Introduction: Knex Flimsy Connected Arm Ball Lift

About: I'm into knex ball machine stuff. My favourite parts are lift/element hybrids, probably because I tried building a perpetual ball machine. It didn't work, of course. All my knex stuff is creative common, and …

This ball machine lift is great for if you want a fast lift system with a relatively small number of pieces. The only downside is that it is not very stable, but from my experience it is pretty reliable when running at the right speed.

These instructions show how to build a lift with 6 arms. I have not tested if this lift system can handle more arms.




Step 1: Scaffold

Basically, you're building a triangle. I got lazy so I didn't finish building it.

The scaffold is one blue rod wide. On all the blue rodes on the top of the triangle you should add some orange connectors that will hold the arms.

Step 2: The Arms

Most of the arms are identical, except there are 3 changes:

  1. In the bottom arm, the hand has extra pieces. This is used to pick up the ball for the first time.
  2. In one of the middle arms, the opposite side is more complicated. This is used to attach the arms to the motor.
  3. In the top arm, the counterweight is different. This is used to balance the arms.

Once you've built all the arms, attach them to the orange connectors in the scaffold, and connect the arms together using grey rods.

Step 3: The Motor

This is just a crankshaft.

I find that a green motor works at a nice quick speed for this lift.

Step 4: Entrance

Here is an example of a path that can load the ball into the lift.

The purpose of the wheel is to act as a counterweight, so if you don't have a wheel then use a handful of white connectors.

Step 5: The Exit

Here is an example of a path that can collect the ball at the top of the lift.