2. Engraving depth is not enough or engraving cannot work?

Reason 1: The focal length is incorrect.

Solution: Re-adjusted.

Reason 2: The laser intensity is not adjusted to the maximum.

Solution: Adjust power to moderate.

Reason 3: Water temperature is too high.

Solution: Replace the circulating water.

Reason 4: Laser tube decay.

Solution: Replace the laser tube.

Reason 5: Optical path deflection.

Workaround: Correct it.

Reason 6: The lens are dirty.

Solution: Clean the lens.