Sliding Arm Lift, a knex ball machine lift - YouTube
This K'Nex Machine Is 23 Feet Tall And Has Over 100,000 Pieces | Smart News| Smithsonian Magazine
K'nex: Seesaw Instructable | knextus
I just finished my latest K'nex Ball Machine, currently on display at The Works Museum in Minnesota! It stands 23 feet tall and has 115,000 pieces. : r/KNEX