Mold steel thickness: 20mm, thickness at hole: 2mm, small hole diameter: 0.15mm
Ensure the drill bits are less prone to breakage by focusing on the following aspects:
(1) When in use, remove the drill bit from the packaging box and immediately insert it into the spring chuck of the main spindle or into the automatic bit changer. After use, return it to the packaging box immediately.

(2) Measure the drill bit diameter using a tool microscope or other non-contact measuring instruments to prevent the cutting edge from being damaged upon contact with a mechanical measuring device.

(3) Some CNC drilling machines utilize position rings, while others do not. If position rings are used, the depth of installation must be precisely aligned. If position rings are not used, the extension of the drill bit onto the spindle should be adjusted uniformly, especially for multi-spindle drilling machines where consistency is crucial. Each spindle's drilling depth must be uniform. Inconsistencies could lead to drill bits penetrating the table or failing to drill through the PCB, resulting in scrapping.

(4) Regularly inspect the concentricity of the main shaft and collet chuck, as well as the clamping force of the collet chuck. Poor concentricity can lead to broken drills in small diameters and larger hole sizes. Insufficient clamping force can cause the actual speed to mismatch the set speed, resulting in slippage between the collet and the drill bit.

(5) Regularly inspect the main spindle pressure foot. The contact surface must be level and perpendicular to the main spindle without any movement to prevent broken drills and misaligned holes during drilling.

(6) The drilling machine should have excellent dust extraction, as the suction can lower the drill bit temperature and simultaneously remove dust to reduce friction-generated heat.

(7) Re-grinding drills at the proper time can increase the usage and re-grinding次数 of the drills, extending their lifespan and reducing production costs. Typically, a tool microscope is used to measure, ensuring that the wear depth within the full length of the two main cutting edges is less than 0.2mm. During re-grinding, 0.25mm should be removed. Standard fixed-handle drills can be re-grinded up to 3 times, while undercuts can be re-grinded 2 times. Over-grinding will decrease drilling quality and precision, potentially leading to scrapped printed circuit boards. Over-grinding can have an adverse effect.

(8) Pay attention to the adjustment of machine tool processing parameters