The types of CNC machining plastic prototype are various, and different materials need different manufacturing craft. ABS is the most common material for prototype, while PC and PMMA are often used for transparent prototype, like the lens of apparatus, mobile, and glasses. During the manufacturing, it is very important to pay attention to distinct details. Many small workshops chase for the speed and ignore the details, resulting the fall apart of prototype in halfway. It not only results extra cost, but also time-wasting.