https://www.artic.edu/artworks/126431/balance-beam-scale-with-incised-circles-and-strings-attached
Balance-Beam Scale with Incised Circles and Strings Attached | The Art Institute of Chicago
balance beam scale
https://www.instructables.com/Razor-Blade-Equal-Arm-Beam-Balance-Micro-Scale/
Razor Blade Equal-Arm Beam Balance Micro Scale : 10 Steps (with Pictures) - Instructables
Razor Blade Equal-Arm Beam Balance Micro Scale: I made it at Techshop. http://www.techshop.ws/ This is my version of an Equal-Arm Beam Balance Micro Scale. It...