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Need to do some heavy lifting of the physical kind, but only have some wimpy servo motors on hand? Why not follow Antonb’s directions to Hack your Servo, and turn it into a powerful linear actuator. The instructions are a little tricky to follow, however the basic idea is to use the servo motor as a high-torque gearbox, which is then used to turn a screw to raise or lower your load. Using this method, he claims to be able to lift a 10kg load, which is pretty impressive!