12.5 cm x 11.5 cm x 11 cm / 4.9 in x 4.5 in x 4.3 in
Screwballs is an easy assembly puzzle, first designed and prototyped in May 2009. The puzzle has six identical rods with right and left-handed threads at the end, and four different balls, each with three threaded holes. The object of the puzzle is to assemble a tetrahedron. Because of the threading, the puzzle is assembled as an implosion, i.e. turning all the rods simultaneously and puzzling the balls together. "Screwball" is also a baseball pitch, as well as the name of several other things, now including a puzzle design :-).
CAUTION: Please turn the rods carefully while maintaining symmetry. If you screw one rod too far with too much force, you may break something.
The set of ten pieces took nearly 7 hours to 3D print on a Dutchy 3D printer. 100 gram (34 meter) of 1.75-mm filament was used. The puzzle itself weights 63 gram, as 37 gram of material was used for raft supports for the balls and stands for the rods that were printed upright. The filament is based on transparent PLA plastic that is infiltrated with 20% wood fibres, giving its wooden look-and-feel (and smell!). The five types of wood used are birch, mahogany, oak, green and black wood.
Oskar van Deventer has created many different puzzles including his brand of Oskar Puzzles which are mechanical puzzles and objects that can only exist thanks to 3D printing technology. Since 1978, he has been creating hundreds of mechanical puzzles, making him one of the world's most prolific designers. Several of his innovative designs are commercially available.