Orderly Tangles

And Hart provided a host of way markers throughout.

So this was the first orderly tangle construction I made during the covid lockdown. It's the Four Triangle Polylink. (Actually, this is one of two types of four triangle polylink - the better known one.) As this polylink is thought of as being derived from the tetrahedron, that Platonic solid is considered the structure’s “parental polyhedron.”

The orderly tangle called the Four Triangle Polylink, in its pure form, is made up of interlinking hollow polygons whose central open space is a triangle exactly half the height of the whole shape. The formulation of this polylink is usually explained as the rotation of each face of a tetrahedron by 30 degrees and then the "translation" of each one into the centre of the space that would have been occupied by the polyhedron.