Four Square Cube
The dictionary defines a cube as: A symmetrical three-dimensional shape, either solid or hollow, contained by six equal squares.
Here's how to make a symmetrical 3D shape contained by four equal squares. That is: a 4 square cube.
Side views of the cube show them to be square.
There's a Twist
While the cube is made of only 4 squares there's is a twist, the sides aren't flat..
Making a Frame
The cube is made by joining together 4 saddle surfaces. These were moulded over a frame.
The frame is made using 4 lengths of dowel joined together to make a 3D - 'W' as shown in the photo. String is strung parallel to two of the dowel lengths to form a saddle shape.
Making the Mold
Masking tape is placed across the strings to complete the surface of the mould. Then cling film is placed over the masking tape and wetted plaster cloth layered on it. After the plaster has set it is removed from the model.
Make four saddle surfaces in the same way.
Join Four Together
After four saddle surfaces have been made with equal sides, join them together and secure with plaster cloth.
Paint on Some Strips
Paint on some strips to help make the curved surface look flattish when viewed from the sides. These lines are made a little fatter the further away they are from the viewing point on the surface. This is done to counter perspective.