it would achieve the new position and the gyro would calculate that the tail had moved as it should and would stop increasing the servo throw. In other words it will work fine if you are flying or if you use a turntable to do the set up.

This behaviour is by design. Consider the circumstance where the tail was being held by the wind, and you give a command to move it but the wind was stopping it, the gyro would continue to increase the servo throw until it detected that the tail had moved as commanded. The difficulty arises in trying to trim the rudder to such an accurate degree that the gyro is not receiving any signal at all, suggesting that it should move.

Follow the sticky guide for setting up the gyro with the DX6i and you will not go far wrong. Try to minimise the creep and then give it a test fly, I'm sure you will find it will hold perfectly well.

[draco1970]

thaks i will give it a go.:rolling

[draco1970]

well i gave it a go, when it was off the ground i put a bit off left hand yaw and it started to spin to the left uncontrolably had to give a load of right to compensate and ended up bending the tail shaft. lucky i have had a couple in reserve. do you have any other ideas thanks.it seems that when you move the tail in a direction it does not return when sticks are centerd and i thought that was the idea of a head lock. when it is in normal mode it seems fine. any help much appretiated.:arggg:

[sutty]

Sorry to hear you bent your tail boom but I'm pleased you had one in reserve. What you describe now seems to be something far more fundamental than a little creep from the rudder servo. I had those symptoms when I had my gyro mounted the wrong way up. I don't think you can do that with the 704B. The sticky used to have some pictures for the mounting of the 704B, but I can't see them now. I recall that it is completely different to the 704A which has to be mounted vertically. I am pretty sure this one has to be flat.

Since it has a flat mounting, it probably needs to be equipped with a reversing switch also. This allows you to reverse the way the gyro provides feedback to the servo. This is necessary in case you need to mount it on the underside of the heli. If you had the reversing switch set the wrong way it would definitely cause the symptoms you describe. I have seen this happen and it was exactly as you described. My gyro was the wrong way up (same as incorrect reversing switch setting). I went up a few inches and for a few seconds all was stable then I added a little rudder and then zoom, all the way around in a second. Tried it a couple more times just to watch and then searched for the solution, which was to turn my gyro over.

In your case the solution could be as simple as flicking the reversing switch. I think I recall that it has one. Yes it does, see here.

http://www.twf-sz.com/english/products.asp?prodid=0278

What happens is instead of correcting for tail movement it adds to it, so once the tail sets off moving the gyro kicks in to compensate and begins correcting, slowly at first but then the situation gets worse, so it adds some more correction, worsening the situation yet again, and so it goes on. Soon this positive feedback has escalated into full throw on the servo in the direction it was going. If you had steered right the same thing would have happened in that direction.

When you try this, try to maintain a very low hover, so that you can bail out quickly without damage. You will soon know if it is corrected. If you are not confident of holding a low controlled hover then I suggest making a turntable device for your helicopter. I have seen some good examples just by searching on google. One guy I saw on youtube simply used a fan mounted on its side. Another used an old PC hard disc, see part way down here.

http://www.heliguy.com/Forum/helicopter-turntable-t25859.html (http://www.heliguy.com/Forum/helicopter-turntable-t25859.html)

Here is another one.

http://www.youtube.com/watch?v=T3NILJoAMJc&feature=related (http://www.heliguy.com/Forum/helicopter-turntable-t25859.html)

There are lots of ways to make one.

I hope this helps, good luck.

[draco1970]

thank you for your time i will give it a go and let you know what i come up with thanks:Bang

[draco1970]

Hi there I have tried it in rev and normal and it is doing the same, I have set it up on futaba 6ex but still the same mmmmmm starting to get a bit annoyed. Think I will try to set up a jig for the heli to test the tail. Will carry on struggling! I find it odd that the new headlock giro does not work with standard receiver, now there is something I wished I had seen before getting it lol. O well that is the way things go. Thanks for your help it is much appreciated.

[starfreak]

Hi there I have tried it in rev and normal and it is doing the same, I have set it up on futaba 6ex but still the same mmmmmm starting to get a bit annoyed. Think I will try to set up a jig for the heli to test the tail. Will carry on struggling! I find it odd that the new headlock giro does not work with standard receiver, now there is something I wished I had seen before getting it lol. O well that is the way things go. Thanks for your help it is much appreciated.

Hi,

I have use this gyro and it work great :clappp. I also use towerpro 90 but It will work better if you use esky digital servo with this gyro. You can gain the gyro through tx. so hope this help.:lol:

[mnwizard]

.......or if you use a turntable to do the set up.....


Great minds! I actually have a old turntable on my bench that I'm modding to hold a Belt while I adjust the tail servo and gain. :)