To drill a satisfactory hole in any thermoplastic material, the correct type of drill bit must be used; additionally it must be used correctly and be sharpened appropriately. Aline's basic strategy in drilling into any plastic is to use the right bit at a slow speed to minimize heat. Not only are plastics soft enough to be drilled with dull bits, most manufacturers prefer to use dull bits to sharp bits. Sharp drill bits tend to create tiny splits in the plastic when it breaks through the bottom surface.
Before use, many of our bits are slightly blunted. When drilling plastics with conventional, high-speed, blunted twist bits, we utilize slower speeds of 500-1,000 rpm for the best results. With years of experience in plastic injection molding and manufacturing, our machinists know that if the bit creates shaving than they are drilling at the correct speed, but, if it's gumming up, than they know to let it cool down and go even slower. Our knowledge in the industry helps us rise above the competition.
When drilling a hole three times deeper then the diameter of the drill, we use a lubricant or coolant such as water. This helps remove chips, dissipate heat, and improve the finished hole. When drilling plastic we never stop the bit while it's in the hole. Instead, we always back the bit out of hole to prevent melted chips from fusing to the workpiece.
Rough, irregular, or fuzzy holes can cause cracking and breaking well after the piece has been completed. We take pride in providing our customers with custom plastic parts or components that last and, for this reason, utilize different strategies to prevent cracking. Two of these strategies consist of making sure that the holes are in as far from the edge as possible and reducing drilling speeds immediately before the bit exits the workpiece. To avoid clogging the flutes of a twist drill bit, our expert machinists clear away long, spiraling chips produced when drilling plastics.