I Can't Believe it! MY "New & Improved" shell has a crack after 7 flights!

[Chuck Young]

After DJI "fixed" my quad because of stress cracks around the rear motor mounts and sent it back to me a few days ago, I inspected it yesterday and noticed this crack on the arm after just a few flights!

And this crack is on the arm itself and not in the screw mounts.

All 7 flights were flawless and the landings were all hand caught.

I handle and treat my quads like a new born baby!

The old "flawed" shell lasted much longer than this.

Man...this is ridiculous!

Anyone else had a new and improved shell crack?

Have you sent it back yet?

 

[III% Streve]

I was secretly hoping that you would see his post and reply. ;-)

I guess Im the designated a-hole? Thats OK.. Im a professional! I get that there can be varying opinions. But some people, sometimes... they just have no grasp on reality. No basic comprehension on ANY level of physics., and even seem at time to have no idea what it is thats happening to make something fly. Those people are fine too! Its when you have one of those that at the same time has no ability to learn. THATS when I wish there was some way to virtually deliver a smack to the back of the head!!

 

[CONTROL FREQ]

Have you sent it back yet?

not yet.

i'm going to find some time in the next week or so.

 

[Oso]

I guess Im the designated a-hole? Thats OK.. Im a professional! I get that there can be varying opinions. But some people, sometimes... they just have no grasp on reality. No basic comprehension on ANY level of physics., and even seem at time to have no idea what it is thats happening to make something fly. Those people are fine too! Its when you have one of those that at the same time has no ability to learn. THATS when I wish there was some way to virtually deliver a smack to the back of the head!!

Sorry no, that's not what I meant. You are very knowledgeable and your replies are just usually more entertaining than many. Along with helping people, you add some personality to the forum that was missing during your recent hiatus from posting.

 

[CONTROL FREQ]

I will definitely balance them on a Du-Bro 499 before I fly (you must get the P3 balance rod to work with the Du-Bro)

are you saying that I need to buy a special rod for the phantom for the Du-Bro to work properly?

 

[III% Streve]

Sorry no, that's not what I meant. You are very knowledgeable and your replies are just usually more entertaining than many. Along with helping people, you add some personality to the forum that was missing during your recent hiatus from posting.

Thanks! I appreciate that a lot.

 

[Dounin Front]

are you saying that I need to buy a special rod for the phantom for the Du-Bro to work properly?

Yes, the Du-Bro 499 does not come with a balance rod for the P3. The included rods are for prop hubs open at both ends. The Phantom hubs have a hubcap and blind threads. The balance rod for the P3 has threads at both ends, CW and CCW and is readily available on the same website.
I bought the Speedy Prop Balancer for P3, but after watching videos of the Du-Bro, I've decided to get the Du-Bro. At least I won't need to buy another P3 balance rod.
Try using electrical tape for balance under the prop. It's pretty heavy so a little will go a long way. The adhesive is also superior and does not leave residue.

 

[Oso]

are you saying that I need to buy a special rod for the phantom for the Du-Bro to work properly?

Maybe try what I replied to you yesterday while you wait for your Du-Bro. It works well and should give you an idea if your props are not balanced.

I Can't Believe it! MY "New & Improved" shell has a crack after 7 flights! | Page 2 | DJI Phantom Forum

 

[Dounin Front]

Maybe try what I replied to you yesterday while you wait for your Du-Bro. It works well and should give you an idea if your props are not balanced.

I Can't Believe it! MY "New & Improved" shell has a crack after 7 flights! | Page 2 | DJI Phantom Forum

Oso - Your granite countertop idea is a good one, but sadly I don't have an exacto knife and the prop will not fit my utility knife (ha-ha). The Speedy Prop tool is similar to your idea where the balance rod rolls on 2 steel wires (like the granite). This method is completely dependant on the surface being absolutely level. Your countertop probably meets that criteria. My workbench does not so I built a little platform for the purpose on 3 adjustable legs (screws) to put the prop balancer on or my P3 on to calibrate the IMU. I have a digital level--I tried using my iPhone, but it doesn't pass the ball bearing test for accuracy.
What I like about the Du-Bro is the balance rod rides in a groove formed by 2 overlapping discs at each end. The rod just rolls in place instead of along the counter. I found myself doing too much fussing to keep everything straight using the speedy prop.
So we'll see. The funny thing is I'll probably never use it again after I get the Dji CF props balanced.

 

[FredzMaxxUAV]

Most people add a little weight, near the hub on the back of the light blade. You can use tape or paint on a little paint or epoxy. I don't like to sand the heavy blade as it risks changing the aerodynamic character of the blade if you are not careful, and can make the blade pretty thin.

Where exactly would you put the tape? And what tape? Pics?

 

[fastsmiles]

The cracking may be due to the twisting motion that the motors are putting on the shell. This crack especially looks like it is from twisting of the arm.

 

[Dounin Front]

Where exactly would you put the tape? And what tape? Pics?

I'm a fan of electrical tape because it sticks well and is fairly heavy so you can use small pieces placed on the underside of the blade. Perfect for CF blades, but if you want to color match, you might use something different. Don't push it on tight till you are sure you have the placement right.
The mfgs seem to recommend adding weight rather than removing it. I guess they don't trust us.
Apparently hub balancing is a thing also. You might get the blades to balance horizontally, but if the hub is a little heavy in vertical plane, it will rotate to the bottom. Then you put a little weight on the light side of the hub. So I'm told.

 

[Dounin Front]

The cracking may be due to the twisting motion that the motors are putting on the shell. This crack especially looks like it is from twisting of the arm.

This whole crack business is really everyone's guess. I personally have no cracks yet, but my P3 did hit and fall from a big tree in the first 2 weeks I owned it. (totally my fault) The damage was great enough that the motor area of one of the arms actually twisted and crimped the plastic. There were no shells available at that time so I separated the shell, took the motor off and straightened things out with a vice and a hair dryer. The prop was touching the fuselage when I started and nearly straight when I finished. It ran perfect and still does 6 months later.
My take away from this experience is the shell material is very flexible and relatively unbreakable. There was no permanent damage after all the bending and straightening.
So, my guess, by way of elimination, is that vibration may be a more likely cause for damage than flexing or heat. Or QC in the mold process where they end up with some thin spots once in awhile.
BTW: I think the StrongArm motor mounts that are spammed below your comment are probably a very good idea.

 

[2raaas]

I thought the cause of the cracks was due to the motors not sitting right and the reinforcement of the arm? The new motors sit more flush whereas the old ones dont, hopefully they will put new motors in a new shell and you should be ok.

 

[Wibble]

Chainsaw vibrations?? Really? Are you REALLY that far out of touch with everything involved here? a FART vibrates too! So why are chairs not cracking? I needed a good laugh! But thats about the worst drunken post Ive ever seen on the internet! At least I hope thats what it was.

That far out of touch?
I have been flying RC since I was 14 - I have a lot of experience of the V2+ and now my P3.
I also happened to run a plastic moulding operation and am a pretty experienced engineer so NO!!!
I was trying to illustrate that if a plastic part is designed and manufactured correctly then there should be no problems even if there are high frequency vibrations.
I also don't believe in making nasty remarks against individuals on forums..............

 

[III% Streve]

Nasty? I didnt realize showing appreciation for a laugh was somehow an insult where you come from.

 

[Wibble]

Nasty? I didnt realize showing appreciation for a laugh was somehow an insult where you come from.

Ahh I thought you were suggesting I was a ranting drunk............
Hic

 

[envisionabove]

First: I would like to step in and say everyone is showing why this forum is Number One for the DJI Phantom line. ( I hope they take Notice of the Professionalism this board has giving since it's Inception. ) Plus the Humor .

eBird welcome aboard! You are a new member and I must say your going to bring a hefty wealth of polite and knowledgeable welcome support here.

This is the first report of the new shell failing. That I have read, mind you I fly more than read after the DJI Go app release. Android
Variables aside not good news.
Not good news but rare...
We have a large amount of talented members available and being this is a rare report to the OP's post we will have to level quite a few questions.

For Visitors reading this thread and thinking of buying a DJI Phantom this is not a major issue and for now is a one off occurrence.

Thanks again keep up the good work and Fly!

 

[Dounin Front]

First: I would like to step in and say everyone is showing why this forum is Number One for the DJI Phantom line. ( I hope they take Notice of the Professionalism this board has giving since it's Inception. ) Plus the Humor .

eBird welcome aboard! You are a new member and I must say your going to bring a hefty wealth of polite and knowledgeable welcome support here.

This is the first report of the new shell failing. That I have read, mind you I fly more than read after the DJI Go app release. Android
Variables aside not good news.
Not good news but rare...
We have a large amount of talented members available and being this is a rare report to the OP's post we will have to level quite a few questions.

For Visitors reading this thread and thinking of buying a DJI Phantom this is not a major issue and for now is a one off occurrence.

Thanks again keep up the good work and Fly!

Hello Tim--you must be DjiTim from the Dji Forum. I am very glad to see you are monitoring this forum as well. It's good that Dji is really interested in what customers are finding and saying about their products. I for one think Dji is doing a great job of listening and solving people's problems, while continuing to enhance the functionality of the P3 products.
So, how about a collision avoidance feature accessory for the P3? All the cars have them these days ;-)

 

[Wibble]

Collision avoidance would be great - would it pick up something like a telephone wire? Doubt it. Would be good for indoor work though.