600 TREX 550E Rudder servo not working right

[Merv49]

I'm trying to set up the rudder servo on my TREX 550E DFC and I've watched all the setup video's and gone step by step to get the right direction and responses from the servo but when I'm done with all that I found that my rudder servo is not acting properly for some reason. What it's doing is not returning to center after I move the stick full travel one way or the other. I plugged in another digital servo to make sure the installed servo wasn't bad and the same problem exists. The servo won't center properly and goes where it wants to go as far as centering goes and will still go to end of travel and stick there in either direction. I'm new to this but have no idea what is causing this behavior. Any help would be greatly appreciated.

Merv

 

[Derek]

I saw that you posted this in another thread. I'll keep your thread here and I'll delete the other one.

If you are in heading hold mode, the tail slider will not return to center (while the heli is stationary on the ground). In rate mode, the tail will recenter. Can you move the tail from the left to the right and see if the tail slider is moving in the correct direction? If so, then you should be "good to go".

 

[Merv49]

I saw that you posted this in another thread. I'll keep your thread here and I'll delete the other one.

If you are in heading hold mode, the tail slider will not return to center (while the heli is stationary on the ground). In rate mode, the tail will recenter. Can you move the tail from the left to the right and see if the tail slider is moving in the correct direction? If so, then you should be "good to go".

Which mode should I be in. This is my first helicopter and I don't know how I got in heading mode. The tail slider moves in the right direction so I should leave things as they are?

Merv

 

[Derek]

Rate Mode is mostly for "scale" fliers. Heading Hold mode would, most likely, be what you are looking for. Heading hold mode will keep the tail inline with the nose. What radio equipment are you using? I have the DX8 and Rate Mode is in the gyro settings that is anything below 0%. Heading Hold mode is any percentage above 0%. When I was using my DX6i, I'm thinking that Rate Mode was below 50% and Heading Hold mode was above 50%.

 

[murankar]

That is correct for the dx6i. A good starting point is 65% on the dx6i for hh mode. Rate mode is 35% fir starters.

Sent from my LG-E980 using Forum Runner

 

[Lee]

When in Head hold mode on the bench, if you give the heli a command to turn then re centre the stick, the gyro i trying to move to the new heading. Because its stationary it keeps trying to turn the heli. That is why it doesn't return to centre.

If this i really your first heli, then make sure to get some help from someone more experienced for your first flight. A 550 is not a toy, and can and will do some damage.
You will love it though, fantastic heli.

Check my RC tips and trick for gyro/servo help, below my post.

 

[Merv49]

Rate Mode is mostly for "scale" fliers. Heading Hold mode would, most likely, be what you are looking for. Heading hold mode will keep the tail inline with the nose. What radio equipment are you using? I have the DX8 and Rate Mode is in the gyro settings that is anything below 0%. Heading Hold mode is any percentage above 0%. When I was using my DX6i, I'm thinking that Rate Mode was below 50% and Heading Hold mode was above 50%.

I/m using the Futaba 8FG system with the S-Bus. Thanks for your response.

Merv

- - - Updated - - -

When in Head hold mode on the bench, if you give the heli a command to turn then re centre the stick, the gyro i trying to move to the new heading. Because its stationary it keeps trying to turn the heli. That is why it doesn't return to centre.

If this i really your first heli, then make sure to get some help from someone more experienced for your first flight. A 550 is not a toy, and can and will do some damage.
You will love it though, fantastic heli.

Check my RC tips and trick for gyro/servo help, below my post.

Thanks. I'm try to learn as much as possible before taking to the air and I have a couple experienced guys to give me a hand when I'm ready to go. Trying to spread out my questions so I don't bug them to much. LOL There is a wealth of info on the net and I'm trying to soak it all in. It's like learning a new language but I'm getting there. Thanks for your help.

Merv

 

[murankar]

Then bug us for the info. That's why we are here. Just remember at some point you may need them to assist so build a report with them.

Sent from my LG-E980 using Forum Runner

 

[Merv49]

Then bug us for the info. That's why we are here. Just remember at some point you may need them to assist so build a report with them.

Sent from my LG-E980 using Forum Runner

One more question. I'm told that the Talon 90 ESC is already programmed from Align. Is that so or do I need to get the adapter and program it somehow, now or in the future. I talked to Castle and they said Aligh has the ESC already programmed so they don't include the adapter when you buy the helicopter which saves them money.

Merv

 

[murankar]

get the adapter if they gave you the coupon card. if they didnt then ask someone on here for a coupon, I think a couple people may have one on hand. Anyhow if not then gop ahead and buy it. It is well worth the 25 or so bucks that it costs.

As for being programed it just maybe programed, it better to double check just to make sure.

 

[Merv49]

get the adapter if they gave you the coupon card. if they didnt then ask someone on here for a coupon, I think a couple people may have one on hand. Anyhow if not then gop ahead and buy it. It is well worth the 25 or so bucks that it costs.

As for being programed it just maybe programed, it better to double check just to make sure.

Thanks. I have ordered it.

- - - Updated - - -

The directions for the 550 show the CG as being 60 degrees either nose up or nose down, either tail or nose heavy. Coming from airplanes this is strange to me. How critical is the cg on a heli? What is preferred, nose or tail heavy and does it really not make a difference?

 

[danhampson]

The CG is important as incorrect CG will use some of the travel of the servos as the FBL controller will be trying to correct all the time, this intern puts more strain on the servos as they are having to work all the time to correct the CG.

The CG test in the Align manual is the correct method to find if your CG is out or not, and i personally do the the CG test with the main shaft pointing to the left and then to the right to allow for the OWB.

I have also checked the CG by picking the heli up by the blade grips (main blades off) with one finger under each grip to allow the heli to pivot and watch for the nose/tail dipping, I have found that this works quite well on smaller helis (< 500) but as i dont own any thing above a 500 i dont know if the size/weight would be an issue with a bigger bird with this method.

 

[Merv49]

Would you say that getting as close to zero degrees on the balance is better? Neither nose or tail heavy?

 

[danhampson]

Yes i would try to get it as close as possible by playing with the position of the battery, The closer the CG to neutral the better, in an ideal world with no wind at all and a perfect CG the FBL controller and servos would do little to no work in a stationary hover

 

[Merv49]

Thanks

Merv