Screw inspection = very bad day

[bighi]

A few people reporting this is not "too many". In the grand scale of things is a VERY small number. I know this doesn't help if you're one of them..Have you tried contacting support? If not I would try there..

You understand that there are over 100,000 in the air now? If it was a wide spread problem you would be seeing it pop up all over. Yes there are a few cases of it. DJI is looking into, they are actually requesting for the ops craft back directly for study.

On no Blade Strike. It's a lot more than you think. I have had stress cracks on every phantom I've owned with the exception of one craft. So I know what to look for. They are not that visible to the untrained eye. But these new ones on the screw holes between the motor area and lights are a whole new bag. In fact I did not even see them until the first poster in this thread put up a picture with a circular hole perimeter crack. I wasn't looking for those but the old classic motor mount screw hole to the shell seam crack. Trust me, not everybody is looking. Especially first timers who have never seen a phantom crack. If they all looked there would be a lot more noise. I would make a YouTube video explaining what to look for in order to help DJI get more accurate failure figures but my shell is already glued together. As I explained, I'm not looking for a refund. I just want DJI to fix this once and for all even if the phantom cost me 2000 euros to buy.

 

[blade strike]

On no Blade Strike. It's a lot more than you think. I have had stress cracks on every phantom I've owned with the exception of one craft. So I know what to look for. They are not that visible to the untrained eye. But these new ones on the screw holes between the motor area and lights are a whole new bag. In fact I did not even see them until the first poster in this thread put up a picture with a circular hole perimeter crack. I wasn't looking for those but the old classic motor mount screw hole to the shell seam crack. Trust me, not everybody is looking. Especially first timers who have never seen a phantom crack. If they all looked there would be a lot more noise. I would make a YouTube video explaining what to look for in order to help DJI get more accurate failure figures but my shell is already glued together. As I explained, I'm not looking for a refund. I just want DJI to fix this once and for all even if the phantom cost me 2000 euros to buy.

Then you doing something wrong.. Even with my pig p2 w/ h3-3d running lightbridge at 7000', I didn't developed these crack.(I was running lightbridge 3m before release, FYI) Now I have seen these cracks forum after people have disassembled their units and or applying liquid thread lock. Thread lock is the most common cause. Over tightening being a close second. This is why dji does not recommend users opening the craft.

The ops post is more than likely a manufacturing error with the torque being set too high on the assembly line. DJI is already in the process of getting this unit back for study.

 

[bighi]

Doing something wrong? I have not had a single crash, rough landing, anything with any phantom. 1, 2 and now 3. In fact reading about crashes from idiocy, mostly at tree top level, is getting out of hand. I fly mostly at 100 meter altitude and between 500 and 800 meters distance in P2, 500 to 1500 meters on P3. No crazy control movements. But anyway, go and dig up my posts. Look in there for any BS complaints from me about gimbal wobble, fly away, or on not level horizon. Nah, I don't post about that crap. But cracks after a few hours of crashes flying and soft hand catch landings is not right. Now if you tell me not to fly a phantom at design speeds because they cannot handle it, let me know.

This is the flying I do. As shown in DJI marketing videos. I see no difference.

 

[blade strike]

Doing something wrong? I have not had a single crash, rough landing, anything with any phantom. 1, 2 and now 3. In fact reading about crashes from idiocy, mostly at tree top level, is getting out of hand. I fly mostly at 100 meter altitude and between 500 and 800 meters distance in P2, 500 to 1500 meters on P3. No crazy control movements. But anyway, go and dig up my posts. Look in there for any BS complaints from me about gimbal wobble, fly away, or on not level horizon. Nah, I don't post about that crap. But cracks after a few hours of crashes flying and soft hand catch landings is not right. Now if you tell me not to fly a phantom at design speeds because they cannot handle it, let me know.

This is the flying I do. As shown in DJI marketing videos. I see no difference.

You never opened your craft or applied liquid thread lock? I can only go by what we see coming in and the reports that get logged. I'm telling you it's extremely rare compared to other things.

 

[happydays]

I'm glad to report that my UK delivered p3a is totally crack free.

 

[bighi]

Liquid thread lock? Why? I opened P2s to get access to the motor screw hole cracks. Then put it all back together at less torque than when opened and with the same screws as they were since there was always plenty of that blue stuff DJI had on the screws to begin with. As for the P3, why open it at all? The thing is brand new! And for what purpose anyway since it's a single board in there with everything contained in that board. In fact DJI should just bond the things together anyway if they plan on keeping use of the same thin plastic from the light area of the arms on. It would spread the loads throughout the shell instead of focusing all the stresses on two locations. I've said it before in this thread that the construction of the P3 internals is not modular. Any change of ESC requires a board change. Same for IMU. Only the motors wouldn't require a board change. But those never go before the ESC. All the light bridge componentry is external under the battery. So, yeah, the top and bottom might as well be bonded to relieve stress points.

As for the other things, man, I tell ya.... You could chalk a lot of it up to garbage in garbage out along with newbies flying a phantom with not enough rc craft experience. In fact you will see some posts of mine where I say that the absolute best gimbal and prop guards are a hubsan x4 mini quad for fifty bucks. Fly that well enough to never crash inside your house and you will never need phantom crutches like those guards. Crash into trees? Fly 30 meters higher than the trees. Scared of flying far? Get a mini quad and learn! DJI didn't put in light bridge so that folks go and crash into the tree next to the house. I've never had a firmware issue in any phantom. I fly over water, the Adriatic, 2 km out every day with VPS on at 120 meter altitude. In fact I don't buy more than half the complaints in this forum. But stress cracks are a different ball game. It's like hull delamination on a boat. The plastic should have never been so thin at the arms that it would subject itself to a need for such surgical attention to torque at assembly. Like I said, they never crack where the massive weight of the batteries and gimbal are. Cause its thick enough there. Build them more like eighties Porsches and less like seventies Lotus F1 cars is the solution.

 

[blade strike]

Liquid thread lock? Why? I opened P2s to get access to the motor screw hole cracks. Then put it all back together at less torque than when opened and with the same screws as they were since there was always plenty of that blue stuff DJI had on the screws to begin with. As for the P3, why open it at all? The thing is brand new! And for what purpose anyway since it's a single board in there with everything contained in that board. In fact DJI should just bond the things together anyway if they plan on keeping use of the same thin plastic from the light area of the arms on. It would spread the loads throughout the shell instead of focusing all the stresses on two locations. I've said it before in this thread that the construction of the P3 internals is not modular. Any change of ESC requires a board change. Same for IMU. Only the motors wouldn't require a board change. But those never go before the ESC. All the light bridge componentry is external under the battery. So, yeah, the top and bottom might as well be bonded to relieve stress points.

As for the other things, man, I tell ya.... You could chalk a lot of it up to garbage in garbage out along with newbies flying a phantom with not enough rc craft experience. In fact you will see some posts of mine where I say that the absolute best gimbal and prop guards are a hubsan x4 mini quad for fifty bucks. Fly that well enough to never crash inside your house and you will never need phantom crutches like those guards. Crash into trees? Fly 30 meters higher than the trees. On, I'm scared of flying far... Get a mini quad and learn! DJI didn't put in light bridge so that folks go and crash into the tree next to the house. I've never had a firmware issue in any phantom. I fly over water, the Adriatic, 2 km out every day with VPS on at 120 meter altitude. In fact I don't buy more than half the complaints in this forum. But stress cracks are a different ball game. It's like hull delamination on a boat. The plastic should have never been so thin at the arms that it would subject itself to a need for such surgical attention to torque at assembly. Like I said, they never crack where the massive weight of the batteries and gimbal are. Cause its thick enough there. Build them more like eighties Porsches and less like seventies Lotus F1 cars is the solution.

I fully understand the internals if the p3. I was asking a question. I'm trying to find the reason why you have seen this across multiple craft and MANY OTHERS have not. I had a total of 5 p2's all with hundreds of flights. 2 p2's with h3-3d / 2d, 2 visions pluses and a standard vision.

By the way the p3 has clips unlike the p2. So its not only the THREE screws securing the arms but very tight clips as well.

 

[snerd]

The fix...........................

Sorry, not funny for those it's happening to.


...........................

 

[blade strike]

Are you using any type of cleaner information or solvents on the shell?

 

[bighi]

You're right about those clips. But ask yourself this question. Did they put them there because the stress cracks on the P2 were so rare? I see those clips this way. One, they knew there were issues. Or two, along with the torx screws, they figured there is no need to open this shell with the new integrated electronics. Which I truly like, BTW. A lot less wiring and potential for failure. Not to mention better cooling. I'm not planning on ever opening any of my P3s. Not the one I'm flying or the one I have in the box. Right now I'm convinced that the P3 needs more material thickness at the arms. It's so thin that any person assembling has to have the attention to detail that a knowledgeable and caring owner with good finger feel has in order to achieve reliable and lasting results. By comparison you could have a chimpanzee torquing the center section of a phantom and there will never be cracks in that area. As for me, until I see some more inherent strength in that area, I'm flying a bonded top to bottom P3. It's much stiffer now and I feel no movement when putting battery in or out. Two flights in today and no more problems. Until its addressed, I'm flying glued. The result is just about invisible. Sacrificial shell though for those that mind.

 

[NJDroneDude]

During the installation of prop guards today, I was questioning just how how tight these screws should be. Anyone have a torque wrench to measure the inch/pound?
But here's the real kicker: Two days ago I received my p3 pro and noted that the shipping box was partially crushed, and the gimbal bracket was disconnected inside the box. hmmm. I took some photos just in case and for the record. Called the distributor and followed up with an email to log the condition. He said as long as the foam insert was in place, all should be fine. I was going to fly today but the weather n/g. To my surprise, another p3 pro was delivered to my doorstep. Once I finish my maiden flight, and all is satisfactory, I will return one of these birds!
Ps. anyone know why DJI uses torx and hex fasteners? It would be nice to have a standard.

 

[Nannerz]

more argumentative then investigatory.

Its a pissing match

 

[blade strike]

more argumentative then investigatory.

Its a pissing match

This is why we have requested silverstoned83 unit back and offered him a new one?

 

[NoOne]

This is why we have requested silverstoned83 unit back and offered him a new one?

Crap. I just noticed that hairline cracks are starting to form on my screw holes as well. Exactly the same shape as the OP's. I can see that these are going to open up in a few more flights. WTF.

42 flights with 9.5 hours of flight time. I hand catch and baby landings when I rarely do land. Never crashed it either. This is disappointing to say the least.

OP- How many flight hours were on your P3 when you noticed? I'm guessing we are going to start hearing a lot more of this as people start putting more hours on their units.

 

[deluge2]

<snip>
Ps. anyone know why DJI uses torx and hex fasteners? It would be nice to have a standard.

I for one am glad they don't use 'standard' fasteners, by which I assume you mean slotted or phillips-head screws.

Hex, Torx and also Robertson (square recess) fasteners are much more reliably installed and removed than phillips-head (slotted fasteners are very seldom used as they have no self-centering action). The angled tips of phillips head drivers, even if they're high quality and the correct size, have a very strong tendency to cam-out. This leads to excess downward pressure being applied in an effort to prevent camming out which can strip small fastener heads and cause the tip to shift and damage adjacent surfaces. Torx, hex, and square-drive systems are much less likely to cause these problems. For hex fasteners, the best drivers use hardened drill rod with tips ground to the exact dimensions. These fit much more snugly in the hex recesses and the heads are virtually impossible to strip when used properly. So, yeah, it's a little bit of a hassle to have the right sizes of the different options, but the worst thing is phillips-head with cheap drivers, truly a recipe for disaster...

Steve

PS: Checked my P3-Pro and my wife's P3-Pro. No fastener or shell crack issues for either P3. Also checked out our two old P2s and even the old P1. None of them had cracks either. Haven't had cause to remove any of the P3 fasteners. The P2s were each opened up a few times for various reasons, including curiosity. The P1 was opened countless times for maintenance and a series of modifications over the 16 months of its active use.

 

[blade strike]

Crap. I just noticed that hairline cracks are starting to form on my screw holes as well. Exactly the same shape as the OP's. I can see that these are going to open up in a few more flights. WTF.

42 flights with 9.5 hours of flight time. I hand catch and baby landings when I rarely do land. Never crashed it either. This is disappointing to say the least.

OP- How many flight hours were on your P3 when you noticed? I'm guessing we are going to start hearing a lot more of this as people start putting more hours on their units.

That is a far cry from hairline cracks. This is a complete failure. This unit was new by the way.

 

[bighi]

Crap. I just noticed that hairline cracks are starting to form on my screw holes as well. Exactly the same shape as the OP's. I can see that these are going to open up in a few more flights. WTF.

42 flights with 9.5 hours of flight time. I hand catch and baby landings when I rarely do land. Never crashed it either. This is disappointing to say the least.

OP- How many flight hours were on your P3 when you noticed? I'm guessing we are going to start hearing a lot more of this as people start putting more hours on their units.

I noticed it on mine at much less time than you so I know how it feels. You go, fly carefully, don't crash, hand catch, everything done with the utmost care while others are posting every day how to go about replacing gimbals after hitting the neighbor's tree. Sucks. You've got two choices. One is to send it in. The other is to do what I did which is explained in my previous posts. Whatever you do do not leave it in its current state. For starters, if it's the hairline crack thing just below the surface of one of the two screw holes between the motor mount and one of the lights, you've now got a lot more flex in that arm. Look carefully at other holes. Sometimes they are very hard to see unless you notice the extra flex there which reveals what cannot be seen as the craft just sits. I had two that were obvious and two that were barely noticeable but there. They could almost pass for mold release flash.

 

[bighi]

View attachment 23191

That is a far cry from hairline cracks. This is a complete failure. This unit was new by the way.

Yup, one of my four looked exactly the same

 

[blade strike]

Yup, one of my four looked exactly the same

View attachment 23193

It has to be torque on the assembly line, there is no way under normal flying conditions this can happen. I work with plastic all the time and this is not from normal wear and tear. I agree they could increase the thickness but this is excessive to say the least.

Are you guys using any kind of cleaners or solvents?

 

[bighi]

Others are so perfect in shape that they become far harder to notice. But they are there.