Hi,

So I was about to take my DJI Phantom 3 Standard flying but noticed that the back right propellor wasn't spinning (though it was rotating), even though I had tightened it on, and all the other propellors were fine.
Here are the observations I've made:

• I've changed the propellor to opposite one, which is working, but the same error occurs, leading me to believe it's not a fault with that propellor.
• If I tighten the propellor, the whole rotor doesn't spin as fast as the other rotors.
• If I place the propellor on loosely while the rotor is stationary, or if I rest the propellor on an already spinning rotor (so that it tightens when I start the rotors spinning), the rotor AND the propellor will spin at the correct speed - however when I increase throttle for take off, the propellor will spin off the drone. So basically if the propellor is hand tightened, it won't spin quickly, if I place it on loosely so that it tightens itself, it will fly off when throttle is increased.
  

This leaves me at a bit of a loss as to what the fault is. Has anyone experienced this before?

Thanks very much,

You might like to try tp explain exactly what the problem is in a simpler way.
I read it twice and it just confused me.

Can you fly or is your Phantom unflyable?
What does this mean?    the back right propellor wasn't spinning (though it was rotating)

You are sure you have black dot prop on black dot motor and silver dot prop on silver dot motor?

Yes, they will only thread on smoothly, if applied to the correct color motor shaft.
Black on black, white on white...

RedHotPoker

It sounds to me like the motor's shaft has dropped deeper into the motor so that the bottom of the propellor's hub is rubbing on the top of the motor casing, causing drag or friction and thus slowing the prop AND motor when the prop has been tightened onto the shaft.  

Only explanation I can think of for the behaviour described.

Sounds like you might have to change the motor or send it in for repair somewhere.

Edit to add - I suggest the motor shaft because you said you swapped the props with the diagonally opposite motor and the same motor repeated the issue - if the problem had moved with the first prop to the second motor I would say the problem was in the individual propellor's hub.

labroides@yahoo Posted at 2016-6-12 01:26
You might like to try tp explain exactly what the problem is in a simpler way.
I read it twice and i ...

Hey, sorry
When I was saying that the the propeller spun but didn't rotate, I meant that it sort of spun at like one rotation per second, as proposed to how much you expect it to spin when it's idling (as the others were).

It's unflyable - either its not spinning fast enough to let it fly (if I tightened the propeller) or it the propeller flies off.

Pretty sure I have black-on-black but will double check later today just in case.

Old Geezer Posted at 2016-6-12 02:38
It sounds to me like the motor's shaft has dropped deeper into the motor so that the bottom of the p ...

I think I understand what you're saying. I'll have a look to see if there's anything visually to support that but it sounds like the most likely reason behind what seems to be slightly conflicting symptoms. Either way, seems I'm going to have to take it to get repaired :/

imaginewizard Posted at 2016-6-12 03:14
I think I understand what you're saying. I'll have a look to see if there's anything visually to s ...

Have you got a small steel/aluminium ruler - the type where the mm marks go to the end of the ruler?

You could use that to compare the shaft/spindle height above the motor casing.  Also check the clearance between bottom of prop hub and motor casing.

Do you have spare propellers?  You can buy a new  and replace the old ones to see if it works.  If it doesn't, then clearly issue comes with your rotors and you have to return them to DJI for repair.  

Old Geezer Posted at 2016-6-12 12:18
Have you got a small steel/aluminium ruler - the type where the mm marks go to the end of the rule ...

The threaded shaft cannot sink as it is the same piece of metal as the entire motor casing.

imaginewizard Posted at 2016-6-12 12:11
Hey, sorry
When I was saying that the the propeller spun but didn't rotate, I meant that it sort o ...

It's still confusing but there are only two areas to l;ook into.
The problem is either:
1.  The prop isn't attaching to the threaded shaft properly (sounds like this isn't the problem)
2.  You have a problem with a motor

Forget the props.  Start up the phantom with no props and see if all motors are spinning as they should.
Rev it up a bit and carefully hold the suspect motor casing to see if it is spinning strongly.
If it is, it doesn't sound like a motor problem.

Check the props.  Do the black ones screw down properly so they are firmly seated?
Is there any slop ... can you keep turning the prop or does it lock down?
If the props are seating properly and your motors are doing what they should, go flying.

Sounds like the threads are stripped where the prop hub meets the mount. I wouldn't trust it. You may want to send it in to a Service Center or a Dealer and let them check it for you before you lose your Phantom to a crash.

rodger Posted at 2016-6-12 20:49
Sounds like the threads are stripped where the prop hub meets the mount. I wouldn't trust it. You ma ...

The threads are nylon engaging the metal of the motor shaft.
It's a simple matter to throw out a prop that doesn't lock and it's easy to check the motor spindle threads.
There should be no need to send anything to DJI if it's a thread issue.

labroides@yahoo Posted at 2016-6-12 06:58
The threads are nylon engaging the metal of the motor shaft.
It's a simple matter to throw out a p ...

If you read it instead of being sarcastic all the time to everyone that posts all the time with your negative comments you may after time see that he tried the prop on another motor and it is fine eliminating the thought that it is the prop. So, it may be the motor shaft and therefore the motor may have to be replaced and it would be best done by a DJI qualified repair center.
Please do me a favor and not address any replies to me as I will not reply to them as I have not done in the past and will not do in the future. This forum is to try and help others as they are looking for an answer and not an insult to their intelligence. I have been holding back for a long time and today is enough is enough.

rodger Posted at 2016-6-12 21:12
If you read it instead of being sarcastic all the time to everyone that posts all the time with yo ...

So .. if it's the motor thread, that should be easily checked visually and by feeling it with the fingertips.
It  only has to engage with nylon so it's extremely unlikely that it should be deformed.
As for the  rest  of your post .......sorry you are so  oversensitive.
If you reread my posts you should see that  there's no sarcasn there ... I'm just trying to help users.
You can ignore my posts if you choose, but I'm not going to  change anything for you.

Hallo all, my first post here, I only have a month a Standard. For your case imaginewizard, because you say.....if I place it on loosely so that it tightens itself, it will fly off when throttle is increased....,  I think you have a propeller with wrong color or somehow the rotor spin the wrong way. Check please if the rotor spin the way of the legend on the upper case and the propeller is the same with the opposite, not only the color.

panofi Posted at 2016-6-12 08:18
Hallo all, my first post here, I only have a month a Standard. For your case imaginewizard, because  ...

Good possibility and welcome aboard.

rodger Posted at 2016-6-12 07:12
If you read it instead of being sarcastic all the time to everyone that posts all the time with yo ...

Not defending the chap you are trying to diss, but you need to read the OP yourself before you complain that someone else should read it before commenting:

"I've changed the propellor to opposite one, which is working, but the same error occurs, "

So, as you can readily read, the problem persists on a different motor.

FAS1 Posted at 2016-6-12 15:12
Not defending the chap you are trying to diss, but you need to read the OP yourself before you com ...

Hey sorry! I think this brief conflict is my fault - just to clarify the fault only occurs on the back right rotor - regardless of the propeller. The fault therefore doesn't seem to be with the propeller. When I say I switched the propellers around diagonally but the error still persists, I meant on the same rotor. The other rotor spins fine.

labroides@yahoo Posted at 2016-6-12 04:14
It's still confusing but there are only two areas to l;ook into.
The problem is either:
1.  The pr ...

Hi - so I tried this last night - ALL motors spin fine when no props are attached - and also spin fine if I attach the prop on loosely to the back right rotor (only then it flies off when I rev it to take off). It only spins slowly if I tighten the prop.
The prop does tighten until it gets stiff (I assume that's what you mean by lock down), so I can't keep turning it. However when that happens, the rotor doesn't spin at idle speed, it just rotates slowly.

panofi Posted at 2016-6-12 13:18
Hallo all, my first post here, I only have a month a Standard. For your case imaginewizard, because  ...

I'll double check to make sure it spins the right way, thanks!

imaginewizard Posted at 2016-6-12 16:00
I'll double check to make sure it spins the right way, thanks!

Best thing for clarity is to video the problem & post it on here for all to see.  Sounds very odd to me, since I can't imagine any reason that tightening the prop would affect the rotation speed of the motor.

nigelw Posted at 2016-6-12 17:00
Best thing for clarity is to video the problem & post it on here for all to see.  Sounds very odd  ...

I shall do that.
I'll need to find something to tie the drone down so it doesn't crash when I increase the throttle. I've been holding it down with my hands before but I decided that was a bad idea after I managed to slice open my arm yesterday when it tilted towards me

imaginewizard Posted at 2016-6-12 16:58
Hi - so I tried this last night - ALL motors spin fine when no props are attached - and also spin  ...

Did you really check, double-check; triple-check that you put the black and silver propellers on the right motors ? The difference in color is rather subtle.

imaginewizard Posted at 2016-6-12 16:17
I shall do that.
I'll need to find something to tie the drone down so it doesn't crash when I inc ...

Also bee sure its rotating the right way CW.  Have you flown it before or is it the first time you try to take off? The only time I have seen this was because of bad IMU calibration but that will not make the prop go of.

imaginewizard Posted at 2016-6-12 09:17
I shall do that.
I'll need to find something to tie the drone down so it doesn't crash when I inc ...

Remove the props from the phantom for the video and show the issues with the motor. Take the video in slow motion .. as this will show the direction it is spinning.   To me it has no benefit putting the wrong prop on the motor with the problem, this only confuses everyone.

1) run without props and check the motor operation
2) try a new prop on the motor with the issue
3) is the motor getting hot

If the problem persists then you might get someone with experience in your area to help you, or the hobby shop. If this continues send it to DJI to repair

Rich

Well, If the motors spinning, its possible that the problem is in one of the Speed Controller (ESC).

RichJ53 Posted at 2016-6-12 19:30
Remove the props from the phantom for the video and show the issues with the motor. Take the video ...

I can't film in slow motion, I don't have a high speed camera, but feeling the motors I can tell they are spinning the right way.

So I did an IMU callibration, and nothing has changed except now the propeller doesn't seem to fly off when I throttle up. When I tried flying it, however, it didn't take off as much as flip on to its back so ...

The rotor still rotates slowly if I hand-tighten. However if I let it self-tighten it does the above (and then will, at apparent randomness, either need loosening again to let it self-tighten for it to spin fast, or just spin fast anyway).

It seems something is up, and I'm going to be near a repair shop tomorrow so I might just visit them.

I have filmed a video, so will edit and upload that.

imaginewizard Posted at 2016-6-13 03:45
I can't film in slow motion, I don't have a high speed camera, but feeling the motors I can tell t ...

Interestingly - one week ago - I lost my P3P because of an in flight prop spin-off from the right rear motor. My "classic" P3P got the new motors and ESCs after the repair of a shell crack.
I flew more than 45 hours with my original old motor configuartion. After just 2 hours my overhauled "new motors"-P3P fell out of the sky.
As I said: like for you my right rear motor is affected. My prop spinned off most likely due to the "Motor obstructed" switching/message that occured in mid air...
I've sent my crashed P3P to the repair center waiting to hear about the "official" reasons for the P3P crashing with just 3 props on...

OH also yeah just to confirm I have flown this drone quite a few times before the error developed.

J.N Posted at 2016-6-12 19:40
Well, If the motors spinning, its possible that the problem is in one of the Speed Controller (ESC).

I agree, it sounds like the motor spins up ok without a load then hasn't got the power to overcome the inertia with the prop fully attached, or maybe one of the motor wires has become disconnected & it's only running on 2 out of 3 phases?

nigelw Posted at 2016-6-13 00:37
I agree, it sounds like the motor spins up ok without a load then hasn't got the power to overcome ...

Is the ESC a software thing? (As in can I check this in the app or whatnot?)

Here's the video I made. I made this after recallibrating the IMU - which for some reason prevented the propellor from flying off in the situations where it previously did (but instead now it just causes the aircraft to flip on its back).

imaginewizard Posted at 2016-6-13 10:22
Here's the video I made. I made this after recallibrating the IMU - which for some reason prevented  ...

OK ... you have a problem in the propulsion system.
It's nothing to do with props and threads or loose props.
It needs to go in for repair.

ps ... be careful with that thing you used to weigh the Phantom down

Yup. It's screwed...Send it in. Should be a warranty repair?

imaginewizard Posted at 2016-6-13 08:22
Here's the video I made. I made this after recallibrating the IMU - which for some reason prevented  ...

Motor is single phasing. It will run MOST of the time but will have very little power. It also can run in either direction at start up if is is single phasing. I suspect the wind velocity for the other props is causing this motor to bump start in the reverse direction. This will cause a prop spin off.

Regardless the bird will need to go in for repairs.

rodger Posted at 2016-6-12 19:12
If you read it instead of being sarcastic all the time to everyone that posts all the time with yo ...

"If you read it instead of being sarcastic all the time to everyone that posts all the time with your negative comments ... "

???

I went back to read his post three times and saw no sarcasm or negativity.

Hmm... perhaps the drone is frightened of the guns? ))

Seriously, a motor or esc problem.. I would go for motor, as ESC would probably get reported... did you have a crash or some other possible impact to that one motor?

Good luck opening a case and getting this looked at!

Oh, since you powered on the motors, you could try to find the log for that specific "flight" on the drone, and see if the log will give you anything useful, but I'd still ping DJI first, being in the UK, I assume it should be relatively painless, they got to have a DJI service center there.

On a side note, I googled" sarcasm detector" totally hoping to find one on line.. and I did not!!! Does that not suck?! I so wanted to run this, and many other threads through it!

FAS1 Posted at 2016-6-12 10:12
Not defending the chap you are trying to diss, but you need to read the OP yourself before you com ...

I am not dissing him. I guess we are reading his statement differently. He said he changed the prop to the opposite one which is working and has the same error. That would lead me to think that the issue is with the motor and not the prop.