Clipping on Z axis after change to t-motor cf propps

Hi,

I just did a test with my t-motor foldable polymer propps and my new t-motor carbon fiber propps, not the NS ultralight or the glossy, just the mate CF propp.

The copter runs 22 inch and weighs in at around 9kg

I thaught the carbon propps would perform better than the polymer once, at least vibration vise. But now I got clipping on my third IMU. I’m using a cube orange so the third is not dampened but with the polymer propps, the third did not clip.

Log with straight CF propps.

Log with foldable polymer propps

Any input is appreciated!

@xfacta I looked over a couple posts about Z axis vibration, in one you mentioned that propps too close to the arms could cause issues. My propps ended up very close to the arm.

I also found that Z axis vibrations could be caused by not so well balanced propps, but the t-motor fixed propps that shouldn’t be an issue, right?

You need to balance all props. Well, at least the ones that can be balanced.

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I thaught the T-motor propps would be balanced by them,


These are the once I’ve got

I would never rely on that. It’s like a 15 minute process.

Is it possible to balance these propps? Or are they too thin to remove anything from?

Sure it is. I use fine sand paper. Balanced many a CF prop that way.

What tool should I use to balance it? I’ve never balanced any propps myself before

You have to buy a balancer. They go from cheap, which is what I use, to Dubro, the maker of very nice ones.

Cheap:
Balancer

with that one I wouldn’t be able to spin the propps all the way around, but maybe I just need to balance it when it’s laying horizontally

Well, yea…

I see there are knock-offs of the Dubro balancer for much less. From the usual Chinese companies like Mrgoodflyhappy or some such.

I might have to get one of those than. I had the propps mounted directly on the motor so it ended up directly over the arm, maybe that would be an issue?

Do you know of any other things that could cause Z-axis vibrations?

@xfacta
@dkemxr

I’ve conducted some more test flights regarding my issue with the Z vibrations. I swapped back to the polymer props and the vibrations went down. At least the non dampened IMU shows that. The dampened IMUs shows slightly higher vibrations but not peaking abow 30.

With the polymer props the amplitude on the fft graphs is also much lower on many of them. So I believe that the dampened IMUs showing higher vibrations is just my drone interacting badly with the internal dampening of my cube orange.

But for my choice of props, it would be better to use the polymer with lower actual vibrations even if the dampened IMUs show a but higher, right? That would put less strain on mechanical components and make it easier to filter vibrations for the camera right?

Other than that, I would really appreciate if you guys could take a look at my two tests and see if there is anything else like RATE noise or anything else I’ve might missed or don’t understand that would make one prop choice better that the other.

First flight with carbon propps:

Second flight with my original polymer propps:

Thanks!