Preventing props from coming off during flight

[asr]

I recently bought a gamepad and am now able to use the Crazyflie's altitude-keeping functionality which is great. However, almost every flight ends up with a prop coming off during flight, which is hugely frustrating, especially since I'm not doing any aggressive maneuvers, and am simply flying around the room sedately. I've looked at the blog post regarding poor prop quality (https://www.bitcraze.io/2020/03/propell ... ity-issue/), which has affected one of my props so far, but looking at the props that come off during flight, I can't see anything wrong with them.

When putting the errant prop back on the Crazyflie, I make sure to press down fairly hard, and also press down on the other 3 props before flights to ensure that they're also attached to their respective motor shafts well. However, this doesn't seem to help, and I'm at a bit of a loss at what to do next. I don't really want to glue them in place, in case I do actually get a broken prop and can't remove it from its motor shaft. As such, I wanted to know how common this issue is, and what others have done to prevent this from happening. Is there a way to attached the props more securely, while still being able to remove them if they actually need to be replaced? Any help would be appreciated.

[kimberly]

Hi,

When did you order you crazyflie? Since the latest ones should not be affected by this. Also the micro tears that happens to the holes of the props are usually not see-able without a magnifying glass.

If the props are easy to remove from the motor shaft with very little effort, then they are a bit too wide. I would say that hot glue (like with an hot glue gun) would be fine, as long you are careful that no glue will prevent the motors from turning or change something to the aerodynamics of the propeller. Hot glue is very easy to remove from my experience, but definitely do not use super glue or anything similar.

[Flanker27SK]

Yes, I had the same issue with my Crazyflie when I got it a couple months ago, and I can confirm that the hot glue method works perfectly.

[mittens]

Hi there,
I tried hot glue as well as super glue method. But still the propellers are coming off within 10-15 seconds of flights.

Do you have any other suggestion? Running out of extra propellers that were provided. Is there option to switch to a different motor / propellers?

[kristoffer]

We have unfortunately had some issues with production quality of our propellers, see https://www.bitcraze.io/2020/03/propell ... ity-issue/
If you think your problem is related to this, please send us an email at contact@bitcraze.io