I used oak sheet i got from a big box store, i think i was 10 bucks for a 4 foot by 6 inch peace that is .25 inch thick. This is made with 2 bits, first is a .0625 for all the flat spaces and then a 60* v bit is used to get all the detail and sharp edges. cut depth is .1 deep. after they are cut out i sand down to a 320 grit and airbrush the surface and sand again to get the detail to show. finally i use 3 coats of a furniture grade high gloss clear poly for durability. The back is 1/8 cork from a hobby store i cut slightly smaller and glue on with a spray glue that is moisture resistant.
i have a touch plate that i installed into my machine and i use a excel spread sheet that is set up to generate the codes for doing a true Z zero depending on what bit i am using. If you dont have one yet i highly recommend it. mine cost me about 15 bucks. i can help you all the way for installation and use