This is a 3D tic-tac-toe board, either for laser cutting or 3D printing.
You need four shelves, four pillars and a base.
I lasercut mine. The default settings are for 3.25mm thickness material for the shelves and pillars, and for two stacked 6mm thick pieces for the base. I used acrylic for everything but the base, and plywood for the base.
For 3D printing, you may want to change the thickness settings a bit: 3.25mm seems a bit thin. But I haven't tried the 3D printed version.
ttt-base.stl | 17.1KB | |
ttt-pillar.stl | 14.3KB | |
ttt-shelf.stl | 261.6KB | |
ttt-standalone.scad | 4.9KB |