Most automated boat lifts rely on electric motors, but as most engineers and boat-lift repair personnel know, electricity and water don’t mix.
To alleviate the risk of shock associated with lifts, Prof. Gary Kurtz and an engineering student at Purdue University built the only known pneumatic boat lift. It is based on a standard friction-drive lift, but pneumatics rather than electricity powers it. The rig uses a standard air compressor located about 60 ft from the dock, though it has been tested with the compressor 250 ft away. A 1.25-in. ID water line sends compressed air to the dock where it feeds into a three-position return-spring, manually operated directional valve. Two lines from the valve power a pneumatic motor that has its shaft connected to the boat-lift’s friction wheel. The lift can raise a 3,000-lb boat and costs about $700.
An air-powered lift takes boats out of the water without risk of electrical shock.