NC geometric cutting simulators are a widely used software. However, it is difficult to represent the cutting load, tool deflection and tool wear caused by physical phenomena. The purpose of this research is to develop a NC geometric cutting simulation that will be able to easily calculate these phenomena during simulated machining. This paper describes the calculation algorithms of cutting loads, deflections, and wear of tools based on a removal volume, and the implementation of the NC geometrical cutting simulator. The removal volume is an interference area calculated between a workpiece and a swept volume of the tool movement, and the removal volume at each height is calculated at the same time. As a result, it is confirmed that the proposed algorithm is able to estimate the cutting load and the tool wear.