Pulley System for Easy Lifting
I’ve always wanted to make a “complex system of ropes and pulleys” to do some work. Well this is not complex, but it is a system of ropes and pulleys. Anyway, it is the method I initially used to lift passengers to the top of the hill.
I’m using a 3/8″ nylon rope, but I would encourage you to use at least 1/2″ rope for your design. The larger the rope diameter, the less it digs into your hands and the easier it is to pull. I started off with a 3:1 system, but I had enough rope to do a 4:1. This lowered the needed force from 45 lb to 34 lb. A significant reduction. Another benefit of this is when the cart is stowed, I can connect the free end to the hook. The cart pulls against the rope hard enough to keep it off the ground.
Anti-Rollback Devices
It is critical that the cart not be able to roll backwards down the lift hill. This prevents injury from collision or damage to the track. I have 10 simple levers that act as our roll back prevention devices. As a result the cart cannot roll backward more than 15 inches. Not only is this a safety mechanism, it also doubles as an easy way to rest the car while walking back to choke up on the lift rope.
Transverse Shear
In one week, I experienced 2 failures on the rollback prevention devices on the lift hill. Both cracked along the length of the 2 x 4. Why is this happening and how can we prevent it?