Mod a Neje Laser Engraver - to engrave larger object

i want to laser engrave a chopping board for my friends at City Life Meal, but the machine i have only fit 4cm by 4cm, so i need to mod it so it can laser basically unlimited area, here's how i do it.

video about this machine: https://youtu.be/Kg9wlPY0F2U
post about this machine: https://dali-lomo.blogspot.com/2018/04/100-neje-laser-engraver-dk-bl1500mw.html