More Gyro problems

[inhissteps]

Ok Here's the deal. I have a Hawk Pro with a Futaba GY240 Gyro. TX is a Futaba 7 CHP The tail servo is a Hitec HS-425BB..transit time is not the highest but it serves my purpose for mild flying at the moment when the cash flow is low.
Here's the problem. I can trim the tail in rate mode and all is good, Trims and centered and no loose linkages or slop. As soon as I lock in HH I can't get enough right trim (the revo mixing is INH at this point) I have flown this setup on another heli just fine only 3 days ago all was working fine when I installed it and worked even better when I pulled it off. Now I can't seem to get a locking tail.

Its really ticking me off. any ideas????

[keithgr148]

question you moved it from one heli too anther heli ?? check the wires I had the same problem and the 401 would not lock on HH. I sent the gyro back to futaba for repair .

[cassat]

Try upping the headspeed or put it on an old Concept for testing.

[inhissteps]

Yes I moved the gyro from a concept 30 to the Hawk. I dubble checked the wires and all is good.
My head speed is nice and hot also. I tryed lowering the head speed but that did'nt work. Also adjusted the gain down so not to get wag but wag is not the issue.
When I trimed in rate mode and then jump into HH I need aprox 1/2 of my right stick to keep the bird straight. Once it straight it seems to hold ok (but not great, this could be where the wag comment could come into play)....its just strange why I can't trim out.

Is there any other setting on my tx, (other then revo mixing) that may play a part in this problem?

I'm sure this is not a issue but..
Rud dual rates are at 100%
EXP dual rate are at -30
E-points are 100% (no binding)
linkages are at 90 degree's

I really don't want to start adjusting linkages when there may be a bigger problem looming.
I also have a Logictech 2100t for my X-400. I may try that and see if the problem goes away.

[Heli_Gal]

Please read the following article for tail setup..

http://www.helifever.com/articles/27/1/Trimming-an-RC-Helicopter

[cassat]

Go into D/R EXP menu and check channel 4, make sure exp is zero and let us know.
You don't need much stick to turn left wherever exp is set!

[inhissteps]

Thanks for the link but it really does'nt give much into on the tail or problems that occure with gyro's
I have done some searching on this issue but hav't come to to many conclusions. I hope there is some revelations on this issue.

[Phil Noel]

10 easy steps:

1 - Make sure no trim or sub-trim is present
2 - Connect the servo directly to the rudder channel and turn on
3 - Now mont the servo horn so it is at a right angle (90*) to the servo case.
4 - Turn off the radio
5 - Hookup the gyro with the servo plugged into it
6 - Set into yaw rate mode and turn the radio back on
7 - Hover the heli and DO NOT touch the electronic trim on your TX, but trim for no yaw by adjusting the length of the tail rotor control rod.
8 - Shut the heli down and switch the GY-240 into HH mode and turn it back on.
9 - Adjust the end point trim pot ON THE GYRO so that as you turn the tail rotor there is no binding of the servo, or control bellcrank, as you move full left rudder and right rudder stick.
10 - Now hover the heli in HH mode and sdjust the bgain for no wag

For a better understanding of these gyros, you may find this article of interest.

http://www.leisuretech.ca/hints_gyro.html

[cassat]

Let us know when your EXP is reset so we can move forward

[inhissteps]

I started will all values at neutral, All steps covered in previous post has been covered actually more then once. I added in a little exp to control the tail just a bit. I have a heavy thumb..lol. It did'nt seem to change anything other then the typical exp properties. Added it was the only value that needed adjustment, The exp was added in after 3-4 spool ups. 2 min apx each.

[inhissteps]

Thank you Phil for that link there is some great stuff there.

I'm heading out to the field in the morning for more testing, trimming and HUCKING.....You know the funny part is that I have had this heli for 3 years and have yet to have a great flight..there always seems to be something wrong......anyone want a HAWK??? I'm no novice around the heli's but I swear this one is possesed......better yet...Does any one want to do a Excorsism?

[cassat]

Why would you add exp when you say that you have to move the stick too much??
Kinda contradicting............ + 5 -5 = 0

[inhissteps]

I wanted to soften the first to mid part of the servo movement so I could control the tail even though i had to give right stick, I reutrned it back to normal after I shut down. I should'nt have even posted that exp value change because it was not even significant as i tryed many other things before doing this. I just wanted everyone to know as much info as possibe as to what I have tryed and what has been done to rectify this dilemma.

Just made a few new changes as per Phil's gyro write up. I will give it a try in the morning and let you all know.

Thank you to all who have posted with ideas thus this far!

[inhissteps]

OK So I just got back from the field and WOW!!!!!!!. I HAD THE BEST FLIGHT EVER.
I set the tail up as per phils write up. (I needed to lengthen the control by about 3 turns. Once YR and HH where set up on the bench..It pritty much flew straight out of the box.
I had adjust the gain down because of a small wag problem. The Gyro locks hard as rock and it piro's like a tornado!!

Thank you to all who help me figgure this one out. The cool part is now that I have gone through this epasode of gyro trouble I have learned so much more about my heli. Thus making this great Hobby of R/C so much more fun.

Cheers

[Phil Noel]

Glad to have been of assistance.

I started flying RC helis back in 1985 (wow 23 years, seems like just a few years ago).

And the main thing I have learned n all that time, is that a proper set-up (mechanical and electrical) is the most important "component" in ANY heli.

A poorly set-up $6000.00 heli combination can easily be out-flown by a properly set-up $1000.00 combination.

And that it is so easy to blame the heli, when it is a set-up problem with the motor, or the throttle to collective set-up, or the gyro set-up etc.

IMHO knowledge in how to do all of this is more important then the machine and its' components.