This is a simple version of 39shadowman's Modified Stepper Lift orginally built by Thibaultisthebest. This one is a remake of speedydog550's stepper and has instructions. Wow! What a surprise! This lift is based on the original stepper lift that was in a Knex set, except it doesn't use as much friction when the carts have to slide on rods. Instead, the carts are on small towers that are attached to axles.
HERE'S the lift IN ACTION: