Wood laser parameter

Unlike acrylic, wood is not a very uniform material. Even when we buy wood from the same manufacturer, every batch may need different power/speed to cut through. MDF has different densities, the dense board is hard to cut. Different types of glue are used in plywood, some are hard for laser cutting. Humidity also affects laser cutting of wood. Good air flow is required for high speed cutting and blowing away smoke. If cutting speed is too low, the cut edge will get burned heavily. Multiple passes at high speed or flipping the part to cut from the other side may be needed to avoid heavy burn.

For engraving, the types of wood that burn easily usually will turn dark. The surface layer is better to be thick when engraving deeply, otherwise the rough under layer will be exposed. Marking detail pictures needs 150~250mm/s speed. Doing vector can be around 550mm/s.
For thickness above 6mm, it is better to use a lens with focal length greater than 2" to cut. For a 2" lens, here are a few cutting speeds(mm/s) for reference: