New motor mount screw hole to screw hole crack today. That's 3 out of 4 now. One more arm to go. I'll keep the glue ready.

What is mind boggling about this situation is the DJI attitude regarding this problem. By comparison, here is a story regarding a little problem I had with a boat I used to live on. Back in 2009 I picked up a Catalina 36 mk2 used. I don't even remember if it was under warranty or not as far as the installations but the hull, the structural, certainly was. With things that float or fly, structural is paramount. Anyway, I started having a recurring issue on the boat where the rudder would stiffen up a bit too much under load and one day it was enough that it wiped out my autopilot control board. So I left a message regarding what the best suggestion was for not having the issue happen again after repair. There was no longer a warranty on the autopilot at that point. Just hull, osmosis, delamination issue warranty. Next day I get a call from the owner of the company. Frank Butler. Born in 1928 by the way and the year was 2009. So a pretty old guy. He says, it's Frank Butler, owner of Catalina Yachts, tell me what you have problems with so that I can help. Then I can also give you some pointers on other things on that particular boat the we learned over the years. To put this into perspective, Frank Buter has built more sailboats than any person alive today. More units of each model than any manufacturer and maybe more units of any boat. He explained to me that while he trusts every employee to a high degree, he feels that only he alone should deal with problems on one of "his boats". I was blown away. He helped me sort the problem to perfection and even helped me improve the steering. One year later, while sailing to Catalina island from San Diego, I had a water pump go out on the boat which meant no sink or shower for the duration of the time away from the marina. I called Catalina and the said they would track down somebody affiliated with the company to bring one out to me if it coincided with their boat  outing. Next day Frank Butler himself called me and told me to dinghy on over to the beach cause he had a new water pump for me. He accepted no payment other than a couple of beers. Compare this to DJI. There is a lot to be desired with their arrogant handling of customers. You think that Frank Butler would tell me I was improperly balanced under sail? Or abusing the steering? Nah. Never. As he said, rudders are everything. They shouldn't break under normal abuse. Those same words.

just found my first stress crack! in the hole of the screw for the motor mount.

edbighi@gmail.c Posted at 2015-8-3 18:19
What is mind boggling about this situation is the DJI attitude regarding this problem. By comparison ...

Nice story i have to admit but lets be honest, the phantom is not in a pricerange of a boat and frank wang will definately not calling somebody like the old boat company owner. One thing is clear on the other hand, the phantom is the first 1400 euro product without a proper service and quality control i know of. Now i must help myself and order the costly 3D printed arm reinforcement kit because the product has a design flaw. Why not mass produce those arm reinforcement plates and dji send then to any P3 customer? Those would be really cheap to produce. In the meantime they could update their molds or change the plastic mixture a bit.

I think these are minor problems for most of us (until we have to send it in) but a MAJOR problem for DJI due to them not seeming to handle it properly.

Maybe it's just difficult to get the proper communication going? It's not the end of the world so one has to wonder why DJI doesn't just tell us the story....by now they surely should know about the causes and solutions (DJI has a lot of smart people working there).

They should offer a number of solutions - free shells and good instructions for those willing to do it themselves (assuming new shells are really better!) - maybe a reinforcement piece like those UAV bits - DJI could come up with something like that real quick....

And then perhaps lastly a more express service for those needing factory replacement. After all, these birds don't need the normal troubleshooting process, just the shell replaced. They could set up one or two employees to do nothing but those and that would likely get things down to 2 weeks.

Stuff like this baffles me because it's the perfect chance for DJI to show improvement but they don't come though.

Hello everyone.  I have a post that I hope will help some people out that wanna try to do something to help prevent cracks without voiding the warranty by gluing the two halves together.

I purchased my 1st P3P end of May 2015.  I had only about 15 flights on it when I started reading a bunch of threads about people talking about cracking.  I couldn't believe how many folks were talking about this and I never thought to look under the phantom (this being my first phantom model).  So, I took a look and low and behold, I had cracks on 3 of my 4 copter arms.  I couldn't believe it!  I never crashed it, never banged on the landing, didn't use any solvents or Loctite that everyone says weakens the plastic...I just flew the copter...again, less than 15hrs.

Here's a pic of one arm cracks:


Luckily I purchased this from a very good onsite store and I was able to return it for a refund and purchased a new one.

When I got the new one, I was gunshy about flying this thing without any precautions.  I didn't want to void the warranty, but didn't wanna leave it to chance, either.  So, the biggest item that made sense to me was the torque produced by the motors and the twisting of the body putting excessive force on the joining points of the top and bottom halves of the aircraft.....namely, the screw areas.

Here was what I have chosen to do and I now have well over 25hrs of flight time and no longer see any cracks appearing:
1) Went to my local HD hardware store (in the electrical section) and purchased PVC electrical tape:


2) I selected the white color to be more hidden on the copter (could have used the yellow as it was close to gold and could have given a unique look, too)

3) Here are the areas I actually added the PVC tape to:




4) I added PVC tape to all sides of the arms to strengthen the bond between top and bottome shell.
    I also wrapped a strip around the 'wrist' of the arms to also help with torque
    You'll also notice in my 2nd Pic I have clear gorilla tape noted - I flipped the bird upside down and cut a round piece of clear gorilla tape on the outer 'hand'
         of my arms as that is where my particular cracking occurred.  I put the gorilla tape over the screw holes and then just poked them with a small screwdriver
         so I could install the screws

I haven't seen any troubles and this is totally reversible, if need be.

Hope this post might help someone out!

Glueing the shell together will also kill the warranty and i doubt the tape will do anything to prevent it. What confuses me a bit is the fact that you have installed prop guards and those mounts should protect against cracks as well if the motor is screwed on that prop mount with longer screws. I wonder why you mention the weak tape and not your prop guard mount?

Daninho Posted at 2015-8-10 00:28
Glueing the shell together will also kill the warranty and i doubt the tape will do anything to prev ...

I'm going to make an educated guess and say that not all prop guards use all four motor mounting holes for attachment.

The set of removable prop guards I purchased have a mounting plate that is much thicker than the Phantom shell, plus they use a standoff on the upper surface that uses the Phantom mounting holes for positive alignment.

I bet that if the motor used both shell halves to mount the motors instead of just one, and properly torqued the fasteners from the start, that we wouldn't be having this discussion today.

Spheasant1
I have a single crack on black motor rear arm, where the top and bottom shells are screwed together.
I came to the same conclusion and remedy as you after twisting the arm with the crack and seeing the whole crack open up, with very little force.
I tightly wound 3 layers of tape around the motor arms as far outboard as possible.  Now when I try to twist the arm there is very little movement between the top and bottom shells the whole shell has stiffened up, and there is no longer any creaking noise when I flex the arms from the motor ends.  I'll see how long this lasts, hopefully no more cracks.  Good luck, and nice idea.

liningiv Posted at 2015-8-10 05:44
Spheasant1
I have a single crack on black motor rear arm, where the top and bottom shells are screwe ...

Certainly wish you the best.  It is too bad a number of us have to mod our copters to try and keep these cracks from either happening or getting worse.

Daninho Posted at 2015-8-10 00:28
Glueing the shell together will also kill the warranty and i doubt the tape will do anything to prev ...

I mention the tape because I had these same prop guard mounts on my first copter and 3 of the arms cracked.  I had the guards on since my very first flight.   Also, although I understand why you say the tape is 'weak' but the problem here is the two halves are not as one, so stress is not distributed appropriately to the top and bottoms of the shells...the stresses end up getting concentrated on the screw mounts...By applying the tape to the seams and also around the ends of the "wrists" you are essentially doing the same thing as everyone who discusses gluing the halves together without the voiding of the warranty issue.   This PVC tape is holding up quite well and I certainly notice a lot less ability to twist the arms with the tape on.

gregg1r Posted at 2015-8-10 02:49
I'm going to make an educated guess and say that not all prop guards use all four motor mounting h ...

You are correct on that one.  The DJI guards, I believe from the pics, only use the outer two holes.  Also, your theory on the both halves being used for the motor mounts is a good one!

I checked mine before when people started complaining about cracks and found nothing.

A few days ago I checked it again and three of the bottoms of the motor mounts have cracks in them. I contacted DJI customer service and I'm waiting in a reply.

zoti Posted at 2015-8-10 12:20
I checked mine before when people started complaining about cracks and found nothing.

A few days a ...

Wow that sucks, my third P3 should arrive tomorrow and I am hoping it won't develop cracks.

You have 3 P3s ?
I am really interested to ask why?
Have you had any cracks with No1 or No2 ?
I was crack free until flight 80, and 55 Km flown, no crashes or heavy landings, still on first set of props.  New set still in the DJI black bag.

Got stress cracks too now

2 arms.    have contacted dealer for warranty

About the stress cracks, Even if you get a replacement drone, og a new shell, I think the cracks will come again, if not DJI are making af new shell design of better materials. ??

Well I am almost done with DJI. I received my 3rd P3 today, and what do you think happen...?
The 1st P3 I bought was clean, it had no cracks until 16 hours of flight time, and it then developed cracks near the screw holes so I was like Okay no big deal I'll just get a replacement shell so I sent it back to dji and they sent me a replacement shell that they installed themselves, so after 8ish hours of flight time i couldn't believe it, but the replacement shell that dji put on my 1st P3 developed cracks again! Again! I called them and I expressed how upset I am and I asked why dji has not solved the problem! The person on the phone who was nice to me and could speak decent English told me that dji is working on the problem, they would send me a brandnew P3P unit after I showed them proof of cracks...etc so I was happy that They would send my a new unit to me, so now after waiting 2 weeks I received my NEW P3 and after I opened the box everything looked normal, and then I started inspecting the whole P3 for any damage... I looked at the screw holes and...... Beleive me or not, but IT HAS CRACKS. A new unit that already has cracks! Unbelievable. I called DJI during lunch and I was furious with them!, the guy told me to send it back in, I said No what for? So I can get a replacement shell and get cracks again!? He told me that's the only option right now. So I sent it back in today got a RMA I am going to get a refund and I am going to wait 1-3 months to buy another P3. I told them I'm done with DJI right now. I asked the person why hasn't dji fixed this massive problem, he had no answer for me. Completely unacceptable DJI! I would expect better. Ever Since dji released the P1, P2/+ and now the P3, they have NOT FIXED THE PROBLEM YET. Mr. Wang needs to wake up. I wonder if the P3 standard will develop cracks, wait what am I saying? Of course it will.
At least I still have my P3A it does not have any stress cracks yet. 9 hours of flight time and counting.
Here are some pictures :

These guys are unbelievable! A new model launched every other month but absolutely no effort in rectifying this problem.

Jack57 Posted at 2015-8-12 02:26
Well I am almost done with DJI. I received my 3rd P3 today, and what do you think happen...?
The 1s ...

Yes but it was clear to me that a repair at DJI has no sense because the shell is still the same, thats why i will use the strong arm kit. Its clear that they havent changed their shell in this short period of time, this takes ages to building new molds and new plastic mixtures etc... The P3 will probably never get new shells because they dont have the time, its more likely that that P4 will get them. I expect a total different shape from the P4, the Phantom design is getting to old now. Maybe something more premium for the price like carbon fibre.

Ive read that someone got his P3 back and they repaired the cracks with something. Maybe thats what they will do until the P4 arrives

Daninho Posted at 2015-8-12 04:35
Yes but it was clear to me that a repair at DJI has no sense because the shell is still the same, t ...

I don't think you'll find carbon fiber shells from DJI as a stock delivered item.

Being involved in the aerospace materials market for quite a few years, there are two way to fabricate this shell. One would be injection molding after fiber placement which brings problems of fiber washout or hand lay up which adds huge cost, even with Chinese labor rates. The cost of an 8 harness graphite cloth is probably twenty times the cost of the present plastic used.

Check out mil handbook 17 for some idea as to the types of designs various graphite materials can be formed into.



Until DJI is able to tie the upper and lower shell halves together to spread the motor torque to both halves, the Phantom shell is going to crack. Just replacing a plastic material with a graphite fiber isn't going to fix the problem.

gregg1r Posted at 2015-8-12 04:52
I don't think you'll find carbon fiber shells from DJI as a stock delivered item.

Being involved i ...

You got me wrong, of course DJI cant produce shells made of laminated carbon fibre sheets, that would be super costly to do when they bake carbon shells. I said i hope a Phantom4 is more premium buIld like a mini inspire with carbon fibre as a tube frame or something like that and a plastic housing. Or just a higher grade of plastic if its another plastic shell copter. Maybe this type of polymere guns were made of. Its molded polymere with nylon for example or glass fibres. This is the stuff weapons like the glock pistol are made of. This stuff is cheap but super strong. That would look premium as well and more like a tool instead of a toy,

As I have posted previously, just tie wrap the end of the arm and you should be good to go.
http://www.phantompilots.com/thr ... /page-2#post-448278

fredsheldon@aol Posted at 2015-8-13 02:45
As I have posted previously, just tie wrap the end of the arm and you should be good to go.
http://w ...

Sounds good Fred. May I suggest that the next time the side view mirror on your car gets damaged, that you duct tape and tie wrap it back on?

If I go to sell my Phantom 3 Professional, don't you think that the prospective buyer might want one that isn't damaged? If they themselves want to tie wrap the shell that's their business.

I don't have any cracks.  but my god... if a crack in your phantom has people this worried???  i don't know what to think.  get some crazy glue and reinforce the crack and move on with your life.  lol   

gregg1r Posted at 2015-8-13 03:14
Sounds good Fred. May I suggest that the next time the side view mirror on your car gets damaged,  ...

Or drop it off at the garage to be fixed, waiting 2 months to get it back for a broken mirror?

EpicDroner Posted at 2015-8-13 05:03
I don't have any cracks.  but my god... if a crack in your phantom has people this worried???  i don ...

Those cracks will get bigger and bigger and when you use glue you have to open the shell and loose all warranty, so not a good idea.

gregg1r Posted at 2015-8-13 03:14
Sounds good Fred. May I suggest that the next time the side view mirror on your car gets damaged,  ...

The tie wraps will prevent or stop the cracks from getting worse. If you want to sell you just remove the tie wraps. I have no cracks but wanted to do everything I could to prevent them from ever appearing by strengthening the area in the hopes of reducing the twisting action that is causing the cracks in the first place. What harm in that

my p3pro has cracks after about 50 flights. 45 days old from bhphoto.

There are shells you can buy at your drone store in about to purchase a couple before they run out because I don't want to be waiting  for dji to ret mines

liningiv Posted at 2015-8-11 02:48
You have 3 P3s ?
I am really interested to ask why?
Have you had any cracks with No1 or No2 ?

Yup....mine is the P3P

fredsheldon@aol Posted at 2015-8-13 02:45
As I have posted previously, just tie wrap the end of the arm and you should be good to go.
http://w ...

I really like this idea, too!

Daninho Posted at 2015-8-13 21:59
Those cracks will get bigger and bigger and when you use glue you have to open the shell and loose ...

In addition, for a $1300 piece of equipment to have cracks within a month of flying as advertised, that is ridiculous. This isn't a $100 item.

Just found this post and inspected closely my brand new Phantom 3 Pro. Did not see anything and decided to take photos with a camera. When looking closely at the hires pics, I can see at the base of one of the last 2 screws at the end of the arm (just before the 4 screws fixing the motor), a very small crack.

From what I see, it lookds like they have over screwed it. They may have or had an issue in factory not respicting correct torque when putting the screws in place!... TOO BAD! QC Issue...

ppkessler@free. Posted at 2015-8-20 02:53
Just found this post and inspected closely my brand new Phantom 3 Pro. Did not see anything and deci ...

Honestly, i never saw a P3 without that imperfection or weak point in one shell screwhole. I guess its a molding imperfection in one screwhole. I don think its to tight because its only one screwhole. I guess all shells until a certain date have that, maybe they are still using the shells. The only thing that scares me is that i saw shells with cracks around the motorscrews as well which dont have this imperfection from factory.

Agree. So I will continue to use it but hope that if that amplifies DJI will admit the defect within the warranty period knowing the history around that...

Tahoe_Ed Posted at 2015-7-13 02:00
You are seeing 28 users of over 100,000 in the world.  That is not a significant number.  We have  ...

Tahoe Ed, Seriously, you are not helping the Company's reputation or image by taking a stance against your customers.  You should be sitting back and listening.  there is a lot of good information being thrown out here and some of it is in the form of FREE R&D from some pretty talented people.  

This is sort of a rich man's hobby at your price point so I am suggesting the majority of your demographic is well educated and intelligent.  Don't pi$$ them off.  I myself run a 1.5 billion dollar organization and know a little about Customer Service and I bet there are others much more educated and responsible than me on this forum.  With all due respect, you need to STFU....  this is just my Humble opinion and it's a free world.  This advice is worth exactly what you paid for it..

Now,  After the strong rebuke to the DJI Staffer (who may be the owner for all I know..), I have to say that Ed has a valid point in that we consumers come on to a forum to either gain knowledge or find a solution to a problem.  I would assert that the vast majority of the members on this thread probably got here because they typed it in as a search to learn about or because they were experiencing the issue, or had heard about it.  This is not an unbiased sampling of consumers, ergo, not a valid representative percentage of owners experiencing cracks.

THAT being said, there are CERTAINLY enough complaints to address the problem with remorse and urgency to keep your patrons happy.   I suggest you do so.  Repeat customers cost you NO ADVERTISING DOLLARS and in fact sell you more product than your advertising since you are in such a niche market.  

As stated above there are a lot of smart engineers on this forum and you could make this a positive by having your enthusiast involved in the solution as opposed to defending an indefensible position.

Stepping off the soapbox now...

Oh, and I just bought my FIRST DJI product and it is arriving today (8/21). It's a P3a and I am looking forward to enjoying it sans cracks....  I hope that will be the case.

gregg1r Posted at 2015-8-10 02:49
I'm going to make an educated guess and say that not all prop guards use all four motor mounting h ...

Good point.  Has anyone who is using Removable prop guards experienced cracks during use?

and obviously we know the #1 is a bit of a lie, so take off %50 off of that result

Honestly thought everyone in the crack club was a bit crackers, but had a look and sure enough, have a cracked screw mount (the in - the - hole crack).

Pity, think I'll just zip tie the arms, unless DJI offer to send out new shells. Don't fancy being without my toy for 4-6 weeks + postage.