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Old 02-14-2021, 05:04 PM   #1 (permalink)
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Default Swashplate leans to the right on spooling up!! SOLVED

I'll let the video explain the issue.

Once took off, it flies fine but I have to be careful on taking off. It didn't happen before. Calibration didn't help.

Thanks

FC6250HX issue (0 min 23 sec)


FC6250HX issue clip 2 (0 min 24 sec)

Last edited by tanasit; 02-19-2021 at 04:39 AM..
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Old 02-14-2021, 06:54 PM   #2 (permalink)
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If you take the head off and disconnect the motor, does the swash track correctly with collective input?

You say it flies fine after take off - does the model track straight up and down with pitch pumps?
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Old 02-14-2021, 08:51 PM   #3 (permalink)
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Quote:
Originally Posted by wjvail View Post
If you take the head off and disconnect the motor, does the swash track correctly with collective input?

You say it flies fine after take off - does the model track straight up and down with pitch pumps?
With no motor connected, the same thing happens!

I did try pitch pump ealier and it was fine, quick climb and straight up too.

FC6250HX issue clip 3 no motor connected (0 min 54 sec)
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Old 02-15-2021, 12:53 AM   #4 (permalink)
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That is curious behavior. Can you use the "Servo Monitor" function on your transmitter and confirm the cyclic servos are moving in unison? It would be nice to confirm that your transmitter isn't sending a roll command with collective. Because there is no roll command when you move the collective quickly I would assume there isn't but it is easy enough to check.
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Old 02-15-2021, 07:07 AM   #5 (permalink)
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Quote:
Originally Posted by wjvail View Post
That is curious behavior. Can you use the "Servo Monitor" function on your transmitter and confirm the cyclic servos are moving in unison? It would be nice to confirm that your transmitter isn't sending a roll command with collective. Because there is no roll command when you move the collective quickly I would assume there isn't but it is easy enough to check.
I did that already because I thought only servo #3 (right aft) was acting weird but they all work as you said "unison". I also test them 1 at a time to see if one moves linearly and they do.

I have one more idea to test, stay tune.
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Old 02-15-2021, 07:52 AM   #6 (permalink)
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I would start the program from scratch again. I'm trying to remember what the cause was when I had something like this in the past. I it was the type of CCMP selected. I was using 120 instead of normal??


I may be off base. Start with a fresh model memory too. I had some mixing that I didn't intend and was messing things up.



I had a Blade 330s with that controller and I would have to spool up and lift off quick so it wouldn't have a chance to eat the dirt. Landing too. I had to touch down and throw TH and dump to negative collective to keep if from eating dirt. That is what pushed me over the edge and led me to sell it. I hated have it eat dirt for no fault of my own and fixing that tiny thing with the half shell frame that broke all the time and was a pain to fix... Gone now.


I'm using the MSH Brain2 now on my 700's. I had a bad experience with the BeastX controllers as well with upgrading to PRO, getting support and logging into their service not to mention getting rescue mode to work! I'm very happy with the Brain2!

Last edited by littledog28; 02-15-2021 at 07:55 AM.. Reason: add more notes
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Old 02-15-2021, 04:05 PM   #7 (permalink)
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Do you have Safe “on” on that flight mode? I believe the FC6250HX comes with a default of 450 (4.5 or 45 degrees) for the Roll value in FwdPrg>Safe>Attitude menu. Supposedly this is to compensate the tail rotor force that could make the heli flip on it’s left side when taking off (according to Horizon Hobby). I have it on 0 for my helis when Safe’s on.


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Old 02-19-2021, 04:32 AM   #8 (permalink)
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Quote:
Originally Posted by Fusion View Post
Do you have Safe “on” on that flight mode? I believe the FC6250HX comes with a default of 450 (4.5 or 45 degrees) for the Roll value in FwdPrg>Safe>Attitude menu. Supposedly this is to compensate the tail rotor force that could make the heli flip on it’s left side when taking off (according to Horizon Hobby). I have it on 0 for my helis when Safe’s on.


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I believe that the limit angle in the SAFE mode. But the one that will compensate for the tail rotor torque is the Hover Throttle, whose defaylt is 65%.
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Old 02-19-2021, 04:39 AM   #9 (permalink)
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SOLVED:

Check these setting:
The Throttle value (hover throttle) in the FP (Forward Programming) which is default at 65.

Next check your throttle curve in ALL flight modes, in particular the mode that you always use to take off.
The number must NOT be higher that 65 (as mentioned above in FP)!!

Or you can disable the take off hover compensation (swashplate tilt) , by temporary set the Throttle value in FP much higher, say 80 in place of the default 65.

Note also that once you set the swash Sub Trim in FP, get out of FP with throttle stick on the BOTTOM always!!!
Next go to Hold mode, center throttle stick and look at the swash, if it’s not level, say tilt to the left.
You have to look at the servo arms of BOTH roll. Choose to adjust the one that is MORE off to your eyes by going in to FP and swash Sub Trim.
At this point do not worry if the swash is not level.
Next get out of FP and repeat the above.

It will be easier if the swash needs elevator setting because you need to adjust only 1 servo.
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Old 02-19-2021, 04:43 AM   #10 (permalink)
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Have you got any form of 'self levelling; (SAFE etc) enabled? if so try it without and see if it still does it.

Self levelling systems can cause this because they are calibrated to make the heli hover without drift. This means that they are calibrated for a slight right 'lean' of the heli (due to translating tendency). If activated on the ground self levelling tries to lean the heli to the right because that is the calibrated position.
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Old 02-19-2021, 01:09 PM   #11 (permalink)
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Quote:
Originally Posted by Smoggie View Post
Have you got any form of 'self levelling; (SAFE etc) enabled? if so try it without and see if it still does it.

Self levelling systems can cause this because they are calibrated to make the heli hover without drift. This means that they are calibrated for a slight right 'lean' of the heli (due to translating tendency). If activated on the ground self levelling tries to lean the heli to the right because that is the calibrated position.
I did mention that in post #8 above already.

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Old 02-23-2021, 10:02 AM   #12 (permalink)
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Quote:
Originally Posted by tanasit View Post
SOLVED:
Or you can disable the take off hover compensation (swashplate tilt) , by temporary set the Throttle value in FP much higher, say 80 in place of the default 65.
I believe that if you set the hover throttle to 80 you will actually make sure it's always enabled instead of disabled. Putting it somewhere between 0-35 will actually disable it, i.e. when your ESC won't spool up the motor below 40%.

If I understand correctly you are trying to say that once you "break through" the hover compensation, the swashplate will roll. So when you increase the hover throttle you'll never break through and thus the rolling won't happen. That would mean that everyone who takes off in Safe should have this effect occurring, because everyone would need more throttle (i.e. 65%) than the set hover throttle (i.e. 55%).

Brian, can you shed a light on this? When I look at the Youtube FC6250HX series with Tom Cogswell he says specifically that the FwrdPrg>Safe>Attitude>Roll value is designed to compensate for not flipping over at take off. He also says the hover throttle is designed to set a limit to which Safe will intervene more to keep the heli more stable when taking off and hovering.
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Old 02-24-2021, 10:16 AM   #13 (permalink)
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From the manual;
.................
19. Select Throttle->Hover This setting is the throttle point where your model hovers in normal mode, mainly during takeoff and landing. The flight controller applies special anti roll over algorithms at or below the throttle setting, helping to make takeoffs and landings easier.

The Stunt 1 and Stunt 2 throttle curves should be above the hover throttle setting to ensure the roll over mitigation is disabled in flight.

During the initial setup, you can set Throttle->Hover to a high value and test the model. Once the throttle setting is determined for hovering in normal mode, set the Hover Throttle value.
.................

I am not aware of a "FwrdPrg>Safe>Attitude>Roll" parameter.

There is a FwrdPrg>Safe>Attitude>Roll Trim parameter and that is the attitude trim for the model. For example if your model is sliding/translating to the left in a hover in stability mode with no wind then increase the Attitude->Roll Trim value. If sliding/translating to the right in a hover in stability mode.....then decrease the value.

When taking off in stability mode it is necessary to make inputs to keep the disc level with the surface you are taking off from and the controls should quickly transition back to center after lift off. The opposite applies to landing.
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Old 02-24-2021, 09:20 PM   #14 (permalink)
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Quote:
Originally Posted by Fusion View Post
I believe that if you set the hover throttle to 80 you will actually make sure it's always enabled instead of disabled. Putting it somewhere between 0-35 will actually disable it, i.e. when your ESC won't spool up the motor below 40%.

If I understand correctly you are trying to say that once you "break through" the hover compensation, the swashplate will roll. So when you increase the hover throttle you'll never break through and thus the rolling won't happen. That would mean that everyone who takes off in Safe should have this effect occurring, because everyone would need more throttle (i.e. 65%) than the set hover throttle (i.e. 55%).

Brian, can you shed a light on this? When I look at the Youtube FC6250HX series with Tom Cogswell he says specifically that the FwrdPrg>Safe>Attitude>Roll value is designed to compensate for not flipping over at take off. He also says the hover throttle is designed to set a limit to which Safe will intervene more to keep the heli more stable when taking off and hovering.
No you have it wrong and I just tested to confirm it and as Brain said from the manual which clearly states,"“During the initial setup, you can set ThrottletHover to a high value and test the model. Once the throttle setting is determined for hovering in normal mode, set the Hover Throttle value.”

To disable this, set the ThrottleHover to HIGH value.

I traced back to what I did and found out that I chnaged the main pinion gear to from 21T to 19T so that I can fly at lower head speed. And to compensate for the power required with 2 teeth difference on the gear, I bumped up my throttle curve from 0,65,65,65,65 to 0,70,70,70,70 wheereas the Hover setting in Forward programming (FP) stays the same at 65 and that's my mistake.

Now I remember that I will NOT set the numbers in my throttle curve any HIGHER than the Hover value in the FP.
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