Knex Inverted Helix Lift

Introduction: Knex Inverted Helix Lift

About: On my page you'll find lots of different Knex projects, from ball machine lifts to useful items. I hope you enjoy!  _______________________ Current avatar: Target of my skeeball machine Past avatars...

Hello everyone! This is a lift for ball machines, and it's an inverted helix lift. This lift was first featured in Cataclysm (last picture shows it). It's similar to a regular double helix lift, except the tower rotates in the middle, and the helix is on the outside! Of course, there's still a tower on the outside supporting the helix.

This lift is much better than the double helix lift, because you can make it very high, since the tower in the middle is much stronger than a double helix. It's more smooth, and more fun to watch, too. :-) It does use a lot of pieces though.

Note: You can also make this lift with one strand of tubing instead of two. This way you'll use less orange-tabbed connectors and tubing. Go to step 2 for details.

This is different than the original used in Cataclysm. It uses much less pieces. If you have enough, you can make it as big and piece-consuming as you want.

Here is a video of the inverted helix lift in action!

Note: This lift does not work with newer Knex balls (balls from Motorized Madness, Big Air Ball Tower, etc.) because they are too big.

Step 1: Parts Count

Here's all the pieces that this lift uses.

Rods: 313
  • green-127
  • white-64
  • blue-59
  • yellow-34
  • red-11
  • gray-18
Connectors: 231
  • dark gray-20
  • light gray-3
  • red-22
  • green-7
  • yellow-58
  • orange-tabbed-32
  • white-9
  • orange-8
  • blue-29
  • purple-43
Other: 35
  • Y-clip-6
  • tan clip-3
  • blue spacer-16
  • silver spacer-7
  • battery-powered motor-1
  • strands of tubing-2: one 6 feet 3.5 inches long (191.77 cm), and the other 6 feet 4 inches long (193.04 cm). You don't have to cut the tubing, but it is recommended that you do. Go to Step 7 for details.
Total: 579

And you'll also need original Knex balls.

If you have enough pieces, then let's get building!

Step 2: Using Only 1 Strand of Tubing

Before you begin to build, you'll want to decide on if you'll use two strands of tubing or one. This lift uses a top strand of tubing and a bottom strand of tubing, but it's possible to only build the bottom strand and leave out the top strand. This will save on pieces. I've never tried this method myself, but Sorunome and Koolcoasterkid have tried it. You will most likely have to modify the exit track like in the above pictures. Also, keep in mind that this method isn't too developed yet. With Sorunome's lift it can go the same speed that my lift goes, but Koolcoasterkid had to make his go slower because balls were falling out. Using one strand is worth trying out though. If you decide to use one strand, refer back to this step to make sure things are modified well. The rest of this Instructable will show you how to make the two strand version.

To make it with two strands of tubing: Ignore any modifications in this step and move on to step 3.

To make it with one strand of tubing: Go through the Instructable as you normally would, starting at step 3, but refer back to this step to see the modifications. The only things different are the lack of the top strand and the exit track.

Pictures 1-4 are Sorunome's lift and pictures 5-8 are Koolcoasterkid's lift, showing the modified exit track.

Step 3: Base and Middle Tower, Part 1

First off, you'll begin with the base and middle tower (the rotating part). The base floor is the section that the ball rolls on before being lifted up. You're only building part of the middle tower in this step.

Pic. 1- Build the base floor.
Pic. 2- Another view of the center.
Pic. 3- Don't forget all the spacers!
Pic. 4- Bottom view.
Pic. 5- Build this middle tower section.
Pic. 6- Another view.
Pic. 7- Another view.
Pic. 8- Build these bits.
Pic. 9- Another view.
Pic. 10- Attach them onto each side like so.
Pic. 11- The yellow rods should be connected to two orange connectors on each side, and a blue connector near the middle.
Pic. 12- Another view.

Step 4: Base and Middle Tower, Part 2

Now you'll build more of the middle tower. Once you finish the long section (pictures 1-4), you'll attach it to the middle tower section you made in the last step. Then you'll finish it off with two long rod-like things. After that, you'll make the rest of the base, including the motor. It's important that you include the grey rods going up the middle (pictures 7-9). Without them the balls will get stuck.

Pic. 1- Build this long section for the middle tower.
Pic. 2- Close-up of the tip.
Pic. 3- Another view of the section.
Pic. 4- Another view.
Pic. 5- Get the section you built in the last step.
Pic. 6- Attach them together like this.
Pic. 7- Now build these.
Pic. 8- Attach them to each side of the middle tower. Each side is held in with blue connectors.
Pic. 9- Another view.
Pic. 10- Get the motor, and add pieces to it. Make sure the yellow rods and blue spacers that are on the battery pack don't slide off. Two blue spacers won't go anywhere yet.
Pic. 11- Build the bottom part of the base.
Pic. 12- Another view.
Pic. 13- Another view of the center. Those two blue connectors should be facing in that direction!

Step 5: Assemble the Base and Middle Tower

Next, attach all of the sections of the base and middle tower together. First you'll slide the middle tower through the base floor (pictures 2 and 3). Then you'll add the motor (pictures 4 and 5). Lastly, you will attach the bottom of the base (pictures 6-9).

Pic. 1- Gather all of the sections that you have built so far.
Pic. 2- Slide the yellow rod of the middle tower through the white connector at the center of the base floor.
Pic. 3- Another view.
Pic. 4- Add the motor to the yellow rod of the middle tower. There should be a blue spacer on each side of the motor. The blue rod should slide into the orange connector, as shown in the picture.
Pic. 5- Add the battery pack to the base floor.
Pic. 6- Now attach the bottom of the base. The side with the green connectors should be with the side of the base floor that has the dark gray connectors. Make sure you connect all connections!
Pic. 7- Another view. Notice the yellow rod and blue rod sticking out of the connectors that they slide through.
Pic. 8- Another view.
Pic. 9- Another view.

Step 6: Outside Tower

Now you will build the tower outside tower. It comes in two sections, which will then be connected to each other. Make sure the rods that are connected to the orange-tabbed connectors are like the ones in the pictures!

Pic. 1- Build this section of the tower.
Pic. 2- Another view.
Pic. 3- View of the orange-tabbed connector side.
Pic. 4- Close-up.
Pic. 5- Another view of the orange-tabbed connectors.
Pic. 6- Back view of the section.
Pic. 7- Now build this section, which is similar to the section you just built.
Pic. 8- Another view.
Pic. 9- Another view.
Pic. 10- View of the orange-tabbed connector side.
Pic. 11- Close-up.
Pic. 12- Another view.
Pic. 13- Another view.
Pic. 14- View of the back side.
Pic. 15- Another view.
Pic. 16- Now get both the sections of the tower.
Pic. 17- Attach them together like this.
Pic. 18- View of the top end.
Pic. 19- View of the bottom end.

Step 7: Attach the Tower and Base

Now that you've built the outside tower, you will attach it to the base and middle tower. Then you'll top it off with the top section, which will secure the middle tower.

Pic. 1- Get all of what you've built so far.
Pic. 2- Attach the outside tower to the base. The side of the tower with the dark gray connectors sticking out should be lined up with the side of the base that has the green connectors at the bottom.
Pic. 3- View of bottom connections.
Pic. 4- View of the back.
Pic. 5- Another view.
Pic. 6- Now build this top section. Grab 3 blue spacers and a tan clip.
Pic. 7- Slide one of the blue spacers onto the white rod at the top of the middle tower.
Pic. 8- Connect the top, and put 2 blue spacers and the tan clip on the white rod.
Pic. 9- Looking down the front from the top. Notice where the green connector at the top is!

Step 8: Add Tubing

Get your two pieces of tubing. It is recommended that one is 6 feet, 3.5 inches long, and one is 6 feet, 4 inches long. If you don't want to cut it, then that's okay. First you'll install the top strand (the one that's 6 ft, 4 in. long). Start at the bottom, because it's able to stick out at the top. Then you'll install the bottom strand (the one that's 6 ft, 3.5in. long). Make sure the tubing is circular inside the tower. The extra tubing supports connect to the bottom strand of tubing.

Pic. 1- Start the top strand of tubing at the bottom.
Pic. 2- Then attach it to more orange-tabbed connectors. It may help to take out some gray rods on the support tower, so it'll be easier to run the tubing through.
Pic. 3- The top strand of tubing should be like this.
Pic. 4- At the top, the tubing is able to extend out as much as you want, if you don't want to cut it. It should rest on the green connector. This helps it curve better.
Pic. 5- Another view of the top strand connected.
Pic. 6- Now begin with the bottom strand. Put the end on the white rod.
Pic. 7- The bottom strand is finished in this picture.
Pic. 8- The top of the bottom strand extends out like this.
Pic. 9- View of a small tubing support.
Pic- 10- Another view of the completed tubing.

Step 9: Track and Supports

In this step you'll finish it all off. First there's a small support to help curve the tubing, and then enter and exit tracks.

Pic. 1- Build this small support.
Pic. 2- Connect it to the bottom part of tubing like in the picture. The yellow rod should keep it there. This helps the bottom part of tubing curve better.
Pic. 3- Now build the entrance track.
Pic. 4- Another view.
Pic. 5- Connect it to the base.
Pic. 6- Another view.
Pic. 7- View of the bottom of the track. The red tubing and white rod should fit underneath it.
Pic. 8- Build this small bit.
Pic. 9- Attach it to the top. The light gray connector is slightly under the tubing, and it is supported with tubing underneath.
Pic. 10- Now build the exit track.
Pic. 11- Another view.
Pic. 12- Connect the exit track to the top.
Pic. 13- Another view. Notice the tubing, which is on top of the track.

Step 10: You Are Done, Yay!

Congrats, you are finished with my inverted helix lift! Get some balls and load them into the entrance track. Turn the motor on, and watch it go! If the balls fall down as they go up, then you need to tighten the tubing around where it falls.

If you build it, send me a picture, and I'll put it on this step! :-) Be sure to give me credit if you post pictures/video elsewhere.

If you have enough pieces, you can modify it, like making it higher, and adding more orange-tabbed connectors to support the tubing.

Thanks for viewing, and don't forget to comment, rate, and subscribe!

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153 Discussions


2 years ago

I made it! It took around 15 minuets to get the tubing just right. Now it works perfectly. Thanks for the clean instructions.


Reply 2 years ago

Awesome, thanks for building!


Reply 2 years ago

Right now I'm making it twice the height. When I'm done I'll download a picture.


Reply 7 years ago on Introduction

they are right next to each other on the keyboard :P


7 years ago on Introduction

i can`t build this i only have the newer balls :-(


8 years ago on Step 8

hey shadowman I'm having a bit of trouble with the tubing because the ball keeps slipping through the tubing when the balls are close but when the balls are more spaced they work fine. also it doesn't work when there are balls on both sides so i can only use one side. Do you suggest anything to try and fix it?