Here is a parametric triangular box and lid decorated with triangles. A second lid is decorated with squares. OpenSCAD code is included.
square_lid_87.stl | 466.3KB | |
tri.scad | 10.3KB | |
tri_box_80_50.stl | 374.4KB | |
tri_box_random.stl | 507.7KB | |
tri_lid_87.stl | 117.4KB | |
tri_lid_random.stl | 110.3KB |