I am crazy inspired to attempt a 3d printer!! I have a one time pass to access several commercial copiers that have been retired and are going to be recycled. What specific parts should I salvage for use in building my own 3d printer? I assume they have stepper motors in the scanner section and round track bars and belts and gears. I would also guess they have stop sensors and possibly some circuit boards that would be of use? Any suggestions on what I should grab while I have the opportunity would be appreciated! I'd rather end up with unused parts than wish I would have grabbed something else. Thanks in advance!