REBELimgs Posted at 2015-7-10 03:52
I just opened the box to my new P3P a few hours ago and I have yet to fly it. The battery still isn' ...

This make Ed smile.  This is exactly what mine looked like the flight before it cracked.

Tahoe_Ed Posted at 2015-7-10 08:17
I did not say that.  An issue is an issue if it effects you personally.  I disagree this is more th ...

Yes, well 6-8 weeks to get a repair isn't going to fly with most people by the looks, which is why people are discussing workarounds and fixes themselves. Understandably.

I will cost me much less to tend to the stress cracks myself, than package and send this back to the US from Australia, and the turn around time is much faster.

I don't know what your stats are, but they will likely be as skewed to benefit DJI as this poll is skewed to go the other direction.

If you were taking this seriously I would think that DJI make a formal announcement to have all users check for cracks - this could possibly be a serious safety issue, could it not? Are we not doing the right thing by worrying about structural defects?

REBELimgs Posted at 2015-7-10 03:52
I just opened the box to my new P3P a few hours ago and I have yet to fly it. The battery still isn' ...

Yeah, you can see the outline where it will probably crack (unless you never fly it). Pretty thin there.

So what are you going to do?

Are the crack found on the crews that holds the shell together ?  If so, its not a biggie... unless its the ones that holds the motors,,,

I think P3 needs a new shell after a certain flying hrs... just like real plane .. it getting some material fatigue..

I better wait for some 3rd party reinforced shell..

mtnmaddman Posted at 2015-7-10 08:31
I have to smile when I see users that have never flown their P3's and say they have cracks

This n ...

I have not belittled any of our customers.  If you believe that pole you are not looking at the facts.  I personally know of about 20-25 units with the problem reported on the forums.  Remember users cross post in more than one forum.  If it were 25% DJI would be inundated and they are not.  I have email conversations with China almost daily.  We communicate your concerns and they respond back when they have a solution.  I don't want to minimize the pain that those who have the problem are feeling but at the same time, I am not going to yell fire in the theater either.  

So they have found a solution.,,have the customer to do something they don't like.  Too bad, it's the way it is.  How many businesses stay in business by making the customer feel bad?  I never talk to my clients this way.

The shell has two points of fixation next to the motor mounts.  Those are the ones that are breaking.  When they do, it allows translation of the shell and furthers the crack.  The next point of fixation between the arm is half way down.  It is a #8 torx screw, but it doesn't have a machine thread.  More like a standard wood screw.    What there needs to be is one more fixation point on the arm.   Making two.  The two fixation points by the motor need to be thicker where they curve into the shell. Externally, that's the area showing fracture.   
For now.   Loosen the two screws in the recessed holes.  Not the 4 motor screws.  Re torque them but don't get aggressive.  They have blue Loctite on them, so they should stay put.  

Next,  tighten the screw in the middle of the arm.  How tight? Torque the end of the arm to see if there is movement in a rotational way. If you get the middle screw right, the rotational torque on the arm should decrease if not stop and make it rigid.  This will help translation of the shell pieces and hopefully prevent the two fixation points near the motor from fracturing.  I noticed I had a lot of play from the factory between the shells and along with improper application of the screws near the motor or poor design, they cracked.   I would tune each arm by tightening the middle screw in the arm until there's no rotational torque on the arm.  Rotational torque means shell translation, which means movement at the two standoffs by the motor. Which means fracture.  They could solve this by making one more fixation point in the arm or having a notch where the two pieces come together where they can't translate.  People putting zip ties next to their motors get this.

If you already have cracks,  you will have to fix it yourself by gluing the standoffs internally or sending it in.   Or using a new shell......oh wait,  we are not smart enough to do that on the phantom 3.  

SectorDrone Posted at 2015-7-10 09:37
Are the crack found on the crews that holds the shell together ?  If so, its not a biggie... unless  ...

It is a huge biggie, As a structural engineer, the integrity of the radial parabolic torsion box that the screws hold together is where the arms gets it strength that enables it to hold the motor and absorb torque factors.

When the compression factor, and fitment of the shell halves, is compromised the upper part of the shell becomes useless, defeating the engineered shape of the T box, a degradation of of the engineered strength of about 80%.

The entire forces exerted by the motor are now mostly on the bottom shell half. the constant twisting forces exerted by directional change of any sort, trying to cancel the gyroscopic forces created by The spinning motors, and props will be working the bottom shell constantly.

I totally agree that an aftermarket shell or fix will likely be the most viable solution.  Aftermarket folks have saved more than one companies butt.

mtnmaddman Posted at 2015-7-10 10:25
It is a huge biggie, As a structural engineer, the integrity of the radial parabolic torsion box th ...

I'm glad you understand this.  Any play between the shells allow the upper shell to take on less and the bottom one more.  The bottom shell, being attached to the motor, moves more and sheers off the posts if they are cracked already from the factory.  Bad design.  You have to get the shells intimate and the only way to do that is tighten the middle screw in the arm more and maybe use a zip tie, like others have suggested.   Or you can spot bond the shell but i doubt that would hold and only cause chips at the bond points

InspirelessAggi Posted at 2015-7-10 10:42
I'm glad you understand this.  Any play between the shells allow the upper shell to take on less a ...

"You have to get the shells intimate"

I like that terminology, maybe people will understand this eventually. I have a temporary cure fix suggestion that will not adulterate the shell, until an acceptable solution is proposed by dji.

I would take a couple of good zip ties per arm and cinch them up around the arms at the compromised screws I would  have the lock part of the ties down. to try to control my ocd.  I would super glue the lock part of the zip tie only, they could be removed if nec.  

I would then wrap them with tape,  you could use colored auto striping tape, Wouldn't look to bad, would all be removable and would not compromise warranty.  This fix would last until dji offers an acceptable solution.  I think you could fly your P3 safely in the meantime.

Cut the excess tie off and use epoxy in the slip lock part, instead of super glue.  Super glue would likely get on the shell

mtnmaddman Posted at 2015-7-10 11:02
You have to get the shells intimate

I like that terminology maybe people will understand this ev ...

Guys,   Take your fingers and grab the end of the arm and try to rotate the arm about its center axis.  If you have too much play, try to tighten the screw under the middle of the arm.   If you can't, zip tie the ends.  Like stated above,  it should help.  

My arms are pretty solid now.   Much more so than from the factory

guy.keren@gmail Posted at 2015-7-10 05:14
I see.....

This is what I just found:

This is good ideea. I might try that with BONDIC which I will get later on.
But this requires me to void the waranty by opening the P3...

ScottyT Posted at 2015-7-10 08:53
Yeah, you can see the outline where it will probably crack (unless you never fly it). Pretty thin  ...

There isn't much to do. I just got this one after dealing with an issue with the last one. I'll keep following threads like this I suppose. I've invested quite a bit into this thing (in addition to the cost of the phantom itself). I'm going to fly it, is what I'm going to do.

If it breaks then I'll have to get in contact with DJI, I suppose... That or wait to buy another shell.

DJi should redesign this shell before replacing.
Service operation is about month without flying for a customer. Time is money for most people. Most of phantoms are used not for fun but for work.

Horrible shell quality, the question is not 'will' but 'when' it crack.

This is not only crack on shell. This is crack on trust.

Tahoe_Ed Posted at 2015-7-10 07:24
I just turned my P3P upside down.  I fly this thing all the time and I am not gentle with it.  I hav ...

No offence mate, but if you do not see the cracks on this brand new, not used Phantoms then you should buy a glasses.
This is not fun to smile. These people put a lot of money in DJI product, so this is normal when they expect a quality.

almost 20 flights after me,
no issues ... no crashes, since last flight no cracks.
now I can see white mark on one of screw holes ... it comes,
I'm sad ;) will use warranty but this is really bad ... even cheap 100 $ drones are not affected by those kind of issues.
sorry for picture quality,

I have less that 20 flights and i have a screw shell that's broken free already,  and on the top of the shell i have a screw base that has broken free as well,   the screws were ridiculously tight when i opened it up.   

However there is no way im sending mine in for repair and waiting months for service in canada,  il just epoxy the whole thing and move on.  

Looks like we added a few more people who found cracks since DJI thought that only 20 people had this problem.  I'm sure DJI knows this is a manufacturing problem.  They just don't say it publicly because you know, lawyers.  They have them in China too lol.

stu_nb@hotmail. Posted at 2015-7-10 22:21
I have less that 20 flights and i have a screw shell that's broken free already,  and on the top of  ...

Wait 8 weeks just to get another cracked defected shell.  No, thanks.  Either way you have to open the shell and reinforce it yourself and void the warranty.  So we are caught between a rock and hard place with DJI.  Awful customer service.

stu_nb@hotmail. Posted at 2015-7-10 22:21
I have less that 20 flights and i have a screw shell that's broken free already,  and on the top of  ...

Can you post pics of your damage, when you get a chance? Are these on the inside rear screw holes?

azdevv@gmail.co Posted at 2015-7-10 22:43
Wait 8 weeks just to get another cracked defected shell.  No, thanks.  Either way you have to open ...

I wouldn't open and void warranty just yet, several wraps of strapping tape or a couple of zip ties and tape will hold it until this is resolved, There are many ways to fix this some voiding the warranty and others not.
two wraps of strapping tape and a zip tie and it will not come apart.

Good niche for aftermarket crack-free shells. There is not much to do to improve it.

ScottyT Posted at 2015-7-10 22:54
Can you post pics of your damage, when you get a chance? Are these on the inside rear screw holes?

Mine are on inside rear screw holes and most that I've see are too.  But according to DJI, it's pilot error, not a manufacturing defect.  LOL LOL SMDH

mtnmaddman Posted at 2015-7-10 23:01
I wouldn't open and void warranty just yet, several wraps of strapping tape or a couple of zip ties ...

I'm not opening mine right away.  I don't wanna send my P3 on vacation for 2 months only to have DJI start offering to send people a new shell or something more logical.  I will open her up to reinforce further once I'm closer to the end of warranty periods.  

azdevv@gmail.co Posted at 2015-7-10 23:13
Mine are on inside rear screw holes and most that I've see are too.  But according to DJI, it's pi ...

A DJI rep didn't tell you that, did they?!

The traditional solution to this kind of cracking in plastic/screw interface design is to cast metal inserts into the plastic part.  DJI could cast threaded metal inserts into the shell pieces.  This would eliminate most of  these crack issues.  And perhaps adding a few more support ribs or increasing the thickness of the plastic in strategic points might help.  (Or use a better material if possible.)
Would threaded inserts solve the prolblem? Yes.

Would threaded inserts add cost? Yes.  (A few Pennies.)

Will DJI ever go to the trouble to add threaded inserts?  Not likely.

Guys,

this is not rocket science,
as mentioned earlier I have one white mark showing that crack is appearing and I can already see this is caused by twisting force of motors / propellers that are mounted with some reduction angle to prevent VRS



we have here design issue & for sure poor quality material used for shell.
not sure how this can be fixed but for sure DJI should take this into consideration and confirm next steps for affected users ... we are not talking about 100$ drones ;)

ScottyT Posted at 2015-7-11 00:27
A DJI rep didn't tell you that, did they?!

No, not at all.  But the employee in this thread seems to be in denial that it's a manufacturing defect so it must I'm just flying it too hard lol.

Tahoe_Ed Posted at 2015-7-10 08:17
I did not say that.  An issue is an issue if it effects you personally.  I disagree this is more th ...

yes this is a nice solution BUT is it 100% sure that i get "revised" shell this time without those flaws? Or do i get just the same old design again and i have maybe again cracks after some flights? Many ppl have cracks and even more ppl have those strange stress marks right from the box, the same stress marks you get when you bend plastic a bit. From those stress marks larger cracks will probably develop sooner or later.

I personally wouldnt care if the security is not affected but the problems start when i will sell it on ebay for the next generation, ppl will send it back to me because of cracks.

mtnmaddman Posted at 2015-7-9 20:47
You can turn down the braking action, I think,  in the pilot app. If you can, I would strongly sugge ...

As of today, the poll had 32 people saying they had cracks.  That may be 25% of the folks that responded to the poll but not that many compared to how many units were sold.The survey itself is unscientific and who knows what the margin of error would be.  The results cannot be extrapolated over the entire sales numbers.

Rigworker Posted at 2015-7-11 02:21
As of today, the poll had 32 people saying they had cracks.  That may be 25% of the folks that resp ...

It really doesn't matter.  32 people standing in a room holding phantoms would be 32 pissed off people wanting it fixed.  The number itself is what speaks to the final product.   If I sold 1000 products and 10 people had problems, I would take,care of the 10.  I'd take care of the problem if it were one.   The purpose isn't to be scientific.   More to gather data on the number of uncrashed mechanical failures.   Not even DJI could get appropriate  figures in such a short period of time.    They would have to get actual repair numbers over a period of a year.   

If 32 people  had problems,  DJI should and is concerned.  There's no percentage that is acceptable for a factory defect if you run a good business and care about your products and stand behind them

Or look at it this way.  If 32 people bought the advanced version.  That's 32,000 dollars spent on units that have uncrashed mechanical failures.  The actual number is 29.  I guess you are counting crashed cracks

Rigworker Posted at 2015-7-11 02:21
As of today, the poll had 32 people saying they had cracks.  That may be 25% of the folks that resp ...

Many will not notice ... I can only see after detailed check that crack is starting
... % of probe here on forum can give some idea what is the global % of affected...

musman1978 Posted at 2015-7-11 02:44
Many will not notice ... I can only see after detailed check that crack is starting
... % of prob ...

I agree,  Though what the pole,  the post responses, and the very short length of time that the p3 has been out.  is telling me that this is a big problem.

An old guy that poured concrete all of his life once told me,  that there is only two types of concrete,  concrete that is cracked, and concrete that's going to crack.

This is the same thing they are all going to crack at some point.

I have such a thing at home Purchased at DJL And now what do I do ?

CodeR Posted at 2015-7-11 04:13
I have such a thing at home Purchased at DJL And now what do I do ?

you have two options,

1. contact DJI directly (open ticket, send pictures) wait for reply and send to DJI directly ...
2. contact your dealer and ask for warranty fix - you can also point to this thread on DJI Forum so they will not tell you this is not covered by warranty.

in both you will  be minimum 1 month without P3 and there is a chance you will receive fixed or new unit with same crappy shell that will crack after some time ... but warranty for shell will restart

keep us updated.

musman1978 Posted at 2015-7-11 04:30
you have two options,

1. contact DJI directly (open ticket, send pictures) wait for reply and sen ...

You can write me pw
możesz napisać mi pw

CodeR Posted at 2015-7-11 04:37
You can write me pw
możesz napisać mi pw

I think PM are not working,
ping me by email piotr@musial.waw.pl

ALL sorry for offtopic on this thread.

As we can see there is high risk of shell crack, and in this situation DJI should call their all P3 customers (they have got e-mails after drone registration) for service action - change defective shell for redesigned and corrected one. Many of customers are not aware this issue.

@ Tahoe_Ed

Stands on a German website that it is resonant vibrations which destroy the actual body. These resonances occur at certain engine speeds. May cause actual results, which is un- stable the structure of the housing, and even hit the propeller on his arms.

Source: http://www.kopterforum.de/topic/35079-überprüft-eure-gehäuse/page-3#entry525007


Resonant vibrations are strong, like this (starts at 1:06):

Hmm.. interesting. So it is on some engine rpm, maybe it coul be avoided by firmware in some way.... but it dont explain cracked and out the box brand new phantoms :/
I have my own and not confirmed theory. Damage looks as caused by rotational force. This force can apply in both cases:
1. In facility - a worker is using electro-screw with assigned Nm, and this fast screwing can cause similar damage.
2. In flight, when the screw is strong tighten the shell cannot 'work' when phantom is flying, and then the upper element screwed to the uppershell is not moving and bottom element of shell is trying to rotate and then finally wring fixing.

And there is a two or three guys with shell unscrewed and screwed gently (before first flight) by a hand without cracks. It can mean the shell can 'work' when is under pressure without dmg.

By a 'working' shell i mean the upper and lover modules are not very strong tighten and they can make a little moves by themselves when they are under pressure.

Maybe my words are not good selected, but i think you know what i mean. Of course i can be completely wrong.

mtnmaddman Posted at 2015-7-11 03:36
I agree,  Though what the pole,  the post responses, and the very short length of time that the p3 ...

I'm somewhat anal about things I build for me. I do lots of research and have a heavy materials background.

When it came to building my new workshop last year, I researched the best proven methods to reduce or eliminate cracking in concrete.

My solution was a monolithic pour. My footers are 24" deep by 24" wide with a 45 degree slope joining into the floor which is 10" thick. I used 4000 psi concrete with fiberglass reinforcement. The entire "pad"  was poured on a bed of 22 tons of #57 stone that was vibrated to compact and allowed to sit for two weeks before the concrete pour. This was covered with 10 mil poly to keep the moisture in the concrete instead of being absorbed into the ground.

I poured 26 yards of concrete in about 4 hours and used a sugar solution that retards surface cure to allow for the concrete to cure from the inside out.

You can make concrete crack proof provided you have the time and money to do the job right the first time.

Now getting back to the Phantom 3. Does anyone have an idea or know if the stand-offs that the screws attach into for securing the shell halves touch one another or if there is a gap between? Has anyone used a countersinking tool on the screw holes to remove any of the stress risers either on the motor mounting or body attachment holes?