Hi Steve,
I am relieved you are not flying that heap of trashcan material, for if in developing that size of crack what else nearer to the Donk has also been subject to similar oscillations but possibly accelerated due to the length of the arm inducing neg/pos stress
Almost suicidal maintenance...or should I say "Lack of knowledge on spinning machinery will create cracks" that denotes failure, that denotes death if flown.
CE should be the one to test fly.....
Peter R-B