1. Broken drill nozzle

　　The reasons are: excessive deflection of the main shaft; improper operation of the CNC drilling machine when drilling; improper selection of drill nozzles; insufficient rotation speed of the drill bit, too high feed rate; too many layers of laminated plates; between plates or cover plates

　　There are sundries underneath; the depth of the main shaft is too deep when drilling, causing the drill nozzle to have poor chip removal and hang; the drill nozzle is ground too many times or used for a long time; the cover plate is scratched and wrinkled, and the backing plate is not flat; tape when fixing the substrate The sticking is too wide or the aluminum sheet of the cover plate and the plate are too small; the feed speed is too fast to cause extrusion; improper operation when filling the hole; serious dust blocking under the aluminum plate of the cover plate; welding the center of the drill tip and the drill shank There is a deviation in the center.

　　Solution:

　　(1) Inform the mechanic to overhaul the spindle, or replace the spindle.

　　(2) Check the geometry and wear of the drill bit and select a drill bit with a suitable length of chip removal groove.

　　(3) Select the appropriate feed amount and reduce the feed rate.

　　(4) Reduce to an appropriate number of layers.

　　(5) Clean the board surface and the sundries under the cover when the board is on, and keep the board surface clean.

　　(6) Inform the machine repairer to adjust the drilling depth of the spindle to maintain a good drilling depth. (The depth of normal drilling should be controlled at 0.6mm.)

　　(7) Control the number of grindings (perform in accordance with the operation instructions) or strictly follow the parameter settings in the parameter table.

　　(8) Choose covers and pads with suitable surface hardness and flatness.

　　(9) Carefully check the fixed state and width of the adhesive tape, replace the aluminum sheet of the cover plate, and check the size of the plate.

　　(10) Appropriately reduce the feed rate.

　　(11) Pay attention to the correct hole filling position during operation.

　　(12) Replace the drill bit of the same center.

　　2. Hole damage

　　The reasons are: take the drill bit after the drill bit is broken; there is no aluminum sheet or a reverse plate when drilling; the parameters are wrong; the drill bit is elongated; the effective length of the drill bit cannot meet the needs of the thickness of the drilling plate; hand drilling; plate Special, caused by the front.

　　Solution:

　　(1) According to the previous question 1, investigate the cause of the broken knife and make the correct treatment.

　　(2) Both the aluminum sheet and the bottom plate play the role of protecting the aperture ring. They must be used during production. The usable and unusable plates are separated and placed in the same direction. Check again before the plate is installed.

　　(3) Before drilling, it is necessary to check whether the drilling depth is in compliance and whether the parameters of each drill nozzle are set correctly.

　　(4) The drilling rig picks up the drill bit, checks whether the position where the drill bit is clamped is correct, and then starts the machine. The drill bit should not exceed the presser foot when starting up.

　　(5) At the drill tip. Visually inspect the effective length of the drill bit before going on the machine, and measure and check the number of stacks of available production boards.

　　(6) Manual drilling and cutting accuracy, speed, etc. cannot meet the requirements, and manual drilling is prohibited.

　　(7) When setting parameters for drilling a special plate, select the parameters appropriately according to the quality, and the feed should not be too fast.

　　3. Hole offset, shift, misalignment

　　The reasons are: the drill bit is offset during the drilling process; the material of the cover plate is not properly selected, and the soft and hard are uncomfortable; the expansion and contraction of the substrate causes the hole position deviation; the matching positioning used

　　Improper use of tools; improper setting of the presser foot during drilling, hitting the pins to cause the production board to move; resonance during the operation of the drill bit; unclean or damaged spring chucks; deviation of the production board, panel hole position or the entire stack position; The drill bit slides when it is in contact with the cover plate; the surface of the aluminum sheet of the cover plate is scratched or creased, and there is a deviation when guiding the drill bit to drill down; there is no dowel; the origin is different; the adhesive tape is not firmly attached; the X, There is a movement deviation in the Y axis

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