TB70 Vibrations

[davehour]

Hi,

I’m getting extreme vibrations from a new TB70 being bench tested.
The model is working as expected and assembled as per manufacturer instructions.
This model is belt driven.
The motor/main drive pulleys and belt, and the tail pulleys and belt, mechanisms, generate inherent vibrations.

Please advise.

[ZeXx86]

If using Sensor Motion Filter to Low Latency this could increase vibrations in the analysis.
You can repeat with Standard option (after save and reboot). This should lower the readings.

[davehour]

The Sensor Motion Filter is set to Standard.

[ZeXx86]

Ah, then it seems the vibrations are really present, mainly at the tail rotor. How the unit is mounted?

[senaka]

the vibrations could be at a resonance frequency, which as a result creates such spikes at certain head speeds. With the blades out check the vibrations on several head speeds. I was plagued with vibrations on a new model. Which made me weigh each and every thing that rotates and balance them. I would also try to isolate it like spool only the motor with the pulley/pinion followed by motor + head assembly and then motor + tail. Also the Spirit is mounted firm with the included tape, so no anti vibration mounts as given with some SAB Kraken's.

[davehour]

Pictures attached.

The Rx wrap isn’t compressed to the Spirit GT.

In a tail belt drive, one can feel the ratcheting of the mechanism when the main rotor is rotated.

[davehour]

the vibrations could be at a resonance frequency, which as a result creates such spikes at certain head speeds. With the blades out check the vibrations on several head speeds. I was plagued with vibrations on a new model. Which made me weigh each and every thing that rotates and balance them. I would also try to isolate it like spool only the motor with the pulley/pinion followed by motor + head assembly and then motor + tail. Also the Spirit is mounted firm with the included tape, so no anti vibration mounts as given with some SAB Kraken's.

That’s quite a great systematic approach.
Thanks for sharing it and for your time.

[Mona]

The velcro stuff around the receiver looks like it's touching the unit. This way it will transfer vibrations from the frame and the mounting tape can't do its job. Spirit unit should be free.

[davehour]

Both, the Spirit GT and the Rx, move freely without interfering with each other.
It looks like the Velcro is touching the Spirit GT but it isn’t. The top layer of the Velcro just wrap the top of the Rx and ends there.

Nevertheless, I’ll remove it and retest.

[davehour]

Just curious if this model can be flown with those vibrations.