You might try using a thin cutoff wheel in a die grinder and attaching that to the toolpost to grind a break in the chrome at the limit of your turning. If the shaft was steel you could just go at it with no worries, but when the part is aluminum the chrome isn't bonded well at all. If the part is subjected to any type of cyclic loading it will most likely begin to peel at the edge anyway over time. If the part just sorta lays there, the chrome should hold up fine.