I agree with cowpen, looks like over tightening to me.
Yes, too much torque will not help, you're right, but I don't think this is the main reason why.
My last 2 p3s have only cracked after the first or in my case, 4th GENTLE flight with mostly hovers.
If the screws were torqued too much, why didn't it show any cracks before first flight?
It cracked AFTER the first or in my case 4th flight, BECAUSE of thrust making the joints weak and then finally cracking (stress crack).
DJI really should be doing something about this instead of ignoring the fact that this IS a BIG problem with phantom range shells. Repairing them is not gonna fix the problem in the long run.
I'll say it again, it's only a matter of time before others see cracks or worse CRASHES due to this.
I know one thing, I'll NEVER buy anything from DJI ever again. I've learned a lot over the last few months...
Thanks to everyone for commenting on this thread - do keep them coming!