Yeah I understand coil and rebound, just not sure I can do that here.
I do have heavier springs for the arms I can use and wondering if there is any form of padding that can be added to them to reduce noise.
possibly something to design.
Some of the film guys use cable as a spring wonder if they achieve some damping.
I currently have a cable dampener on the FC and that works well but not enough to make me happy. The biggest issue is Z axis and the Cable dampener just isn’t doing it. Going to try the o-Rings next and see how that works out. @mboland seems to have good luck with it so I will give that a go this weekend.
But after that I am not sure what to do.
Soft mounts on the motors is not affective I suspect thats because the vibration isn’t the spinning motor but rather some other form of vibration being introduced.
I don’t have much experience with caseless FCs, but I mounted a Kakute F7 on a small quad, once and I used ear plugs hotglued to the frame and squeezed through the FCs holes.
Hey Cornel I have tried that method and while it does work, it doesn’t knock the vibes down into the space I want them to be. But thank you for the suggestion it’s greatly appreciated.
I have made one observation.
First the machine has a CCW YAW bias that I am going to try tuning out this weekend. I can see Motors 1 and 2 work harder then 3 and 4. So this tell me a CCW YAW bias. But the other thing thats interesting is that when Motors 1 and 2 are working harder the vibrations are higher.
Here is high vibes, motors 3 and 4 are not working hard and 1 and 2 are. High vibes.
Here is Low vibes, motors 3 and 4 are working harder then before but not as hard as 1 and 2. Motors 1 and 2 are not working as hard as they are during high vibrations and the vibes are low.
Also it almost looks like giving the machine a Clockwise Yaw command increases vibrations.
I wonder if just tuning out the YAW bias will reduce the vibrations overall. If I get it right all motors would run around the same. Balancing the demand, perhaps this will also affect vibrations. We shall see
An old crash test dummy quad sat in the shed for 4 years and I noticed a broken one on the mount.
I think a sharp edge on the board has nicked silicone.
In operation I have never had one break.
Which brand of prop did you switch to ? Except for a small training rig I have using Phantom4 motors and props on 4S, the 6S and 12S crafts are mostly TMotor props, and vibes are not an issue.
There’s also a cheap clone prop that I like alot. It’s off the first DJI S800 hexa prop. It’s listed by the chinese as 15x5.5 while actually being a 15x4.3. Does a decent job with smaller sub-100g motors like antigravity 4006 and heng-li 4008. Clones need some static balancing, but afterwards the vibes are low and smooth.
So results from todays test flights.
I worked to tune out the Yaw Bias.
This is the ESC RPM before the tune
This is after
In each test I took off in Loiter and hovered at about 6 feet for 1 minute and then landed. Pulled the logs and then tweaked the motors.
You can see that the motors are very close now.
This is the vibrations
This is before the o-Ring mount.
This is after the change to the O-Ring mount.
The X and Z axis vibes are AWESOME but Y axis is worse. Very odd.
Open to any input.
Just wanted to point out that in Mission Planner you can view a graph of the motor outputs in real-time during fight. Should help quicken this process in the future if the problem ever arises on another aircraft.
Hey thanks. I didn’t know that. I don’t’ think it would have helped necessarily as I needed to tweak the motors position on the ground. But that’s helpful information.
cheers
Yeah - just check the “Tuning” box on the bar below the map in the main data screen. Pulls up a graph - double click on graph - several values you can plot in live. Just removes the need to download logs sometimes.
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With a sprung mount you can now check the tension in the different directions.
My bet is that the Y direction tension is different, so just make it the same as the X direction.
Test again 
Also double check the prop balance on the arms in the Y direction, security of the arm and motor, the usual checks, but you have a direction pointing you to that side of the copter.
Propwash impacting cables, perhaps ?
Looking nice… I say your good to go. 
you can manually turn down the Y pid a few clicks.
@manavgandhi17 That’s interesting I will keep it in mind. It would let me see the Z axis live. That’s cool.
@mboland Not sure how I can check the tension. The mount is square and the flight controller is as well so I can’t see how I would make that sort of change.
I have considered perhaps changing the shape of the mount itself to a rectangle to see what the results are there. Also wondering if I should double up on the O-rings.
The other thought I had was to put the dampener grommets back into their respective holes and pass the o-rings through them and not directly against the end of the hole.
But I am not sure if that will help. I can say that the vibes are REALLY improved on 2 AXIS…like WOW improved. But Y axis is over the top. Luckily no clipping still.
@ThePara Cornel, no prop wash on cables everything is under cover.
I have a suspicion as to what might be causing the vibrations. But I am really puzzled by it being only on the Y axis.
Just to annoy everyone, there’s a Cube Orange on a mini carrier board stuck directly to the frame deck, and a Here3 stuck directly to the top of the Cube
Vibes are not an issue at all and tuning has come up great.
1 test flight for basic control tests and gathering pre-filter FFT data.
2nd test flight with Harmonic Notch filter all set up and run Autotune.
Job done! This unit has been doing work since then.
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hahahaha consider me annoyed. hahahahahaha
Thats a really cool little drone. Very clever in the way it’s been put together.
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Hi Shaun.ive had a Hexsoon from when they came out ive just rebuilt my one and fitted retractable undercarriage,I love this frame just come back to flying after being away because of ill health,can I ask what batts you are using please,just been out and only getting around 11 mins for some reason I thought I used to get 20mins on my 6250 x 4s li-on https://www.dropbox.com/s/7b52hdk3sp46u46/20210613_231619.jpg?dl=0
Doubling up on the O rings is a good idea as you can see I usually do that.
The down side of the pixracer mount is you dont have the mass of the lead sheet to adjust your vibration dampening.