General HOW-TO Setup helicopter FBL head - Align 3GX / Spektrum - by Marius S

[enerko]

Hi Marius,

It is really a great job. As I am going to build an Align 500 DFC heli your 3gx Dir setting information is of much help to me.
I have some questions about 90 degree servo horn adjustment.
-Before assembling the body frame I want to do 90 degree servo horn setting, for the elevator servo is not easy to screw in the inside of the body frame.
So, can I do 90 degree servo horn setting on the work bench separately? I mean I just finish servo setting and stop, disconnect the power and later install the servos onto the frame to make swashplate level.

-After servo setting and before disconnect the power do I have to push some button in 3gx in order to save memory or just cutting the power is OK?

-What about the swash mix in the Tx? Is it 1 servo 90 degree or 3 servos 120 degree? In the manual no swash mixing, but many people say 3 servo 120 degree.
It's a bit confusing!

Thanks

 

[Tony]

Cleaned up your triple post, not sure why that happened lol.

to answer your question, since your servos are square to the links (aileron and pitch are standing vertical and elevator is laying horizontal), then yes, you CAN set them up to 90º to the body of the servo. Just remember that you need to remember what servo is what. Once you set the servo arms, and they are a perfect 90º, don't ever touch the subtrim or trim again. That is where the gyro will come in to play.

As for the swash setting, it will be set on 3 servo 120º swash. When they say mixing, they are talking about mixing say aileron into the elevator, or missing the pitch into the tail and so on. Hope this helps.

 

[stokke]

Hi Marius,

It is really a great job. As I am going to build an Align 500 DFC heli your 3gx Dir setting information is of much help to me.
I have some questions about 90 degree servo horn adjustment.
-Before assembling the body frame I want to do 90 degree servo horn setting, for the elevator servo is not easy to screw in the inside of the body frame.
So, can I do 90 degree servo horn setting on the work bench separately? I mean I just finish servo setting and stop, disconnect the power and later install the servos onto the frame to make swashplate level.

-After servo setting and before disconnect the power do I have to push some button in 3gx in order to save memory or just cutting the power is OK?

-What about the swash mix in the Tx? Is it 1 servo 90 degree or 3 servos 120 degree? In the manual no swash mixing, but many people say 3 servo 120 degree.
It's a bit confusing!

Thanks

Thank you for your feedback.

Yes, the servos can (and should) be 90'd outside of the helicopter on the workbench. This is also depicted and described in my guide. Please carefully read the instructions before you start working, and do not skip parts - read from the top.

After you have set 90° on each of the three servos (on the workbench), then labeled them (so you remember where they are supposed to be mounted), your transmitter will have stored these settings. It is safe to power off the transmitter and helicopter.

As Tony stated, you are going to choose 120° swash in your transmitter settings.

Again, please read the instructions carefully.

Good luck buddy!

ps. be sure to be safe when doing this, disengage the motor if possible.

 

[enerko]

Thank you for your feedback.

Yes, the servos can (and should) be 90'd outside of the helicopter on the workbench. This is also depicted and described in my guide. Please carefully read the instructions before you start working, and do not skip parts - read from the top.

After you have set 90° on each of the three servos (on the workbench), then labeled them (so you remember where they are supposed to be mounted), your transmitter will have stored these settings. It is safe to power off the transmitter and helicopter.

As Tony stated, you are going to choose 120° swash in your transmitter settings.

Again, please read the instructions carefully.

Good luck buddy!

ps. be sure to be safe when doing this, disengage the motor if possible.

Thanks for the valuable information, Marius and Tony!

I will select 3 servo 120 degree swash setting in my Tx and as you say I will mark each servo not to be mixed.

Cheers,

Glen

 

[wachter]

super video, maios est ce la meme chose avec dx7s et 3 G

 

[Tony]

I do apologize, but none of us (that I know of) speak French on here.

 

[billryalls]

it helped me out a TON! THANKS!

 

[Mac]

Marius, what a great article!

I appreciate the time and effort you put into this article. The photos were a tremendous help. Like they say, 'A picture is worth a thousand words'. Also, the words you added to the photos certainly cleared many things up for me.

Thanks,
Mac

 

[stokke]

Marius, what a great article!

I appreciate the time and effort you put into this article. The photos were a tremendous help. Like they say, 'A picture is worth a thousand words'. Also, the words you added to the photos certainly cleared many things up for me.

Thanks,
Mac

It's my pleasure Mac. Glad it was helpful

 

[mainly]

hi, i have a few questions...

just read the complete setup guide, and it was very well done, the most complete ive seen so far.

just wondering what difference it makes that you label the servos, if they've all been leveled to 90% anyway?

as well, i assume before we start on this setup that our receiver should be powered on, bound and hooked up?

and is there anything else we need to do on the 3gx "before" we start this procedure? i thought i read somewhere you have to BIND to the 3gx as well?

 

[Tony]

It's imperative that you 90º the servo arms to the linkage rods. That way you have equal travel in both directions.

 

[mainly]

It's imperative that you 90º the servo arms to the linkage rods. That way you have equal travel in both directions.

yeah i know that, but the question was why you need to label them, if they're all the same(all 90 deg)

 

[Tony]

Because each of the servos is going ot have a different value to get to the center point. Your pitch servo (left front) might have a 23 sub trim, but your aileron servo (right front) might have a -15 sub trim.

 

[pvolcko]

Also, unless you're dealing with a goblin or 700X or something else with a new fangled servo mount pattern, you're going to end up with at least one of them having the horn on the other side and it will end up needing to be reversed (or the proper swash reversal pattern picked out, or on the 3GX use the swash mix function in the Tx to reverse one or more of pitch, ail, or ele). If you don't know from the start what servo goes in which position, you will not know which one(s) have to have the horn mounted reversed.

 

[mainly]

Because each of the servos is going ot have a different value to get to the center point. Your pitch servo (left front) might have a 23 sub trim, but your aileron servo (right front) might have a -15 sub trim.

i still dont get it. at that point, all that was done was the arms placed on so that they were at 90 deg, no? as far as the servo is concerned, all that has been done is a servo arm placed on it. and theyre all at 90, no subtrim has been applied to the servo as of yet, has it?

 

[murankar]

Okay look at the Gaui X3 fir instance. The servo layout is almost standard for the most part. In fact it's almost the same as a t-rex 450 pro. What's different is the direction the arms face.

When I center the servo arms it has to be for a very specific location. If I do not mark or some how identify what servo is what then I could Jack up the setup.

Centering a servo arm does not mean it's going to be universal on any on kit in any location. You could install One arm 90° outboard then take it off and install it inboard on the same servo and it will be off.

Sent from my LG-E980 using Forum Runner

 

[stokke]

i still dont get it. at that point, all that was done was the arms placed on so that they were at 90 deg, no? as far as the servo is concerned, all that has been done is a servo arm placed on it. and theyre all at 90, no subtrim has been applied to the servo as of yet, has it?

The example helicopter used in my guide, the T-Rex 450, has both the PITCH servo and the ELEVATOR servo pointing in the same direction. This may cause you to swap them around when installing them on the model, which may lead to applying wrong sub trim settings on these servos.

Example: If you were to apply a value of -16 on the PITCH servo, and a value of +3 on the ELEVATOR servo during the initial "90'ing" of your servos, then by mistake connect the intended PITCH servo to the ELEVATOR-port and vice verca, you'd apply the wrong amount of sub trim to these servos - leading to the servos not being 90°.

The outcome of such a mistake will result in a improper head setup - and the helicopter will not fly very well (most likely it will end in a crash if the user is a beginner).

___

If you are referring to the very first step, which comprises of only putting on the servo arms - then yes, it would not matter where you connect the PIT and ELE servo. But for most first time builders it can be helpful that a guide is straight forward and not up for interpretation - as this may often lead to confusion. This is the reason I am telling builders to keep track of their servos from the very beginning.

Thanks for reading my guide

 

[mainly]

___

If you are referring to the very first step, which comprises of only putting on the servo arms - then yes, it would not matter where you connect the PIT and ELE servo. But for most first time builders it can be helpful that a guide is straight forward and not up for interpretation - as this may often lead to confusion. This is the reason I am telling builders to keep track of their servos from the very beginning.

Thanks for reading my guide

yes i about the servos pointing in the correct directions, i see your point.

where i was confused was - from the point right before you said...

"After this point the servos function is defined"

the two servos that are pointing in the same direction, why could you not interchange those??

thats what i was wondering about.

- - - Updated - - -

btw, im thinking about ditching the 3gx afterall, and getting the spektrum AR7200BX instead. since i havent started on the electronics or mechanical setup.

the manual seems to be so much more user friendly, (actually written in ENGLISH) and i might actually be able to follow it.

plus, with the reciever and gyro in one, less wires, simpler , etc

any opinions on this choice?

- - - Updated - - -

btw, im thinking about ditching the 3gx afterall, and getting the spektrum AR7200BX instead. since i havent started on the electronics or mechanical setup.

the manual seems to be so much more user friendly, (actually written in ENGLISH) and i might actually be able to follow it.

plus, with the reciever and gyro in one, less wires, simpler , etc

any opinions on this choice?

- - - Updated - - -

not sure what happened with my last post, sorry

- - - Updated - - -

ok, are you kidding? this - - - Updated - - - thing is so annoying, why is this here? lol

- - - Updated - - -

ok, are you kidding? this - - - Updated - - - thing is so annoying, why is this here? lol

 

[Tony]

The "updated" is a program in the forum that keeps replies in it's own post until 20 minutes after you are done posting. Keeps from creating a very long thread when teh same person is posting. As for the double posting, as I stated in your PM, I'm working on the issue, just not having much luck.