Quadror blocks were conceived as a folding support structure. They are composed by 4 L-shaped identical parts that are glued/bolted two by two. This model will print this 4 parts together already assembled. Unfolded quadrors may be placed side by side and stacked to form a wall or a pillar.

References:
Quadror site: http://www.quadror.com
Sketchup model: https://3dwarehouse.sketchup.com/model.html?id=91b5b70ad95fd58b3e232b593c642ba9
Quadror sawhorse model: http://www.thingiverse.com/thing:921314

This model was meant to be printed with a 0.2 layer. I used 2 shells and 20% infill, without any support.

After printing, carefully separate the two parts with a utility knife.