The layered structure of plywood, combines different wood veneers. How the plywood is "glued" together directly affects its quality.
FK plywood is most suitable for laser cutting, because urea resin is used as a gluing material. When working with such plywood the cutting performance is much higher than when working with moisture-resistant materials: PSF, glued with phenolic resin and FB, impregnated with bakelite varnish.
Plywood varies by grade. For laser cutting, take the 1st and 2nd grades, as there are almost no knotty veneer sheets (the laser beam is very bad at cutting knotty areas). Grade 3 and 4 are used as invisible elements, where the quality of the cutting edge is not important. But in this case you have to cut with a higher power laser beam.
❗️For the engraving to be clean, with a minimum of fouling, it is necessary to lower the air pressure. This is to prevent the fouling from being carried away by the strong air.
