Managing surface location error

Machinists and many NC programmers are faced with the problem of tool and workpiece deflection in response to the cutting force, removing lesser material than planned. It is noted that even if tool deflection is proportional to cutting force, generation of the surface is more complicated. One case can be where the radial DOC is small enough that only one tooth is in contact with the workpiece when a tooth is in position. If the radial DOC increases, the condition at the instants in time when the desired surface is generated does not change until the second tooth becomes involved in the cut. The error in surface location undergoes a sudden step change when the second tooth begins to cut. For slow-speed milling, applying a tool with six straight teeth, where the radial DOC is gradually increasing, the surface location error does not gradually increase. If tool deflection changes with time, the surface location error changes from the bottom to the top of a wall created by the endmill.