The base of the stool is made from 9 mm birch plywood. In this special case I used plywood with light glue. Normally a water resistant glue is dark, but I got this material from a special model at a local wood dealer. The construction in not really complex, but as I draw most of my (technicals) design using SolidEdge 2D it was quite challenging to get everything right in 3D. The design allows effective nesting and the legs are glued together from 3 parts.
I got my hands on some sheets of 10 mm acrylic glass. It's the same material I used for my Bedside-Reading-Lamp "Waveguide" and like with that project I utilized the feature that acrylic glass can be bend if heated. So I cut the squircle shape rounded the edges with a handheld router and a roundover bit and put the result into the oven. Baking the thing for 10 minutes at approx. 170 °C and it can be bend rather effortless. I used oven cloth and a bowl to make the rounded shape.
The seat is screwed onto the base with 30 mm machine screws. I predrilled the acrylic glass and the wooden base and this gives a last remnant of rigidity. A reason for using machine screws over wood screws are the screw heads: it's really hard to find wood screws that work with allen keys.
After mounting the clear acrylic seat the result with actually unwontedly. I thought about applying a matte finish, but as I had not sandblaster settled with painting it. Using a spray paint I painted the underside of the seat, which just looked great.