Laser not cutting all the way through

Snapmaker 2.0 (3-in-1)
3

I have also done some laser cutting tests. Sadly, the provided 1.6W laser is quite week and the smallest possible focus size quite large with a very short focus length. Therefore, the wood cutting experience I had so far was rather bad. Nevertheless, I did cut 3mm birch plywood (made of 3 layer of wood) in 35…40 passes at 120mm/min. Remember that the type of wood is quite critical. Harder wood tends to cut harder. You can take a look at the Janka scale to find out how hard your type of wood is.