It is well known that the diameter of cutting tool should be the same as the diameter of cam follower, otherwise it is impossible to fabricate the precise cam track. However, if the error is permissibly small during the roughing mill-process the use of a smaller cutter is preferred due to the cost. For the case of cylindrical cam with translating follower, the tool offset and the offset error have been studied. Here a plainer methodology to obtain the tool offset and offset error of the smaller cutting tool for a cylindrical cam with translating and oscillating followers is proposed, then the offset error is evaluated accordingly based on the analytical procedures. The evaluation of error is useful to determine the minimum size of cutting tool for finishing milling and grinding process. As a result of the simulations, it becomes clear that one or two rank size down cutter can be used to mill the cam track.