Introduction: Knex Elevator Free Fall Lift

Picture of Knex Elevator Free Fall Lift

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

Picture of The Base

Step 2: The Track Part 1

Picture of The Track Part 1

Step 3: The Track Part 2

Picture of The Track Part 2

Step 4: The Entrance

Picture of The Entrance

Step 5: The Wheel and Crankshaft

Picture of The Wheel and Crankshaft

Step 6: The Bottom Side

Picture of The Bottom Side

Step 7: The Gearing Mechanism

Picture of 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

Picture of The Exit

Step 9: The Elevator

Picture of 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

Picture of The Back Support

Step 11: The Sides Part 1

Picture of The Sides Part 1

Step 12: The Sides Part 2

Picture of The Sides Part 2

Step 13: All Done!

Picture of 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.


knepic (author)2015-04-28


dickheijboer (author)2013-06-20

Cool lift! I like the system! Can you make this higher?

KneXtreme (author)dickheijboer2013-06-22

Thanks! I don't know if you can make this version higher, but koolcoasterkid built something like it.

dickheijboer (author)KneXtreme2013-06-22

Yes, I saw that already! Yes, that's pretty cool! But that lift is not very much higher..

sandroknexmaster (author)2012-12-29

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!

Can't wait to see your ball machine!
Your welcome.

Ok but you will have to wait veeeery long, probably more then 2 months.

collinjo12 (author)2012-07-06

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?

KneXtreme (author)collinjo122012-07-08

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

knexgunbuilder217 (author)2012-06-25

does this require chain links

No, but you could use chain links instead of rope.

jameshond (author)2012-05-10

i have the orange gear can i use this it hase 16 teeths

KneXtreme (author)jameshond2012-05-11


jameshond (author)KneXtreme2012-05-11

oke thanks

jameshond (author)2012-04-28

how much rollercoaster conectors do i need for this lift

KneXtreme (author)jameshond2012-04-28


jameshond (author)KneXtreme2012-04-28


knexpert#10829476 (author)2012-04-17

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!

Thanks, but what amusement park ride was it on?

Sorunome (author)2012-04-12

Nice one! :)

KneXtreme (author)Sorunome2012-04-12

Thank you for my 400th comment.

Sorunome (author)KneXtreme2012-04-12

Haha, cool! :D

I_am_Canadian (author)2012-04-09

Now this is a fantastic bit of engineering. Very original design, I'd love to see it in a working machine.

Best thing on instructables for months :-)

KneXtreme (author)I_am_Canadian2012-04-10

Thanks. I'm planning on using it in my next ball machine.

Purple Waffles (author)2012-04-09

I think I'mma try and use this in my upcoming ball machine.

KneXtreme (author)Purple Waffles2012-04-10

Cool! It would be nice to see it in a working machine.

Kipcorn (author)2012-04-09

Knextreme, what a wonderfull lift again, I love your work, thanx for sharing!

KneXtreme (author)Kipcorn2012-04-10

Your welcome. I'm glad you like it :)

knexpert#10829476 (author)2012-04-10

Thank god that I don't have to modify that yellow gear because has orange gears that are just like the modified gear for those who don't know.

Alocke (author)2012-04-09

I'm glad I could inspire some new ideas :)

Kipcorn (author)2012-04-08

I live in Holland aswell and buy my parts @marktplaats. Give it a look, theres plenty for sale ;)

sathothy (author)Kipcorn2012-04-09

Yep, I treid doing that but my parents wont allow me to bidd on stuff that are over an 15 KM range. But I still trei. I never won(Is that how you say it?) something. But I'm only bussy doing that for an couple of months(like three).
Thanks for the help to!

Ja, dat doe ik al, maar mijn ouders willen niet dat ik op dingen bied die buiten een gebied van 15 KM zijn, maar ik probeer het nog wel . Ik heb nog nooit iets ''gewonnen''(Is dat hoe je het zegt?). Maar ik ook nog maar een paar maanden(ong. 3) bezig met dat doen.
Toch nog bedankt!

Kipcorn (author)sathothy2012-04-09

Hi Sathoty,
They can send it to you?

Je kan het toch laten opsturen? Kost je 6,75 tot 10kg. Scheelt je een hoop tijd en geld voor benzine. Is bij mij nog nooit fout gegaan. Succes!

sathothy (author)Kipcorn2012-04-09

Weet ik. Maar mijn ouders vertrouwen dat niet. Dus ze willen het ophalen.

sathothy (author)2012-04-07

Looks awesome! Do you have an video of it working?

KneXtreme (author)sathothy2012-04-07

Yes I do but my computer is running slow. I'll try to upload it tomorrow.

sathothy (author)KneXtreme2012-04-07

Ok. Cant wait! Also I'm ot going to build it cause I only have 2 yellow crown gears. But it looks awesome!

KneXtreme (author)sathothy2012-04-07

There is a special gear that already has the teeth cut off. It comes with a knex set called "Gear Action 20 model building set". I got mine for $20.

sathothy (author)KneXtreme2012-04-07

I know. Its that orange gear right? I also dont have that set and they dont sell it here.

KneXtreme (author)sathothy2012-04-07

Thats to bad :(

sathothy (author)KneXtreme2012-04-07

Yep. They actually dont sell knex in Holland(sometimes they do but that are sets whit only bricks or those amusement park series(they sell them for 40 euros(Around 52 dollars)))

KneXtreme (author)sathothy2012-04-08

Since you live in Holland try marktplaats.

sathothy (author)KneXtreme2012-04-09

I'm already doing that. Last week I bidded on an original coaster. But no one overbidded me and the seller didnt respond, maybe she/he doesnt accepts the bid, and there is no timeframe when like the auction ends.
And I just saw the video! Its even awesomer then I tought!

Purple Waffles (author)KneXtreme2012-04-07

Yeah I have that. Could i use that for this?

KneXtreme (author)Purple Waffles2012-04-08


sathothy (author)sathothy2012-04-07

And Don't have those origanal coaster connectors

KneXtreme (author)sathothy2012-04-08

Video is up.

Shadowman39 (author)2012-04-07

This is a cool idea! To make it taller, the gear would have to be different though right? (the one that's modified).

KneXtreme (author)Shadowman392012-04-08

Video is up.

Shadowman39 (author)KneXtreme2012-04-08

Now I know what the red connector wheel is for. :-P

About This Instructable




Bio: 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 ... More »
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