Ok I have a hex collet block and can see cutting the 6 grooves but how do you accurately re-index the part so you can cut the parallel sides?A hex collet block will work for that.
Ok I think see it... cut the grooves on the top of the shaft then cut the parallel sides with the end of the endmill on the spline sticking out at 90 degrees, then there is no re-indexing needed. Am I seeing that right?