1. There is at least one very small mill/table unit built - as ger21 recalls - I seem to remember it as being not made of acrylic - but cutting board stock. A bit thicker, more rigid, and CHEAP as chips!
2. Also, there is a real sweat acrylic Foam Cutter a French fellow built. So tolerances are not a real problem - nor heat and humidity (room fluctuations).
3. The problem will be getting the framework rigid enough. Years back I built a 2x4 water-table flow bench (like a wind tunnel - but water and near 2D only). The challenge was getting and keeping the table FLAT. I bet the same would apply to the gantry. A lot of engineering (pieces/parts/glue) to get the beam stable and support your spindle.
4. I used Starboard - a plastic like material for the cars on X andY Axis, and most of the Z Axis on my SYSTEM2 - see members gallery. Easy to work with and plenty rigid. Drilled and Tapped well and has held its shape-- no glue required.
Gotta say - it would be very Dramatic looking!
:cheers: Jim
Experience is the BEST Teacher. Is that why it usually arrives in a shower of sparks, flash of light, loud bang, a cloud of smoke, AND -- a BILL to pay? You usually get it -- just after you need it.