I am engraving/cutting some 3mm red transparent acrylic sheet with paper backing on both sides.
I am using 40% power and 100% speed (default) initially to engrave down about 2mm. This takes about 7 passes at these settings.
The surface of the acrylic after several passes starts to have regular waviness instead of a smooth surface.
I assume this must have something to do with PWM of the laser power?
What is the best way to eliminate the waviness?
Here is an example photo to show the waviness:
![Image](https://www.socialentropy.com/engine/images/wavy_engrave.png)