what does a key do in a tapered shaft
1,442. Dsergison is right that since a Woodruff keyseat is round, alignment is irrelevant for the keyseat in the shaft. IME seats for straight keys in tapered shafts or bores are parallel to the axis, not the surface. tapered keyseat might bind radially before the shaft and bore were in proper contact, and this would negate the reasons for the taper fit. Usually the taper fit between shaft and bore also carries torque well, so key is more for registration than torque, another reason why you want a straight, non-binding key fit.