Turning,milling,drilling are used a lot in plastic fabrication. Typical tool material for CNC turning and milling is high-speed steel (eg.W18Cr4V, W6Mo5CrV2) and tungsten carbide (eg.YG3X and YG6X)

CNC Turning

When turning PVC or acrylic with high-speed steel and tungsten carbide cutters, the max speed can be 600m/min. The max speed for turning HDPE can be 700m/min. Max speed for PS and PTFE can be 70-120m/min. But when turning nylon plastics, high-speed steel cutter is 40-50m/min. Tungsten carbide cutters is 110-130m/min. As nylon has poor heat resistance, over-speed turning will make materials soft and decrease the surface quality of the products.

CNC Milling

The most common milling tool are cylindrical milling cutter and end milling cutter.

The milling cutter for plastics are different from cutters for metals. The characteristics of milling cutters for plastics should be as below.

1.The cutter edge should be rake angle and clearance angle

2.Since the power generated by plastic milling is much smaller than metals, we can choose bigger diameter milling cutter according to the actual situation.

3. When cutting thermoforming plastics, there are lots of fluffy swarf. So we should leave bigger space for swarf.

Drilling

The typical characteristics of plastic drilling are as below.

1. There are smears when drilling.

2. There are burrs when the drilling bit come in and come out from the holes.

3. The holes will become smaller as plastics has high linear expanding coefficient.