I just came up with the idea of creating a simple shelf for figurines and small items.
While designing my part I added more and more parametric stuff and in the end it is a shelf with hidden dowel connectors. But I did not stop there and made the number of polygons parametric.
So you want a triangle shaped construct as a shelf. Just set the faces to 3. Hexagon? Use 6.
I already printed a miniature of a triangle shelf to test the interlocking mechanism and as you can see it works like a charm. Since I wanted a test print, I choose a miniature triangle shelf, but even so I printed in ABS, it came out nicely.
As you can see the default sizes of the interlocking mechanism are not scaled. However you can change parameters to increase the e.g. screw hole or the interlocking slot, too.
If you want to play with the design here is the FreeCAD source file. I used the RealThunder branch, but I did not do any special operation, so it should be compatible:
PolygonShelf.FCStd (99.2 KB)
Please let me know if you liked it or even made a useful print out of it.