1) The diameter of the drill should not exceed the allowable value of the drill.
2) The drill bit must be clamped with a key, and it is not allowed to hit the drill chuck with other tools.
3) When drilling, the force should not be too strong to prevent the motor from overloading. If the speed is found to decrease, immediately turn off the power check.
4) The sporadic workpiece must be firmly attached to the fixture.
5) No gloves are allowed.