First I tried to make the stacked tans from dismantled cheap plastic snakes.
Here is the set of Tetratan. The set is divided into five subsets:
Property of Pieces
Number of Pieces
Height=3 or Height=4
14+1
Two tans in each layer
15
Rectangular trapezium in bottom layer
10
Three tans in one layer, but no rectangular trapezium
12
Height=1
14
This way it's easier to search for a special piece, when a construction is built.
Unfortunately the triangular faces of the tans aren't perfectly plane.
Therefore a higher construction is determined to crash. Especially the piece with
height=4 is very unstable.
If the height of the figur is smaller than 6 and the higher pieces are squeezed,
stable constructions are possible.