Well i think it looks like softmounting those motors made some difference. 
less noise now.. And it flies like a totally different quad now.. More locked in. Plus it seems like i'm even getting longer flight times.
I remember checking my voltage several times because I felt like it took my frsky too long to warn me about low battery.

See traces before and after softmount with similar PID's, maybe someone could take a look at the log in case i'm missing something.
Should have improved.. or is it just me.. wishful thinking that i did something that helped.

https://www.dropbox.com/s/zeictsglvwgf74...5.BFL?dl=0

As I made so many changes now I can't tell which exactly has made things better.. now to see what filters i can turn off and finally fine tune those PID's.
Progress.. at last.

Theres still a bit of jello, but it just sounds and feels better.. But i still have propwash to deal with as you can see..







@UDY
Have you tried swapping out the suspicious motor just to make sure? if you have any spares that is..

My frame has similar connections with those litte metal fillings in the holes.. i dont like it as I can actually move my rear arms no matter how tight i screwed them, and i dont wanna go too tight either,, maybe ill just put a blob of hotglue between the arms and frames before screwing them together,, at least they stay in position

Edit:
Looks like i just won the giveaway from JB
Guess its my lucky day   

@ Sir Brokalot

DUDE, you won Bardwell's giveaway!!! No joke haha First name "Sir Brokalot" I'm like wait.... I know that name!

[edit] sorry had to get that out quickly lol. Congrats man!

To answer your question, yeah first time I swapped that arm's motor with the front right, then changed it for one of my two spares. Thats why I was saying earlier three motors and two ESCs have gone through there, still this desync issue keeps coming back at me.

(14-May-2020, 09:21 PM)udy Wrote: @ Sir Brokalot

DUDE, you won Bardwell's giveaway!!! No joke haha First name "Sir Brokalot" I'm like wait.... I know that name!

IKR, im just as amazed.. and i can confirm its me because i just saw his email
I asked for the Holybro Kopis 3" im stoked!

Posting for the sake of posterity. I'm gonna head out with things set up as follows:

PIDs and filters set up as they were yesterday. That front right arm obviously hasn't arrived yet. It's still got some delamination on the inner arm. Not ideal but not fatal I assume.

I watched Bardwell's BLHeli32 series and set Demag Compensation to high. According to him and his guest there's no downside to this really. I also advanced timing from 23 to 25. Again this shouldn't have a noticeable impact but can help against desyncs.

I also bumped the min throttle to 6.5 (from 6) as a precaution and switched to 4K/dshot300.

I feel really stupid for making so many changes without testing in between but I honestly just can't stand having desyncs anymore. It takes me a good 4 flights to feel even remotely confident in the air again.

@ Sir Borkalot it's odd but I can "feel" that the HD cam is petty high over the roll axis. It's a weird perspective haha! Nice flying and good job on getting things closer to where you want.

@ ronin nice flying! I've practiced endlessly in the sim but my brain just can't compute the rubic cube (and inverted yaw spin). I actually have to concentrate to snap stop flips and stuff, I naturally tend to try and ease them.

My last point... why can't my trees have leaves?! It's may ffs! (Also why doesn't everyone just live in California? It's so nice there haha)

Hey, Congrats on winning JB's giveaway!! Just heard - that's great!

For those of you that didn't hear:

I'm going to start a new thread since this makes no sense and is no longer in the scope of this thread. Though I would share here anyway though:

What is going on in my life...

Note that it's the same motor/arm (#3) that has been giving me desyncs since the beginning, even after swapping motors, replacing with a new one and replacing the esc with a new one...

TBC in the new thread.

In all the times I've seen a motor act like that, it turned out to be the ESC. I bet if you run a continuity test on that ESC it'll come out positive.

Hope you get it worked out man that's such a nice looking build.

(16-May-2020, 01:52 AM)the.ronin Wrote: In all the times I've seen a motor act like that, it turned out to be the ESC.  I bet if you run a continuity test on that ESC it'll come out positive.

Hope you get it worked out man that's such a nice looking build.

You were right. ESC is scrap I think. Rogue solder ball between the FET on the bottom, all the way to the right and its neighbour to the left:



After all this, having to buy another ESC and considering I can easily find PIDs since Steele and VIK openly share theirs, I feel like just tossing this stuff and getting a KISS FC + ESC.

Talk me out of it if necessary...

@UDY
Damn just saw your video, i'm also pretty sure its the ESC somehow. So far i didn't have any problems with the tekko32 but for you it could just be a case of bad luck.
I'm sure you can just get a free replacement for it if you show the supplier your video. Also i really recommend softmounting the motors as well to fix those D-term vibes.

@The.ronin
Thanks for all the help and useful tips. Nice build btw, now I wonder if my single 25v cap is enough, but I do feel my quad is flying allot smoother now.
I will resume to tune it but in the meantime i'm just gonna try to just enjoy flying some more..

In conclusion, in my case the overpowering D was because of external vibration from motors or loose components in the wind.
Things I've changed that seem to have improved things allot are:

Hardware:
- Softmounting motors with rubber pads underneath the motors and between the boltheads.
- Mounted the camera on antivibration standoffs normally used for the FC (Yes, I used smaller standoffs and it just right now)
- Added zipties to secure loose motorwires. (I definitely need to wrap them UDY style.. looks so slick)
- Added half a stick of hotglue to the frame, I'm like a manual 3D printer with hotglue

Software:
- Changed ESC Timing from 24 kHz to 48 kHz
- Changed TPA to 0,60 / 1650
- Disabled D-min
- Disabled Feedforward
- Default filtering according to Joshua's RPM Filter tutorial (Now in process of disabling filters)
- PID's (Higher P values gave P oscillation in FPV Videofeed)


The result:
A Stable locked in little propwashed 4:45 min flight, my longest flight ever on a 1300mah lipo!!
(Added music because I can't stare at buzzing noise for long either..)



Stay tuned, stay filtered and happy flying all!

(16-May-2020, 03:03 PM)Sir Brokalot FPV Wrote: I'm sure you can just get a free replacement for it if you show the supplier your video. Also i really recommend softmounting the motors as well to fix those D-term vibes.

- Added zipties to secure loose motorwires. (I definitely need to wrap them UDY style.. looks so slick)

I'm fairly confident that it broke because of that solder ball, caused by me. I can always try my luck but I'm going to order the replacement anyway since going the "ask the supplier nicely" route never gets resolved quickly.

I've already got soft mounts on the way, should arrive monday or tuesday with the replacement arm.

These are the same size and material as the ones on my quad. I used 6.4mm (1/4") 3:1 ratio adhesive lined heat shrink to hold it in place. Pulling the ends away from each other to "slim" the tube also seems to make it more rigid. If they end close enough to the ESC (I've got 15mm from the end of the sleeve to the ESC) they can barely move. Mine have always stayed close to the arm, I never need to reposition them.

Your notes will surely help me once everything is in order. Thanks for sharing! Hope you enjoy that Kopis 3"!!

Ok a little update on what probably was really causing the oscillations, I just discovered that 2 screws broke that secured my esc's to the frame.. And since the FC is on top of the ESC's I assume the whole stack was vibrating. All those hours spend on filters and PID's... Pff

Oh and I just received the Kopis Mini I recently won from JB's Giveaway and it's a lipo killing rocket!!
Just finished installing BF4.2 RCx on both 5 and 3 inch quads and finished tuning according to the tuning notes.
 
Time to surf those airwaves! 

I Present you: The Flying Lipo