CCPM using a Futaba 6EX

[khaled_abobakr]

Edit Debian Dog
(9 threads merged to one problem)
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As I'm trying to setup my CCPM Trex 450 S CF using a Futaba 6EX 2.4 GHZ and 3 hitec 65MG servos ,, I noticed why I can't get all servo horns at 90 >> that is because each time I try to trim a certain servo all others move also ...

What could be wrong please help me coz I'm really really worried >> is my 6EX defected .... ??

Any help is greatly appreciated

During the setup of my T-REX S CF helicopter

1- Phoenix 35 ESC
2- SportBEC 6V External battery eliminator circuit
3- No motor is connected to the ESC
4- No Gyro connected which will be channel 5
5- No tail servo connected which will be channel 4
6- 3 X Hitec servo HB-65MG metal gear micro analog servos
7- Thunder power 3S 11.1 V 2100 mah


Each time I want to trim channel 1 servo I notice that also channel 6 servo moves
when I trim channel 2 I notice that channel 1 and channel 6 move too

when I tried triming channel 3 or channel 4 and they r not connected to any servos just blank channels I noticed that channle 1 and channel 2 and channel 6 do not move ( works correct)

Could u please help me coz I'm really worried what's wrong is my radio defected ??

yes I do

The problem is uring the setup of my T-REX S CF helicopter

1- Phoenix 35 ESC
2- SportBEC 6V External battery eliminator circuit
3- No motor is connected to the ESC (ESC is not armed yet)
4- No Gyro connected which will be channel 5
5- No tail servo connected which will be channel 4
6- 3 X Hitec servo HB-65MG metal gear micro analog servos
7- Thunder power 3S 11.1 V 2100 mah
8- swash plate is set to 3-S
9- EPA and D/R expo are all defaults - No REVO
10- pitch curves and throttle curves are set to default
11- idl- throttle and idle pitch r set to default


Each time I want to trim channel 1 servo I notice that also channel 6 servo moves
when I trim channel 2 I notice that channel 1 and channel 6 move too

when I tried triming channel 3 or channel 4 and they r not connected to any servos just blank channels I noticed that channle 1 and channel 2 and channel 6 do not move ( works correct)

Could u please help me >> I'm so worried

[WayneBrown]

dude, do NOT post multiple times across many forum sections.
It upsets the animals, and will likely result in you getting flamed from the members instead of help.

[DavidH]

That is how 120 deg CCPM works. It is 3 servos working together to give the command needed. So for example if the swash plate is tilted to the rear a little. You push the trim next to the elevator stick. When the trim input is given, this moves the rear servo up, and the two front servos move down some. It takes this interaction between the three servos to give the correct command.

Now to your problem. The 6EX does not have sub trims. So the best you can do is to have the elevator and aileron trims ( neutral) exactly centered. Then keep trying servo wheels in different positions on each servo till you get it like you need it. The servo wheels are splined, so when you rotate them, they will give a different position each time. You can rotate them till you find the perfect position for each one. Takes a few minutes to do this, but well worth the effort.

David

[TheJackal]

I'm a noob myself and I will be setting my 6EX myself this weekend.
But to me it sounds like you are trimming aerilon and elevator. Aerilon will make both front servos move and elevator will make all 3 move (the front will move the opposite way to the back).
You need to find the setting to trim a lone servo. Download Finless' videos for servo/CCPM setup or consult the 6EX manual for how to do it.

No doubt someone with more experience will have a bit more info.

[TheJackal]

So does sub trim normally relate to the trim on a particular servo?
So I guess the trick as usual (more so with the 6EX) is to get the mechanical trim spot on

[rstacy]

Originally Posted by TheJackal

So does sub trim normally relate to the trim on a particular servo?
So I guess the trick as usual (more so with the 6EX) is to get the mechanical trim spot on

For CCPM you would like to see subtrim on the channel and not the function. The 6EX does not do this.
As David said, the best and only solution is to have a supply of servo wheels and rotate them until you find the perfect position for each one.

[khaled_abobakr]

do the servo horns of the Hitec HS-65HB fit the the HS-65MG metal gears servos ??

do the new variable futaba servo wheels found in the following link fit the Hitec HS-65MG servo

http://www.readyheli.com/Futaba_Serv...p/futm2010.htm

http://www.readyheli.com/Futaba_Serv...p/futm2030.htm

http://www.readyheli.com/FUTM2400_Fu...p/futm2400.htm

http://www.readyheli.com/FUTM2401_Fu...p/futm2401.htm

[invertmast]

Originally Posted by khaled_abobakr

do the servo horns of the Hitec HS-65HB fit the the HS-65MG metal gears servos ??

do the new variable futaba servo wheels found in the following link fit the Hitec HS-65MG servo

http://www.readyheli.com/Futaba_Serv...p/futm2010.htm

http://www.readyheli.com/Futaba_Serv...p/futm2030.htm

http://www.readyheli.com/FUTM2400_Fu...p/futm2400.htm

http://www.readyheli.com/FUTM2401_Fu...p/futm2401.htm

The hitec wheels from the 65HB will fit the 65MG. the futaba horns will NOT fit hitec servo's

[DavidH]

Here is the spline count for each brand

Futaba 25 splines Only Futaba servo wheels will work

Hitec/RCD 24 splines Only hitec or RCD servo wheels will work

Airtronics/JR 23 splines JR and Airtronics have the same number of splines. So either one will work on the other.

David

[khaled_abobakr]

Thank u very much this helps me a lot

[TheJackal]

So if Hitec servos are 24 splines, does that mean if you rotate the servo horn it doesnt change the alignment as the splines are equally divided every 90 degrees (like when you are trying to get perfect mechanical alignment).

[ozsteel]

Changing the subject little...

In setting up a Logo 500 with a 6EX I have all three servos moving up as throttle increases and all servos working properly when using elevator BUT when using aileron input the servos are working in the opposite direction to that required! How can I get this fixed?

[kaan.gok]

How to get perfect 90degrees on 6EX, I have 4 solutions for you:

1-Get circular wheels, do your setup, and drill your holes at exact locations. (Easy solution)

2-Plug in the servo, find the best fitting spline, open your servo case, relocate your last servo gear (1 tooth). Reassemble, test, if it's not OK, reoen the case and relocate by a one tooth again. (Harder solution, but works with all wheels)

3-Live with the small amount of offset (easiest solution)

4-Buy a better radio (best solution)

[ozsteel]

Originally Posted by ozsteel

Changing the subject little...

In setting up a Logo 500 with a 6EX I have all three servos moving up as throttle increases and all servos working properly when using elevator BUT when using aileron input the servos are working in the opposite direction to that required! How can I get this fixed?

**SOLVED**

After thinking about it for a little while I realised that this is a dumb question - just switch the two offending servos and it all works fine.