Hard plastics can use twist drills, and soft plastics have special drills. When processing plastic parts, the smaller the helix angle of the drill bit, the less likely it is to cause chips, and the more likely it is to be stuck or burned. Therefore, the helix angle of twist drill for drilling plastics can be larger, but not too large, so as to avoid the drill bit from breaking due to insufficient strength.

Due to the large plasticity and thermal expansion coefficient of plastics, the pore size will be reduced due to elastic recovery and thermal expansion and contraction after processing, so a point slightly larger than the nominal diameter (generally 0.05 ~ 0.25mm) should be selected.