How accurate and how fast do you want to be cutting? The design links to a gantry router that is acrylic and MDF. Not the greatest materials to work with. You might want to look at some of the designs here. There are a few designs that use ply laminate with epoxy that have a reasonable life span but it really depends on how long you plan on using your machine and what accuracy you are looking for and longevity. Acrylic doesn't like stress and MDF like's water a lot.

Design depends on what you are looking for and what you want out of it. Gladly help as I can.

Michael
MM0MSU