1)Ø19.4 ± 0.1  hole measures Ø20.4mm x 1.5 deep at one position bubbling no 81 at location G21
2)While in machining end mill edge broken.
3) Ø8 x OAL 105 mm end mill with overhang of 65mm.
4)Aluminum scrap got struck in end mill.
5)In sufficient coolant flow to end mill during operation.