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Maybe instead of carbon fiber blades a more useful release would be a carbon fiber upgrade body kit.
Catastrophic design flaw of Phantom 3
- Thread starter Chris Vedeler
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I got my Strong Arms yesterday and had been on the fence about installing them until I saw this thread. Taking the afternoon off today so will get right on it. Doesn't seem like a problem exclusive to P3s either, one of my P1.1.1s is developing a stress crack too.
I have looked everywhere for how to adjust the active braking. It's probably right in front of me. If you could tell me where that is I would be very grateful. I'm using Android if that makes a difference. Thanks
Do you think quick release prop guards would have prevented the failure? They only cover the 4 motor screws, but it seems like the guard mounts beef up that area significantly.
Meta4
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In the app, go to MC settings, click on Gain & Expo Tuning and then go down the next page that comes up.
Under gain and expo. You'll just need to scroll down. Screenshot attached. I have mine set at 70...does not show in this screenshot because the Phantom isn't connected.
Attachments
I've had Bestem Aerials prop guards from the start and so far no issues as the guards are clip on but the fitting to arms is solid as. So sorry to hear abt your bird
But, did you zip tie bro? I noticed cracks in my P3. Zip tied all the propellers no more cracks. Been flying around for about a month now. It never got worse or anything.
I doubt zip ties would have helped. Take a look at the pictures. The motor came right off the mounting plate.
Zip ties could have definitely helped.
If my P3 started developing cracks and I can tell from the softened plastic that it was only going to get worse. They are small hairline cracks. Had I not put the zip ties I can tell that there would be chunks of plastic missing. Now, going back to OP. Just because his situation is a lot worse lets take it back to the basics. If theres is small plastic cracks that lead to chunks of plastic missing. Whether its due from over heating, high torque rates, breaking and accelerating too fast, or weak design of plastic. It doesn't matter. Bottom line is it cracks and only gets worse. Now if one of those cracks shows up around an important screw. Lets say, a screw holding the frame together or a screw holding the motor together. Guess what happens? the motors become loose causing exactly what you see here. Once that motor becomes loose the high speed of those motors spinning will scratch, burn, melt, break and crack nearly any plastic it touches. Plus the huge chunk of plastic missing where the motor screws go. Brings me back to my point. Zip ties coud have prevented this. Do I blame the OP? HELLLL NO we p3 users shouldn't even have to put zip ties around our props thats foolish. Sure beats sending it in for 3 months. DJI should be coughing money up to users experiencing this. They designed a poor quad copter.
Oso
Premium Pilot
Interesting thought. I did see a crack in the same arm of Chris' P3 in his original post in another thread. I highlighted it here, but noted that we really cant tell if there were also cracks around the motor screws. Perhaps the arm screw crack led to instability as you suggested. Still, as you also said this is all on DJI. Its such a shame given the truly amazing level of the technology in the P3 that something as simple as the shell can bring it down.
You'd need to zip tie the motor to the wing to make it help. Zip tying the two shell halves together would have done nothing in this case.
Very well pointed out. But, it goes back to what I was saying before. The motor screws probably had no damage before this disaster. But, the screw holding the shell together probably had slight cracks causing the motor to eventually wiggle? loosen? Even the slightest bit of loosening I can imagine would cause such chaos to the motor, frame, shell and screws. Just a thought. Once again I don't blame OP. Its just another reason why to throw on these zip ties people.
Too me it seems it could be related to vibration. When I hand catch my P3 I noticed it had more vibration then my other quads. It may be related to out of balance props or possibly the higher thrust props are exerting extra force into the frame. Also I think as others have mentioned the active braking may be exerting additional stress into the airframe...
I really think the plastic on the P3 is too brittle. Even though the P2 had signs of cracking, the shell felt more flexible.
DJI probably lightened it to get more flight times or stiffen the plastic to make it more rigid for better reaction times (reaction times isn't needed because its not a stunt quad).
At first, I thought it would be from climate change or over-torqueing. I guess I'm wrong. I have tiny microfractures on the rear motor ends. I had less than 40 flights. Looks like a combination of crap plastic and vibrations causing the cracks. Going to open her up and use hot glue gun on the stressed areas and prevent it from worsening. I've done this with my P2 and worked a charm.
It's going to void my non-existent DJI warranty and being in Australia doesn't help... We have zilch DJI support out here.
DJI probably lightened it to get more flight times or stiffen the plastic to make it more rigid for better reaction times (reaction times isn't needed because its not a stunt quad).
At first, I thought it would be from climate change or over-torqueing. I guess I'm wrong. I have tiny microfractures on the rear motor ends. I had less than 40 flights. Looks like a combination of crap plastic and vibrations causing the cracks. Going to open her up and use hot glue gun on the stressed areas and prevent it from worsening. I've done this with my P2 and worked a charm.
It's going to void my non-existent DJI warranty and being in Australia doesn't help... We have zilch DJI support out here.
Chris - Can you do a favor, please?
I have long suspected that the Phantom shells from the beginning have been injection molded polystyrene or styrene hybrid. Would you mind please applying a small amount of acetone or acetone-based fingernail polish remover to one of the damaged pieces to see if it softens within a minute or so? PS is not really a good chice for long term vibration absorbtion without careful design to minimize any kind of stress concentrations (thicker skins and bosses and gussets and smoother transitions and radii).
With your results - I am very sorry this happened to your P3 - I realize the only possible robust prevention is to use a backing plate (the reinforcements made for this or removable prop guard brackets). Obviously, we cannot change the material and it will be a while before DJI redesigns the gussets and bosses and knit lines etc to anticipate the failures due to long term vibration. With all their good computing and engineering skills, I am surprised they didn't do FEA (finite element analysis) over a virtual long life. Yup, I used to do that very thing for a toy company.
I have long suspected that the Phantom shells from the beginning have been injection molded polystyrene or styrene hybrid. Would you mind please applying a small amount of acetone or acetone-based fingernail polish remover to one of the damaged pieces to see if it softens within a minute or so? PS is not really a good chice for long term vibration absorbtion without careful design to minimize any kind of stress concentrations (thicker skins and bosses and gussets and smoother transitions and radii).
With your results - I am very sorry this happened to your P3 - I realize the only possible robust prevention is to use a backing plate (the reinforcements made for this or removable prop guard brackets). Obviously, we cannot change the material and it will be a while before DJI redesigns the gussets and bosses and knit lines etc to anticipate the failures due to long term vibration. With all their good computing and engineering skills, I am surprised they didn't do FEA (finite element analysis) over a virtual long life. Yup, I used to do that very thing for a toy company.
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I didn't have straight acetone but my used my wife's nail polish remover which is mostly acetone. It had not effect on the plastic.
Actually, that is good news - Thanks! The only other times I have seen this occur for an injection molded part, either (1) the resin beads were kept in too much of a humid environment, or (2) injection or cooling cycles were too fast. Oversimplification of course.
I believe DJI can improve the mold by widening some radiuses and/or using a slightly tougher (as in energy-absorbing) material.
I hope so. The thing is DJI will never admit fault due to legal blah blah. They'll simply release a revise V2 model and sneakily upgrade//fix the known issues.
They will never compensate or do a recall unless someone dies. Zero social responsibility.
On a positive note... DJI announces free carbon fibre bodies for everyone!!!! Sarcasm dance - yay!!!
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