Advice for when it arrives water cooling is vital letting the tube get over temp will kill it very quickly, operating at 100% will reduce life of tube so use minimum required to do job, there are suppliers of MDF and PLY for laser cutting that cut much easier and better than standard supplies couple fo examples just first to come up on google below these have been manufactured for laser cutting and some older PLY etc is difficult to cut with laser. Make sure mirrors and lenses are always kept clean and aligned and protect eyes at all times.
https://hobarts.com/sheet-materials/...mdf_124_15_55/
https://www.kitronik.co.uk/materials...xkxRoCq_rw_wcB