Step 5: Joints and Hydraulic Cylinders
The shoulders simply had a T connector that I could attach to PVC pipe that was sticking out of the shoulders of the arms (free to rotate). The hips had a piece of PVC pipe that could attach to a connector piece on the upper legs (this proved difficult, more on that later). The top piece of the cage and headpiece was attached to the torso with wooden dowels aligned in joint holes. The pincers attached to the forearms with a PVC pipe connector.
Hydraulic cylinders were basically be a piece of wooden dowel covered with aluminum tape (idea credited to flaming_pele!), that could slide in and out of a larger piece of PVC pipe. Making these light enough and aligned well enough to actually "pump" in and out during motion was difficult.