here are instructions for a Knex Ball Machine Lift (The Dubble Stair Lift).
This lift can handle 3 knex balls at the same time and is really easy to make and works very smooth when instructions are carefully followed. Just make sure you have a 12V motor and enough Medium red (grey or yellow) gears, because you'll need about 24 of them. You can also check Step nr1 to see the special pieces you need to complete this build. If you don't have the pieces that you see in Step 1, don't worry, you can easily build this lift without them, it just makes the lift a bit more steady.
If you are interested in making a longer version of this lift, I recommend you to aply a second 12V motor on the top of the lift for a smoother rotation.
If there are any complains, questions or problems, please tell me in the comments below.
Thanks for watching, building,
Step 1: Special Pieces You Need:
Stop counting, there are 11 connectors and 21 spacers :p.
Step 5: Important Step:
Make sure that all the black connectors are facing downwards.
11 connectors and 21 spacers.
Step 12: Another Important Step:
Now, make sure that all the black connectors are facing upwards.