K'nex Gearbox





Introduction: K'nex Gearbox

This instructable will show you how to build a K'nex 1 speed gearbox that will make a motor go faster/slower. This is my first instructable sorry if it is unclear and some of the pictures are blurry.
p.s it is based on a gearbox that I found on Youtube its here if you want to see it.
pp.s Give credit to spoonman192
ppp.s remember to use SANYO eneloop Batterys for the motor.

Step 1: The Base

Firstly build the base.

Step 2: The Gears

Now the tricky part, insert the gears as shown.

Step 3: Strengthening the Gearbox

Now to strengthen the gearbox and the basics of the motor.



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    Hey gingernutsjonny, check my gearbox! It has just been posted. It's made for functional purposes and works awesome.

    hey i found that using the fast gear for around every one turn its around 15!!!!!!on the other (slow option)so thats like if you ue a 1000rpm drill you be getting 15000!!!!!!!!rpm on the other end imaging that on a roller coaster chain lift!

    amazing love it thanks for the instructions!

    make a part list please

    I built this once and it makes the last part spin really fast. then I hooked up my 1350 rpm drill to it and all the pieces twisted up and I had to throw it away but it was worth it

    i tried building this once and it did not work

    1 reply

    The problem with this is that (if it has 3 blue gears) it is pushing the limits of a K'nex engine (except the mains powered one) as more friction is generated and the torque required to get the whole gearbox moving increases dramatically. Because of this I think you'll find that with just 2 blue gears you get similar performance. It's also better for hand cranked stuff like ferris wheels or windmills. I made a gearbox too (check out my account, click my icon) but really big so you can see the inner workings!

    zomg i cant believe this. ive not seen this thing for ages im spoonman192 i made this years ago before i made my youtube account omg cool for posting it i remember telliung a guy i would but i forgot so thanks!

    1 reply

    i have removed my knex gearbox video now so u cant see it anymore this is spoonman192 btw

    Haha, that sounds hilarious.

    The 'if you want a good tranny' bit.


    make a huge one and see how fast it goes with a speedometer :D

    2 replies

    tried to make my own, accidently made a 60 second timer :D