Dropped off my mock-ups and got 'schooled' on what I can expect the waterjet to do with my epoxy/granite. I didn't hear any concerns. As far as I can tell this part of the project is stable. Time is an issue tho'. These guys work hard to pay for the waterjet and the shop is busy. They were cutting a huge sheet of stainless when I brought in my stinky little posterboard pieces. My project felt insignificant by comparison but I picked up points by having pieces "to scale" and a CAD drawing with millimeter dimensions.
I'm using a remnant piece of e/g -- 24" x 30" x 20cm for this first build. The beige color is all wrong but I don't care. I need to learn as much as I can about working with and cutting this kind of material.
Slabs of commercial e/g generally come in two thicknesses -- 20cm and 30cm. The 30cm slabs are normally used for kitchen countertops and vanities and seem to be preferred by architects. A bull-nosed 30cm piece looks like real business. And is.
The 20cm slabs are nicer in my opinion but harder to come by. For our purposes here, 20cm is the way to go and plenty strong.
This will be a heavy, but *very stable* machine.
I've also done some checking and found a manufacturer of 10cm slabs. I'm tempted -- but sticking to my plan. I'll wait and use 10cm in a future build.