Hi Guys,
I have flown about 75 times as of this writing. At the startup of the proposed last flight, myself and my spotter heard a sound that that we never heard before. The best way to describe it would be a momentary "ping-ping" and then no other sound other than the typical motor sound. Almost as if you were to lightly tap a wine glass with a fork twice gently. It was enough to cause me to ground the i1 for the day.
Having not flown since, I wanted to take a look at things to see what the issue was. I spun each of the motors by hand forcefully to get several rotations out of them (no props attached). Three sounded/acted normally. The fourth, exhibited a "ping" when I spun it. I tried again and again and no further pings were heard.
My thought was that I was going to remove the top two screws on top of the motor and take a look (I have the quick release style prop attachments). I put my allen driver on the screws and they were BOTH markedly loose!
I then went to the other three motors and they were loose too, although not as much. I extracted the screws and found something VERY INTERESTING. There seemed to be an absence of threadlock. Having dismantled parts of the body previously for various reasons, I found blue threadlock on the body screws, but none on the motor screws. That seems extraordinarily odd to me. I would think that threadlock should be more important on the motor screws than anywhere else! Well, upon further inspection, after extracting the screws, I could see blue threadlock in the screw hole, BUT NONE ON THE SCREWS! Apparently, the blue threadlock installed by the factory, did not adhere to the screws. This is quite alarming considering the importance of these specific screws.
So, I have added blue threadlike to these 8 screws and reinstalled them.
I wish to advise all i1 owners to check these screws before your next flight to make sure they are tight and additionally I recommend checking for threadlock and adding it if it is absent.
Lastly, I would like to hear whether any other members' motor screws were discovered to be loose as well.
Safe flights everyone,
Ken
I have flown about 75 times as of this writing. At the startup of the proposed last flight, myself and my spotter heard a sound that that we never heard before. The best way to describe it would be a momentary "ping-ping" and then no other sound other than the typical motor sound. Almost as if you were to lightly tap a wine glass with a fork twice gently. It was enough to cause me to ground the i1 for the day.
Having not flown since, I wanted to take a look at things to see what the issue was. I spun each of the motors by hand forcefully to get several rotations out of them (no props attached). Three sounded/acted normally. The fourth, exhibited a "ping" when I spun it. I tried again and again and no further pings were heard.
My thought was that I was going to remove the top two screws on top of the motor and take a look (I have the quick release style prop attachments). I put my allen driver on the screws and they were BOTH markedly loose!
I then went to the other three motors and they were loose too, although not as much. I extracted the screws and found something VERY INTERESTING. There seemed to be an absence of threadlock. Having dismantled parts of the body previously for various reasons, I found blue threadlock on the body screws, but none on the motor screws. That seems extraordinarily odd to me. I would think that threadlock should be more important on the motor screws than anywhere else! Well, upon further inspection, after extracting the screws, I could see blue threadlock in the screw hole, BUT NONE ON THE SCREWS! Apparently, the blue threadlock installed by the factory, did not adhere to the screws. This is quite alarming considering the importance of these specific screws.
So, I have added blue threadlike to these 8 screws and reinstalled them.
I wish to advise all i1 owners to check these screws before your next flight to make sure they are tight and additionally I recommend checking for threadlock and adding it if it is absent.
Lastly, I would like to hear whether any other members' motor screws were discovered to be loose as well.
Safe flights everyone,
Ken