Knex Ball Machine 'scissor Arm' Element

This element uses a 'scissor lift' geometry to move the ball sideways while acting at a small arm.

Attached is a small video of it in use.

Step 1: Scaffold

Here is the important part of the scaffold. Don't worry if it doesn't balance like in the first picture, as I added hidden unneeded pieces to hold it up.

Step 2: Pivot and Counterweight

This part holds the pivot point and the counterweight. I used 2 pulleys (1 1/2 in), 1 snap-on hub (1 1/2 in), and 1 tire (1 1/2 in).

Step 3: Scissor, Wheels, and Ball Holder

I have not tested other sized scissors, but if you do then you should build a further track in step 1.

After this step you are done! Good job