Inspect your P3 before flight!

[skeptic49]

If, as has been suggested, the issue is either too much torque on the screws, or weakness of the plastic, I am hoping that the installation of these thick prop guard mounts combined with hand tightening the screws will prevent shell cracks. My P3S is new with just a little over an hour of flying time and seven flights, and it does not have any of the dreaded stress cracks. The prop guard mounts are contoured to fit the curved shell and hopefully should serve to strengthen the motor mount area and spread the stress load out a bit.

 

[Dronut2]

Definitely wasn't the heat. Last flight, the temp was 70F and cloudy. I'm just as surprised as you are, or more so even... I wouldn't come online with pictures to lie to a bunch of people I've never met lol.

It's still under the 2 year warranty I purchased through BH but it sure does suck to have to send it out for replacement or repair.

There is a temperature gradient from ground level on up. Maybe you have thermal shocked the unit. Metal motors contact at a lower ratevthan the pastic. Metal has a CTE of 12 in/in per degrees C. Plastics are probably 30 or greater. The plastic will contract faster than the metal in cold. If the plastic is not flexible/brittle it will crack. But what do I know? I only design parts for spacecraft, rockets, anirplanes...

 

[Dronut2]

There is a temperature gradient from ground level on up. Maybe you have thermal shocked the unit. Metal motors contract at a lower rate than the plastic. Metal has a CTE of 12 in/in per degrees C. Plastics are probably 30 or greater. The plastic will contract faster than the metal in cold. If the plastic is not flexible/brittle it will crack. But what do I know? I only design parts for spacecraft, rockets, anirplanes...

 

[Insanehobbies]

I discovered this crack on my phantom yesterday and was wondering if it would be safe to fly a couple more flights with it as I am going on vacation. Could somebody please help with this question.

 

[Insanehobbies]

Here is another pic.

 

[FLYBOYJ]

Here is another pic.

Personally I would fly it but I would avoid rapid accelerations/ decelerations and sudden braking. I would also avoid high speeds. Inspect after each flight.

 

[FLYBOYJ]

This is how I'm dealing with stress cracks on one of my birds.

Stress cracks under motor

 

[Insanehobbies]

Thank you for the reply. I just ordered a new shell and the motor reinforcements. Also ordered the plast aid and should have that tomorrow. Just a quick question how long with the repair take me if I replace the shell. Or how long if I just did the repair and I am a pretty hands-on person do you think I should attempt this? Thanks for your help

 

[macoman]

Thank you for the reply. I just ordered a new shell and the motor reinforcements. Also ordered the plast aid and should have that tomorrow. Just a quick question how long with the repair take me if I replace the shell. Or how long if I just did the repair and I am a pretty hands-on person do you think I should attempt this? Thanks for your help

If you are not good with electronic circuits, I will rather send it to a repair center. I prefer professional results.

 

[HWCM]

If, as has been suggested, the issue is either too much torque on the screws, or weakness of the plastic, I am hoping that the installation of these thick prop guard mounts combined with hand tightening the screws will prevent shell cracks. My P3S is new with just a little over an hour of flying time and seven flights, and it does not have any of the dreaded stress cracks. The prop guard mounts are contoured to fit the curved shell and hopefully should serve to strengthen the motor mount area and spread the stress load out a bit.


View attachment 83403 View attachment 83404 View attachment 83405

Those will add stress and probably cause the cracking to be worse.

 

[HWCM]

If you have fine hairlines, I will try to see how long and deep their are. If they are not too long, I will put some kind of glue for plastic so it does not spread. But if their are long and deep, a shell replacement will be necessary.

Sure, put tape and glue all over a $1000 piece of equipment. That is awesome...

 

[HWCM]

Tell that to all the people whose dashes look like spiderwebs down here. Armor all is just the most well known brand, but it does work. And yes, if you over-do it it comes out like the old Soul Glo skit.

It is just watered down silicone. Modern dashes do not really crack anymore. Armour all or not. The stuff just attracts dust.

 

[HWCM]

Sorry I should've been clearer. There's no issue with using the blue loctite on the motor bolts as it's metal-to-metal.
The metal-to-plastic screws don't need any locking compound.

EDIT - I've just been looking at the type I've been using and it's 425, which is safe to use in plastic.

I understand. It is the vapors that dissolve the plastic. It doesn't have to be contact.

 

[HWCM]

+1 on this. Now granted, I used to build race cars for a living, and I am mechanically gifted. However, anyone with enough patience and the right set of little drivers from walmart can handle it. Like I said, I just re-shelled my P3P. The shell is authentic and cost me 60 bucks. I swapped it over in about 3 hours taking my time. Now my P3P looks absolutely brand new and Im back in the air. It feels good to fix it too!


Oh and for what its worth, it had three massive-*** cracks in the right rear motor arm (all from just stress) and a chunk missing between said cracks, and it still flew flawless. Hell, the motor may have only been secured in 3 places at that point, who knows?

Well, this could happen...
Catastrophic design flaw of Phantom 3

 

[Wiegand]

If, as has been suggested, the issue is either too much torque on the screws, or weakness of the plastic, I am hoping that the installation of these thick prop guard mounts combined with hand tightening the screws will prevent shell cracks. My P3S is new with just a little over an hour of flying time and seven flights, and it does not have any of the dreaded stress cracks. The prop guard mounts are contoured to fit the curved shell and hopefully should serve to strengthen the motor mount area and spread the stress load out a bit.


View attachment 83403 View attachment 83404 View attachment 83405

Two important things, do not add too much weight and,I forgot, the propellers must be carefully balanced !

 

[HWCM]

Two important things, do not add too much weight and,I forgot, the propellers must be carefully balanced !

Neither of those have anything to do with shell cracking.

 

[trigon]

Well I have a P3P since the day they started selling it and I have no problem with any cracks anywhere on it (I crashed it twice and had to change a few parts but still no cracks) so I think its about the way you fly it! When u use it as a toy (racing with drone, full throttle etc) then you have such a problems but I am shooting with it for a quality images and therefore I never put too much on it because every agressive movement is causing my shots to be ugly and shaky etc...

 

[Wiegand]

Neither of those have anything to do with shell cracking.

..interesting consideration...vibrations of not balanced propellers and weight at the edge of the arms have not anything to do with shell cracking....again, everyone can do what he likes.

 

[With The Birds]

Well I have a P3P since the day they started selling it and I have no problem with any cracks anywhere on it (I crashed it twice and had to change a few parts but still no cracks) so I think its about the way you fly it! When u use it as a toy (racing with drone, full throttle etc) then you have such a problems but I am shooting with it for a quality images and therefore I never put too much on it because every agressive movement is causing my shots to be ugly and shaky etc...

Unlikely any in flight manoeuvre might apply more force to the shell than crashing. This is a material composition, manufacture, assembly and or design issue.

 

[Numone]

I understand. It is the vapors that dissolve the plastic. It doesn't have to be contact.

How do you make these statements without the facts, HWCM? As I said, its designed for use with metal and plastic.
https://www.silmid.com/dsweb/Get/Document-219655/LOCTITE 425 - TDS.pdf