Trex 700 3gx v3.0 tilt back issues...

[tsangbou]

Trex 700e v2 3gx v3.0 tilt back issues...

Please help me guys....
TX dx8, All links are correct and 90deg servos.

Prior to setting my at DIR I made sure my pitch curve is at linear 0,25,50,100 with dual rates 100%

I have leveled swash at DIR and checked 0-100 percent is perfectly leveled.

But why when I’m out of dir mode when I lower my pitch my elevator tilts back around 3mm making the heli drift backwards?

[Delarado]

Does it move more than the other servos? you didnt set collective/elevator/aileron values using servo endpoint values rather than swashplate values by accident did you?

[tsangbou]

Does it move more than the other servos? you didnt set collective/elevator/aileron values using servo endpoint values rather than swashplate values by accident did you?

Thanks for your reply. on my dx8 i had to reduce to elev 90% end points to see it level at DIR. ive not set swash mix yet. i was just checking to see if swash is level outside DIR. Then supposed to set 8 deg cyclics thru swash menu. The reason im doing this is last time when i completed the setup the heli was drifting backwards so this is a new setup.

[tsangbou]

Thanks for your reply. on my dx8 i had to reduce to elev 90% end points to see it level at DIR. ive not set swash mix yet. i was just checking to see if swash is level outside DIR. Then supposed to set 8 deg cyclics thru swash menu. The reason im doing this is last time when i completed the setup the heli was drifting backwards so this is a new setup.

yes the elev is moving 3mm further down when i pull down lowest pitch. its perfectly level during DIR

[DaveJones]

Trex 700 3gx v3.0 tilt back issues...

Not an expert by any means but why have you adjusted the end points to get the swash level? I would leave the end points at 100% and adjust the links then sub trim to get the swash completely level. Then move on to the swash mix.

Do a google search for "Freddy can fly" he had some videos I found useful when setting up my 3GX.

I would probably complete all the DIR setup before worrying about the swash being level in flight mode. Just get it spot on in DIR, I found my less than perfect setup caused my heli to fly like a donkey and I had to repeat a couple of times.

Cheers Dave

[coolice]

Hey.

The 3GX instructions state that you must not adjust the ATV values, leaving them at the default 100/100 state.
Unlike a flybarred model you cannot use your ATV's to level the swashplate at its extremes of travel. Some FBL units allow this to be done via their setup, but not the 3GX.

Go back into DIR mode and remove all subtrims and return your ATV's to 100/100.
Now put your pitch to mid stick and level your servo arms at 90 degrees, take your time at this stage as any inaccuracys here introduce an unlevel swashplate at its extremes.
Try to limit how much subtrim you use, swap servo arms around until you find the best position for each one to limit the amount of subtrim used.

The Align instructions are very good, follow them through step by step and you'll be good to go.
.

[tsangbou]

Not an expert by any means but why have you adjusted the end points to get the swash level? I would leave the end points at 100% and adjust the links then sub trim to get the swash completely level. Then move on to the swash mix.

Do a google search for "Freddy can fly" he had some videos I found useful when setting up my 3GX.

I would probably complete all the DIR setup before worrying about the swash being level in flight mode. Just get it spot on in DIR, I found my less than perfect setup caused my heli to fly like a donkey and I had to repeat a couple of times.

Cheers Dave

The reason i had to reduce the travel of the elev is both up and down throws over shoots the other two servos.

ive seen Freddy can fly vids. i think ill go back and re watch them again.

[DaveJones]

Trex 700 3gx v3.0 tilt back issues...

Assuming the servos are the same type have you got the same length servo arms? You could maybe look to move the servo ball in a hole to reduce the effective throw.

Won't the swash mix setting prevent the servos going full throw anyway? That said all three need to be traveling the same distance proportional to the stick movement. The Freddy vid's have a piece about using the swash level tool to check swash travel is level through the pitch range which might be useful

[tomatwalden]

The reason i had to reduce the travel of the elev is both up and down throws over shoots the other two servos.

ive seen Freddy can fly vids. i think ill go back and re watch them again.

Apologies as this is teaching granny to suck eggs - but you do have the exact same servos in the cylics ?

[tsangbou]

Apologies as this is teaching granny to suck eggs - but you do have the exact same servos in the cylics ?

haha yes they are the same servos that came with the kit ds610. the links are measured exactly the same length. i will re look again tonight. may be its just me doing something wrong with this 700. Both my 450 and 550 flies like on rails and i did all setups by myself.

Tonight Ill take note of everyones advise here and redo everything again and see.

Thanks everyone.

[Delarado]

YOu dont need to worry about the swash being level at the extremes of travel. IF its not, the heli will rotate. If the heli rotates (Without you commnding it to) The 3gx should counteract it. Remove your endpoint changes and itll all work fine im sure.

[tsangbou]

A couple of days ago I was trying again to reset my swash with all 3 servos endpoints 100%... (with DIR)
What I'm confused is why is my elev servo at zero pitch is perfect level and at max or min pitch it over shoots around 2-3 mm on each end points? outside DIR mode its even worse.. 3-4mm!!!
The elev arm is set perfectly as per manual and the other two is also set as per manual.
All 3 servo is subtrim to 90deg. all 3 is under 20 clicks. all 3 servos are ds610.

[tourerjim]

A couple of days ago I was trying again to reset my swash with all 3 servos endpoints 100%... (with DIR)
What I'm confused is why is my elev servo at zero pitch is perfect level and at max or min pitch it over shoots around 2-3 mm on each end points? outside DIR mode its even worse.. 3-4mm!!!
The elev arm is set perfectly as per manual and the other two is also set as per manual.
All 3 servo is subtrim to 90deg. all 3 is under 20 clicks. all 3 servos are ds610.

Are you using servo wheels if so there's no need to use subtrim as there will be a 90* point on them also are you using swash leveling tool or something else.
If your using swash tool you need to check for servo interaction so in dir mid stick servo's 90* move stick to full again check swash then full neg if your getting interaction you could be out with one one of your servo's check this first.

[tsangbou]

Are you using servo wheels if so there's no need to use subtrim as there will be a 90* point on them also are you using swash leveling tool or something else.
If your using swash tool you need to check for servo interaction so in dir mid stick servo's 90* move stick to full again check swash then full neg if your getting interaction you could be out with one one of your servo's check this first.

Thank make, yes i'm using the stock wheels and swash tool. I'm about to have a look again. I'll measure if rods are too long or short. Ive only measure the links and forgot to double check the rods on the ail/pitch servos.

[tsangbou]

Are you using servo wheels if so there's no need to use subtrim as there will be a 90* point on them also are you using swash leveling tool or something else.
If your using swash tool you need to check for servo interaction so in dir mid stick servo's 90* move stick to full again check swash then full neg if your getting interaction you could be out with one one of your servo's check this first.

just checked all lengths are exactly as per manual.
Do you thnk there might be something wrong with my 3gx?