Do Motor Mount Reinforcments Work?

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With some of the reports on stress cracks, I was thinking about getting some motor mount reinforcements as a preventive measure. But do they really prevent cracking? If the cracks are due to motor vibration, how does putting a plastic plate underneath it prevent that? Looking for feedback

Thanks guys!
 
With some of the reports on stress cracks, I was thinking about getting some motor mount reinforcements as a preventive measure. But do they really prevent cracking? If the cracks are due to motor vibration, how does putting a plastic plate underneath it prevent that?
If cracking was due to motor vibration or lots of other suggested causes, most P3s would have developed cracking.
But as only a very small number ever got the cracking, the theory that it was due to bad materials and/or moulding technique in a few batches is the most logical conclusion.
Reports of new cracks have just a bout dried up.
Most never developed cracks at all. And DJI offered replacement shells for those that did.
So trying to prevent something that's probably not going to happen is .......
 
If cracking was due to motor vibration or lots of other suggested causes, most P3s would have developed cracking.
But as only a very small number ever got the cracking, the theory that it was due to bad materials and/or moulding technique in a few batches is the most logical conclusion.
Reports of new cracks have just a bout dried up.
Most never developed cracks at all. And DJI offered replacement shells for those that did.
So trying to prevent something that's probably not going to happen is .......

Makes sense to me! And considering I got my P3P at the price drop I should have one of the later models, if they did in fact make any changes to the shells.

Thanks for the input
 
I got a P3S for Christmas. 3 months old, with approx 50 flights.. Last week i found a crack.
IMG_1192.JPG IMG_1201.JPG
I bought a P3P last week. Now im not so sure that cracks are such a rare occasion, because it happened to me. Im a little concerned for obvious reasons.. Im thinking about putting zip ties around all 4 arms by the base of the motors where the cracked happened. Im thinking it will keep pressure on em and hopefully prevent cracking in the future.
 
They work and do strengthen the entire prop area. I put mine on when it was really new and now after a couple of crashes the guards have really helped hold things together. I bought the gimbal saver, the carbon fiber camera saver and the motor reinforcement plates. Both crashes broke the camera mount and all it took was a quick application of gorilla glue and with in 10 minutes was back in the air with no problems. So all 3 parts really added a lot of extra safety features and saved me a lot of money. One of these days I will buy a new camera mount but the glue worked perfectly and it still works like new. So for me, they were good investments.
 
If cracking was due to motor vibration or lots of other suggested causes, most P3s would have developed cracking.
But as only a very small number ever got the cracking, the theory that it was due to bad materials and/or moulding technique in a few batches is the most logical conclusion.
Reports of new cracks have just a bout dried up.
Most never developed cracks at all. And DJI offered replacement shells for those that did.
So trying to prevent something that's probably not going to happen is .......
I bought the P3P 6 weeks ago and found two cracked arms on it today. One crack is on the bottom under a motor, and the other crack is on the top near the motor. It's only been flown carefully about 20 times, so I wouldn't say the reports have "dried up". Problem still exists.
 
The strongarms prevent major failure - motor separation during flight. The motor mounts can completely fail/crack and the strongarms will keep the motor 'bolted' to the Phantom.
If you already have cracks then the cracks will continue, but at a slower rate.

It's best to complain to DJI and have the lower shell replaced by yourself or send it in for warranty.
I live in remote parts of the world (Australia) so I asked DJI to send me the lower half. An hour later, she was airborne again.
 
With some of the reports on stress cracks, I was thinking about getting some motor mount reinforcements as a preventive measure. But do they really prevent cracking? If the cracks are due to motor vibration, how does putting a plastic plate underneath it prevent that? Looking for feedback

Thanks guys!
Motor mount reinforcements will definitely help reduce stress cracks. They will not harm if you use the right sized screws.

Have you ever thought why do you need washers along with nut-bolts? Washers are used on the bolt head side or the nut side depending on what is being stressed to apply pressure. These washers provide a smooth surface during tightening process and distribute the pressure over a larger surface. Same thing is being done by these reinforcement plates. Without enforcement plate, bolts directly tighten on plastic surface and excessive torque might easily crack plastic mounts or the weakest points.

Rule of thumb: Use them if you have them. You don't loose anything.
 
I bought the P3P 6 weeks ago and found two cracked arms on it today. One crack is on the bottom under a motor, and the other crack is on the top near the motor. It's only been flown carefully about 20 times, so I wouldn't say the reports have "dried up". Problem still exists.

I agree that the problem still exists, mine developed cracks after 20 odd careful flights. I think the reason the reports have stopped coming so often is that people are fed up with the poor after care service that they get from DJI so have just resorted to fixing the problem themselves.
 
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I agree that the problem still exists, mine developed cracks after 20 odd careful flights. I think the reason the reports have stopped coming so often is that people are fed up with the poor after care service that they get from DJI so have just resorted to fixing the problem themselves.
I would like to see if DJI has found a solution for stress cracks for P4 or everything is hidden behind the LED covers. Unfortunately I don't have P4.
 
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I would like to see if DJI has found a solution for stress cracks for P4 or everything is hidden behind the LED covers. Unfortunately I don't have P4.

I was just thinking the same about the P4, wondering if they had solved the problem. I think for something that is not cheap to buy, these things should be a much better quality than they are. Like said earlier in the post, because DJI are the market leaders in this field they seem to think they can get away with poor quality control & service. Makes you wonder how long until that theory comes & bites them in the bum.
 
Went ahead and ordered some. Seems like cheap insurance to keep from having to glue it up to soon.

Toph,

I've got them on two P3P's and I left the snap-on prop guard hubs (I don't use the prop guards) on my P2V+v3 as well (I still fly it every now and again) and I haven't seen any cracks. I did it for the same reason as you stated, I didn't think it could hurt to have them on. Just be kind of careful, particularly with the two screws on the end of the arm closest too the body of the craft and the one on the tip. Those are threading into plastic. Tighten them snug but don't torque them.

Jerry
 
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I got a P3S for Christmas. 3 months old, with approx 50 flights.. Last week i found a crack.
View attachment 47559 View attachment 47560
I bought a P3P last week. Now im not so sure that cracks are such a rare occasion, because it happened to me. Im a little concerned for obvious reasons.. Im thinking about putting zip ties around all 4 arms by the base of the motors where the cracked happened. Im thinking it will keep pressure on em and hopefully prevent cracking in the future.


I have this same exact crack. I super glued it and now I just watch it but nothing has come from it. I asked around when it happened and most say they have worse.


Sent from my iPhone using PhantomPilots mobile app
 
Definatly plenty of cracks appearing on new P3's.
Found one by motor mount screw on Sunday after 4th flight, nice and gentle, nothing hard.
Contacted dealer in UK (drones direct), after 3 days I was told to go direct to dji as was a manufacturing fault.
I've been dealing with dji since Wednesday and they've excepted it as a RMA.
Great, only problem is its gonna cost me over £80 to send it to the Netherlands.
E-mailed dji yesterday morning asking if there was any other option for getting this repaired, still waiting for reply.
Looks like reinforcement plates the best option at the moment
 
Just noticed 2 small stress cracks on the upper shell near the motors. Never crashed, always hand catch. And only had it a couple months. I'll be super gluing
 

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