Cracks caused by flying style?

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I'm a newbie to this sport/addiction. Been lurking threads trying to immerse self with common issues and solutions offered by the many posters. I have gained a wealth of knowledge from the site and others errors, with MUCH more to learn. That said, these crack issues, is it possible it's caused by flying style i.e. P mode vs S mode or Atti mode? Is it safer to fly in "P" mode over the other 2 modes to help prevent cracks? Or does one think being aggressive in takeoffs and flying in general are bigger issues in the cracking? I know its totally possible it's a complete design flaw also but, that would make all crack I believe.
 
While I'm sure some user actions have caused cracks, there seems to be too many people who fly gently with the problem for it to all be user driven.
 
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Crashing should cause cracks..... anything less than that should not be a problem.
If there's a defect, there's a defect.
I don't recall ever seeing a warning label that says, "Caution, flying in S or A mode can damage aircraft. Proceed at your own risk".
 
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I'm a newbie to this sport/addiction. Been lurking threads trying to immerse self with common issues and solutions offered by the many posters. I have gained a wealth of knowledge from the site and others errors, with MUCH more to learn. That said, these crack issues, is it possible it's caused by flying style i.e. P mode vs S mode or Atti mode? Is it safer to fly in "P" mode over the other 2 modes to help prevent cracks? Or does one think being aggressive in takeoffs and flying in general are bigger issues in the cracking? I know its totally possible it's a complete design flaw also but, that would make all crack I believe.
It's a manufacturing flaw and has nothing to do with how you fly.
If (like most owners) you have a good shell, it won't crack at all.
 
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You can't fly beyond the 'system's' programmed limits.
It's common for R/C models operate beyond scale stresses. This is obscured with Phantoms since there is no full-scale equivalent.
Consider 1/10 scale monster trucks capable of 20+ MPH... Ever seen a f/s one doing 200+ MPH?
 
I've wondered as even in the DJI Shell Replacement Kit (~$65 online) that the motor screws provided appear to have some sort of blue Loctite painted onto them. Loctite doesn't play nice with thermoplastics and often hardens them and can crack plastic (Motorcycle 3rd party windshield people found that out.). Loctite makes a screw lock for plastic but it's maybe three times the price of the store brands and most likely DJI uses the cheaper stuff which might be part of this snafu. Could be the Loctite itself too being larger in diameter on the screw stressing the plastic (Unlikely since it should only meet with the motor shell), or the non-compatibility of the screw-lock chemicals and plastics, or ill-fitting bosses between the upper and lover shell where the screws pass through, or over-tightened in general from the factory.

There's some good online Youtube videos of DIY shell replacements, but the motor wiring seems to be a touchy part that leads to the dreaded "ESC Errors" if not done right and a resistance mismatch occurs in the splicing. I don't know if it would be better to solder the motor wires directly to the module itself and avoid the splicing part. Maybe some silver-bearing solder. The motor wires seem to be some coated covering even over the metal wire itself once stripped of the plastic cover and not favorable to soldering well unless scrapped and cleaned (i.e. Wire resistance imbalance = ESC error?).

Once mine gets to the point where the local plastics shop says their Weld-On (CA glue) might not fill the gap or bond well, I may try the DIY shell thing rather than send it in and get back some high-hour refurb model. I'm not crazy about their refurb/service program overall and they may sell your better low-hour model as a "Factory reconditioned" model later and give you someone elses 300 hour model back with scratches and the need to maybe re-file the serial with the FAA if commercially registered, or fight with them to get an Inspire 2 Cinema pre-installed license number back if that model is sent in. Then dealing with the updates and learning how to fly the refurb model as these things seem to have different flight and link-up personalities having had three P4's.

Fwiw...
 
Changing the shell out is not that hard it just takes some time. And one thing, DO NOT CUT THE MOTOR WIRES!! Unsolder the wires at the board or you will be sorry. If you just need the bottom half changed you don't even have to undo the motor wires anyway.
 
I've wondered as even in the DJI Shell Replacement Kit (~$65 online) that the motor screws provided appear to have some sort of blue Loctite painted onto them. Loctite doesn't play nice with thermoplastics and often hardens them and can crack plastic (Motorcycle 3rd party windshield people found that out.). Loctite makes a screw lock for plastic but it's maybe three times the price of the store brands and most likely DJI uses the cheaper stuff which might be part of this snafu. Could be the Loctite itself too being larger in diameter on the screw stressing the plastic (Unlikely since it should only meet with the motor shell), or the non-compatibility of the screw-lock chemicals and plastics, or ill-fitting bosses between the upper and lover shell where the screws pass through, or over-tightened in general from the factory.
The trouble with all the theories is that only a tiny percentage of Phantoms ever develop cracking.
If the theories were correct, almost all would crack but they don't.
 
They all will in time. Doesn't matter to me either way now because I bought my first one and my last one at the same time.
 
Doubtful. If it contains a solvent that reacts with the plastic it will make it (more) brittle.
 
Drill a very small hole at the end of the crack. It's working for me so far.

20170517_193914.jpg
 
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I wonder how many of these cracks are due to the way people are transporting the p4

I see lots of people using soft backpacks where lots of stress is placed on the arms when the bag is carried/thrown around. The stress that can be applied when being carried in a soft backpack would be way more than what stress can be induced went flying
 
I think if your craft is more prone to cracking your flying style will make a difference. I have something like 250 hours and 845 miles on my P4 and I have no cracks on the arms and I fly in s mode all the time, I have a small crack on the lower left side of the battery compartment (glued it), an area that is not subject to any substantial loads, my landings are very soft and I store my craft in a hard case. Some shells have weaker areas than others, considering the loads I put my bird thru at times this machine is pretty amazing.
 

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