I crashed the quad a couple of times, weird noises, instability and wiggling in mid air

Mehigh

Mehigh

Member
Hello,

I have recently finished my build, I still have no FPV cam on it though, I'm waiting for the package to arrive. I already flew the quad a couple of times and crashed it unfortunately, yet it had no visible damage, everything was working ok ... Today I kinda crashed it VERY hard and after the crash the quad started to tilt to right automatically, and wobble as soon as it got in mid air. I accelerated the motors one by one to see if it had any damage, I hear nothing. But as soon as I push it into mid air, it starts wobbling and tilting to right, also making a very ugly noise, like it would have tension loss or something. I really don't know what could be wrong, I would say the motors or the batteries. Although, I pushed each motor at 100% to see if there's a vibration or noise, there's none, but there is after it gets in mid air.

Video of it:

More detailed video of the noise:

**The opposite motor is doing the same noise! http://imgur.com/af57xQI

PS!!! The motor isn't making that noise when accelerated independently!!!
 
I've had that kinda noise before but it was a loose solder joint from motor to esc.
But you should try recalibration of the esc after you Reflow all motor solder points.
But looks like to Mr you killed them. If you got a spare motor or esc, put it on.
Eliminate the baddy. So redo the joints then calibrate, go fly.. Then swap em out if not work.
 
mozquito1 said:
I've had that kinda noise before but it was a loose solder joint from motor to esc.
But you should try recalibration of the esc after you Reflow all motor solder points.
But looks like to Mr you killed them. If you got a spare motor or esc, put it on.
Eliminate the baddy. So redo the joints then calibrate, go fly.. Then swap em out if not work.
Click to expand...

I haven't thought at this. Indeed there might be a very loose soldering on the Flight Controller, it was my first time when I did soldering when I created this quad and I didn't put too much soldering iron. I'll go and redo the soldering entierly.
 
If new motors it's not the bearings. If you got a spare motor put it on. if still same try a new esc. If back motors are OK, 1&3 then just swap em out till you find what is dodgy. Just a process of elimination. When you buy parts always buy a spare.
 
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Are you using the pins or have you soldered onto the holes. On the fcb.
Have you got a servo tester if not it's worth getting one just to test each motor & esc when you get them. Then you know they OK b4 u put em on. But to me it looks like you killed a motor. Just take one off the back if it works properly there it is. Usually when esc's go they go kuput full stop. In my experience anyway.
 
mozquito1 said:
Are you using the pins or have you soldered onto the holes. On the fcb.
Have you got a servo tester if not it's worth getting one just to test each motor & esc when you get them. Then you know they OK b4 u put em on. But to me it looks like you killed a motor. Just take one off the back if it works properly there it is. Usually when esc's go they go kuput full stop. In my experience anyway.
Click to expand...

I use the pins on the FCB, I find that more practical when cleaning the quad. I don't have a servo tester unfortunately nor I knew of its existence. I'll try to swap the engines but personally the sound is very unpleasable and it acts like there would be metals touching eachother when this happens.
 
You may have bent the bell. So it rubbing on the stators. If so it's dead. You could buy a new bell. A servo tester is only 3-4 bucks. But a good way to test stuff instead of getting the quad together then realising it's bust. A continuity meter is handy aswell before you plug any battery in.
 
mozquito1 said:
You may have bent the bell. So it rubbing on the stators. If so it's dead. You could buy a new bell. A servo tester is only 3-4 bucks. But a good way to test stuff instead of getting the quad together then realising it's bust. A continuity meter is handy aswell before you plug any battery in.
Click to expand...

It's weird because it happens only when hold at a given precise angle (as you can see in the video). Otherwise it doesn't do the noise.
 
U can try oil but most motor bearings these days are enclosed. It does no good just collect dirt. Did you try swapping one of the good motors to eliminate the esc as a problem. It maybe a pain in the aasss but if it is still wobbly or whatever from the crash try a gyro reset or failing that a board reset. You will lose settings but you can load them up if you have them saved. My quad kept flipping out but all wiring was correct. It was only wen RENOV8R said try the reset that it sorted the problem.
 
mozquito1 said:
U can try oil but most motor bearings these days are enclosed. It does no good just collect dirt.
Click to expand...
That is simply incorrect. The basic design of high speed, miniature bearings is well established and decades old. Actually The first modern patent on ball bearings was by Philip Vaughan, a Brit who created the first design for a ball bearing in in 1794. FWIW a few drops too many of oil can often actually clear out debri as the bearing spins up. What has come a long way is lubricant technology.
Proper bearing lubrication is vitally important to the optimal operation and life of miniature bearings... Normal wear and damage due to sliding contact, corrosion, contamination, and heat will accelerate in the absence of proper lubrication reducing bearing life significantly.
Click to expand...
http://www.nationalprecision.com/miniature-bearings/lubricants.php
 
@Jackson

Short update on this. I tried to flash the firmware of the ESCs today (first time I do it) and the second ESC (#2)(the one that is doing the troubles) is not in SYNC with the master. I don't really know what that means. But the motor 2 on the ESC 2 is the one making the troubles, you have more infos here:

Q7SBYxx.png
 
Update 2: I synced all the ESCs, the sound is still there, I really think these motors are broken, the sound is exactly like there are two dry metal parts touching each other.
 
Jackson said:
That is simply incorrect.

Everything I have killed a motor I see what I can salvage off it. I got some spares & bought spares for different motors. All the bearings in motors I have had are enclosed, crimped together. Simply spraying oil on them has no effect. Suppose you could try immersing them, some might seep in. I bought the best fine grade sewing machine oil icould get without ordering from China. Had no effect.
Click to expand...
 
So your problem was the battery you think. Sorry I do not. A battery would just give less voltage with a broken cell. Not give spikes like in that video.
 
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