The Basic Use Of Common Sense Of Drill

1. The drill bit should be packed in a special packaging box to avoid vibration and collision.

2. When in use, take out the drill bit from the packing box and install it into the spring chuck of the spindle or the tool magazine for automatic drill bit replacement. Put it back in the box immediately after use.

3. To measure the diameter of the drill bit, use a non-contact measuring instrument such as a tool microscope to prevent the cutting edge from contacting with the mechanical measuring instrument and being bumped.

4. Some CNC drilling machines use positioning rings. Some CNC drilling machines do not use positioning rings. If positioning rings are used, the depth positioning during installation must be accurate. If positioning rings are not used, the elongation of the drill bit on the spindle must be adjusted. Consistent, multi-spindle drilling machine should pay more attention to this point, so that the drilling depth of each spindle should be the same. If it is inconsistent, it may cause the drill bit to drill to the table or fail to drill through the circuit board, resulting in scrap.

5. At ordinary times, a 40x stereo microscope can be used to check the wear of the cutting edge of the drill.

6. Frequently check the concentricity of the spindle and the collet chuck and the clamping force of the collet. Poor concentricity will cause small-diameter drills to break and large apertures. If the clamping force is not good, the actual speed will be different from the actual speed. The set speed does not match, slipping between the chuck and the drill.

7. The clamping length of the fixed shank drill bit on the spring chuck is 4 to 5 times the diameter of the drill shank to be clamped firmly.

8. Always check the spindle presser foot. The contact surface of the presser foot should be horizontal and vertical to the spindle without shaking to prevent broken drills and offset holes in the drilling.

9. The dust suction effect of the drill press is better. The dust suction air can reduce the temperature of the drill bit. The colleagues take away the dust to reduce the high temperature caused by friction.

10. The substrate stack, including the upper and lower pads, should be firmly positioned and laid flat in a hole-to-slot positioning system on the workbench of the drilling machine. The use of adhesive tape should prevent the drill bit from drilling on the tape to make the drill bit adhere to the chips, causing difficulty in chip removal and broken drills.

11. When ordering the manufacturer’s drill bit, 4% of the drill bit shall be sampled to check whether it meets the requirements when entering the factory for inspection. And 100% of the nicks, scratches and cracks are inspected with a microscope of 10 to 15 times.

12. Re-grinding the drill in time can increase the use and regrind times of the drill, extend the life of the drill, and reduce the production cost and expense. Usually measured with a tool microscope, the wear depth should be less than 0.2mm within the full length of the two main cutting edges. When regrinding, 0.25mm should be removed. Ordinary fixed shank drills can be reground 3 times, and undercut drills can be reground 2 times. Too much grind will reduce the quality and accuracy of the drilling, which will cause the finished circuit board to be scrapped. Excessive grinding effect is counterproductive.

13. When due to wear and its wear diameter is reduced by 2% compared with the original, the drill bit is scrapped.

14. Drill bit parameter setting. Under normal circumstances, the manufacturer provides a parameter table of the drilling speed and lower speed of the drill bit produced by the factory. This parameter is only for reference. In the actual situation, the speed and down speed parameters of the drill bit are usually different from the reference parameters, but the difference is not too much.