This is a robotic arm made with the 250mL cans and 3D printed joints and base. Each joint can be adjusted in any position wanted; you simply disengage the gears, rotate the arm and engage again. The cans fit perfectly inside each joint and the joints are included with holes to place a screw and not let the aluminum can move freely. Also a metal clip can be placed at the axle of the joints to lock it in place and dont have to worry about it falling apart. As seen in the pictures, the starting position of the arm can be set to any angle desired. 

This basic robotic arm can have many purposes, but the attachment I included in this model is the 'can' holder at the end. This is also a great model to teach kids of how a real robotic arm works in the industry, except they use motors at each joint to control the positions. Unfortunately I dont have access to a 3D printer to be able to print the joints and show the assembled robotic arm;however I would definitely love to have this robotic arm on my desk and attach many other end-effectors for different purposes.