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        1、IQC must carry out spot checking before entering the warehouse to check whether there are scratches on the surface of the copper clad laminate. If so, it should contact the supplier in time and make appropriate treatment according to the actual situation.

　　2、Copper clad sheet is scratched in the course of tapping. The primary reason is that there are hard sharp objects on the table surface of the tapping machine. When tapping, copper clad sheet and sharp objects are scratched to form an exposed base material. Therefore, before tapping, the table surface must be carefully cleaned to ensure that there are no hard sharp objects on the table surface.

　　3、Copper clad plate is scratched by drill bit when drilling. The primary reason is that the main shaft clamp is worn out, or there are sundries in the clamp which are not clean and clean. PCB proofing can not grasp the drill bit firmly, the drill bit is not up to the top, which is slightly longer than the length of the drill bit set, the height raised during drilling is not good, and the drill bit tip scratches copper foil to form an exposed foundation when the machine tool moves. The phenomena of wood.

　　a、The number of times that can be recorded by the grabber or the replacement of the clamp according to the wear degree of the clamp;

　　b、Clean the clamp regularly according to the operating rules to ensure that there are no impurities in the clamp.

　　4、Sheet metal is scratched during transshipment:

　　a、When transferring, the transferring personnel lift too many plates at one time and the weight is too large. When transferring, the plates are not lifted, but dragged along with the trend, forming the corner of the plate and scratching the surface of the plate due to friction between the plate and the surface；

　　b、When the plate is lowered, the surface of the plate is scratched due to the friction between the plate and the plate.

　　5、After sinking copper and plating the whole plate, the stacking plate was scratched due to improper operation：

　　After copper sinking and plating, when the plates are stacked together, the weight is not small. When the plates are laid down, the angle of the plates is downward and there is a gravity acceleration, which constitutes a strong impact force on the plate surface and scratches the exposed base material.

　　6、The production board is scratched when passing the horizontal machine：

　　a、The baffle of the grinder sometimes touches the surface of the baffle. The edge of the baffle is generally uneven and the sharp objects are raised. The surface of the baffle is scratched when passing the baffle；

　　b、Stainless steel transmission shaft, because of damage to a sharp object, scratched copper surface when passing through the plate and exposed the base material.

The article originated from Jiangmen single-sided and double-sided circuit boards. http://www.jzfwq.com/