During the process of CNC machining plastic parts, it is important to keep the workbench maintain clean. Besides, the hardness of plastic is low, and the surface is easy to be scratched. If the machine is used directly to process plastic parts after the completion of metal parts, the surface of plastic parts will be scratched. Therefore, Bordersun insist that metal parts and plastic parts should be made with specified machine separately.
When process CNC machining plastic parts, it has strict requirement on temperature. When temperature is low, materials are easy to crack or deform. When temperature is high, materials will melt and adhere to the cutter, besides, the surface will form a layer of some white paste. Before manufacturing CNC machining plastic parts, appropriate materials should be well-prepared. According to different materials, hot water soakage will be done to release the internal stress.
Common materials of CNC machining plastic parts include ABS, PC, POM, PP, PMMA, PEEK, PS and thermal-resistant materials, like PPS, PTFE, bakelite, black PC and PA+30%GF. For the parts with complex structure, we will use high-speed numerical controlled machining (4-axis or 5-axis) to help customers quickly verify the accuracy of the material, dimension, color and design of the product.
Generally, the tolerance of CNC machining plastic parts is between±0.1mm. If you require the tolerance less than±0.1mm, all you need to do is sending us the 3D drawing, in the format of PDF, DWG or DXF. Bordersun will provide a full-measurement report to the first ten parts, to ensure the prototypes you received conform with the dimension and precision requirement.
ABS has good properties in terms of machinability, anti-impact strength, and structural stability. After polishing, the surface of ABS is highly smooth, and it can be painted or electroplated with different color. CNC precision machining ABS parts are used widely in automobile, electronics, domestic appliance and the shell of automation equipment. The shell of television is made by flame retardant ABS. Besides, inside the fax, fan, air conditioner and air purifier, there are many ABS parts.
The dimension of PC is stable, and it can keep the rigidity in wide range of temperature. And even in low temperature, PC still has great anti-impact strength. CNC precision machining PC parts are mainly used for the complex parts with curved surface, like impeller, air inducer wheel, spherical surface and propeller.
Filings splash during the cutting of metal. The cutting of CNC precision machining PA parts is different from that of metal. It is like the process of pencil sharpening, with scraps winding around the cutter. During the process, scraps accumulate and temperature rises, and PA scraps will melt and adhere to the cutter. It is difficult to clean. The common solution is slowing down the cutting speed, lifting the cutter intermittently and adding coolant liquid. However, during the processing of PA, the scrap is filiform and tangled, and it cannot be washed away by the coolant liquid. Blower gun is more effective than coolant liquids. And we use high pressure blower gun to blow constantly to prevent the conglutiantion of nylon filament with the cutter.
CNC Precision Machining PMMA Parts performs good in electrical insulation and machinability. The transparency of CNC machining PMMA parts can be 95% after polishing, and PC is incomparable. There are transparent materials among PC too, but the transparency is not as good as PMMA.
PP performs excellent in anti-impact strength, fatigue resistance and machinability. For small batch PP parts, usually we will choose CNC precision machining PP parts.