1.The drill bits should be packed in special boxes to avoid vibrations hitting each other.

2.When in use, the drill should be removed from the box and immediately fitted into the collet of the spindle or into the tool magazine of the automatic drill change. Return to the box as soon as you have finished using it.

3.Use a non-contact measuring instrument such as a tool microscope to measure the diameter of the drill, to avoid the cutting edge being touched by contact with a mechanical measuring instrument.

4.Some CNC drilling machines use locating rings, some CNC drilling machines do not use locating rings, such as the use of locating rings, the depth of its installation must be accurate positioning, such as not using locating rings its drill bit mounted on the spindle extension length to adjust the same, multi-spindle drilling machines should pay more attention to this point, to make the drilling depth of each spindle to be consistent. If inconsistent, there is a risk that the drill will reach the table or fail to drill through the circuit board causing scrap.

5.A 40x stereo microscope can be used to check the wear on the cutting edge of the drill in normal times.

6.Always check the concentricity of the spindle and collet and the clamping force of the collet. Poor concentricity will cause broken drills and large hole diameters in small diameters, etc. Poor clamping force can cause the actual speed not to match the set speed and slippage between the collet and the drill.

7.The clamping length of the fixed shank drill in the collet is 4 to 5 times the diameter of the shank in order to clamp it firmly.

8.Always check the spindle presser foot. The contact surface of the presser foot should be horizontal and perpendicular to the spindle so that it does not wobble to prevent broken drills and deviated holes in the drilling.

9.The drilling machine should have a good dust suction effect. The dust suction air can reduce the temperature of the drill bit and at the same time take away the dust to reduce the high temperature generated by friction.

10.The substrate stack including the upper and lower pads should be positioned firmly and leveled in the one-hole, one-slot positioning system on the working table of the drilling machine. The use of adhesive tape is required to prevent the drill bit from drilling on the tape and causing the drill bit to adhere to the chips, resulting in difficult chip removal and broken drills.

11.The drill bits from the ordering manufacturer are randomly checked for 4% compliance when they are inspected at the factory. And 100% of them are inspected with a microscope of 10 to 15 times for chips, abrasions and cracks.

12.Resharpening the drill at the right time can increase the use of the drill and the number of resharpening, prolong the life of the drill and reduce production costs and expenses. Usually measured with a tool microscope, the wear depth should be less than 0.2mm in the whole length of the two main cutting edges, and 0.25mm when resharpening. Ordinary fixed-shank drill bits can be resharpened 3 times, and shovel-shaped bits (undercut) can be resharpened 2 times. Too much resharpening will reduce the quality and accuracy of the drill holes and will result in the scrapping of the finished circuit board. Excessive resharpening 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.In general, the manufacturer provides a list of parameters for the drilling speed and down speed of the drills produced by the factory. These parameters are only for reference, but the actual technician has to come up with the actual speed and down speed of the drill after actual use.