Knex Elevator Free Fall Lift




About: Hi, I'm KneXtreme. I'm a Christian and I'm home schooled. I love to build with almost anything especially knex. I also do Taekwondo and collect coins. Just so you know, I don't hang around youtube ...

Hello everybody.
     I got the inspiration for this lift after seeing Alocke's ball machine Tartarus. As you can guess by the name, when the car gets up to the top it suddenly free falls. This is do to the special gearing mechanism. I modified a medium knex gear by taking off some of the teeth leaving only 17 left.  When the teeth of the medium gear catch hold of the small gear (see picture 10) it turns the shaft which is connect to a wheel-like device which winds in the string (or chain) connect to the car thus pulling the car up. When the car gets up to the top there are no more teeth turning the blue gear thus making the car fall. Enjoy the video.

Step 1: The Base

Step 2: The Track Part 1

Step 3: The Track Part 2

Step 4: The Entrance

Step 5: The Wheel and Crankshaft

Step 6: The Bottom Side

Step 7: The Gearing Mechanism

     For this step you will have to modify two knex parts, a tan locking clip and a medium gear with teeth. You'll have to sand down the top part of a tan locking clip so that it doesn't rub against the black hinge half. (see picture 6 and 7) You'll also have to take off 17 teeth on a medium size gear so that only 17 teeth remain. (see picture 6 and 7)

Step 8: The Exit

Step 9: The Elevator

     For this step you can either use string, fishing line, or mini chain links as seen in the last three pictures. Make sure you cut the string (or fishing line) just long enough so that the elevator touches the ground. Sorry, I forgot to count how many mini chain links to use.

Step 10: The Back Support

Step 11: The Sides Part 1

Step 12: The Sides Part 2

Step 13: All Done!

Congrats! You've finished the elevator free fall lift. Make sure you flip the switch to the left or it won't work.



    • Woodworking Contest

      Woodworking Contest
    • Pocket Sized Contest

      Pocket Sized Contest
    • Fat Challenge

      Fat Challenge

    55 Discussions


    6 years ago on Introduction

    This IS pretty cool! But the reason you didn't use an orange gear is because you probably don't have the drop n swing right?

    2 replies

    Reply 6 years ago on Introduction

    Thanks. I have the orange gear, but I didn't use it because I broke it testing the mechanism.

    I've built it and it works great. Instead of cutting of the teeth of a yellow gear, I used an orange gear. (I guess you know it)
    I'll use it in my next ball machine
    Thanks for this awesome lift!

    2 replies

    I'm sorry to ruin the fun but the mechanism is not original. A similar mechanism is on a knex amusement park series on a free fall ride that includes an orange gear but great job making it into a lift!

    1 reply