FBL Gyro 550x Beastx Issue

[Rowdy]

I recently switched my esc from a talon 90 to the new spektrum avion 100a. my style has changed over the last couple of years and recently ive always been landing with the overcurrent warning and a talon 90 that was hot enough to cook on lol. So i picked up the spektrum 100a which i swapped out and installed. Keep in mind before i Changed the esc the machine was flying locked in and excellent. now after the esc change, the tail barely holds in normal mode and blows out. Not to mention when i switch into Idle up mode it has a pretty quick wag to it. and as it sits now is unflyable. so to troubleshoot i enabled the gyro on the 3 position switch on my dx8 (i also noticed it said it was "inhibited" before i enabled it) and so i started with 30% gain then took off and landed until i reached 14%. i figured it was a gyro gain issue!? but no matter the value on my radio i turned it too its like im not effecting the model at all. Setup is and was always a weakpoint for myself as there is nobody near me that flys helis, so i have had to learn everything myself. This 550x was my first larger size heli i had, and the person who had helped with the initial setup passed away not too long ago. So i have the passion to never give up and keep learning but i really dont know what to do......any advice would be so appreciated and helpful. thank you all for your time to whomever reads this.

Trex 550x, dx8 g2, ar7210bx, spektrum avion 100a

 

[Smoggie]

When you swapped the ESC, you didnt change anything else.. correct? If that's the case then stop messing with FBL settings because that cant be the problem, it must be something related to the ESC.

My guess is that you need to set the ESC up in Governor mode and/or setup proper throttle curves in the transmitter. Castle ESC's have a rather unique governor 'Set RPM' setup that requires throttle curves of 30%, 70% and 100% in the three flight modes. This wont work with any other brand of ESC.

So what I;m thinkiing is that the guy who set it up for you probably used the 30% curve for your 'normal mode'... which is now with the new ESC giving too low RPM so the tail wont hold... And 100% for your idle up with with the new ESC is giving too high RPM, so the tail wags.

So the steps to take:

1. Read the ESC manual!
2. If not done already set up the ESC correctly, including setting heli governor mode. Also set BEC voltage to something in the 7.4-8.4V range if using the 550X HV servos.
3. Calibrate ESC end points (should be covered in the manual)
4. Set correct throttle curves in Tx***

***For most ESCs throttle curves for governor mode would look something like:
Normal mode*: 0-65-65-65-65
Idle up 1: 75-75-75-75-75
Idle up 2: 85-85-85-85-85

*Personally my preference is not to use a 'normal mode' curve (i.e. not use one that starts at 0%) but just start and stop the motor with the throttle hold switch... but I'll leave that option up to you.

 

[leedude1]

Hey Smoggie,

Curious why not the zero 0% start? I use it sort of like an additional guard in case I flip the switch by accident , it doesn't spool up right away and have that little bit of a what if. I use normal just to take off and fly I1 or 2 and landing, ill bring it into a hover and TH to float it down.
Is there a specific reason for no Zero or just preference?

 

[Smoggie]

Hey Smoggie,

Curious why not the zero 0% start? I use it sort of like an additional guard in case I flip the switch by accident , it doesn't spool up right away and have that little bit of a what if. I use normal just to take off and fly I1 or 2 and landing, ill bring it into a hover and TH to float it down.
Is there a specific reason for no Zero or just preference?

A few of reasons:

1. Everyone who uses normal mode that i know has crashed due to forgetting and trying to fly inverted in normal mode
2. It teaches the bad habit of pulling down on collective to stop the motor. This causes problems when you start flying in idle up because you forget to hit 'hold' and pull collective down instead.
3. It makes setup more complex because you have to have a special pitch curve to avoid spooling up with lots of negative pitch

None of these things are 'show stoppers' but as normal mode has no actual advantages I dont see the point. If you want a safety switch simply program another switch to work as throttle cut, so both 'Hold' and 'Cut' switches need to be moved to spool up.

 

[leedude1]

Hey Smoggie, yeah ok I can see how that may happen. I know I've crashed in the sim a few times relaying to your first point, so makes sense.