Introduction: Knex Alternator Lift

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Hello everyone! This is an Instructable of a new ball machine lift, the Alternator Lift!

This is a lift I made and worked on for a month. Here's how it works: a tower in the middle of the main tower (called the lifter) has ball grabbers on it. There are ball holders built into the front of the tower. When the lifter goes up and down, the balls are alternated from one side to the other, which is why I named it the Alternator Lift!
This lift does not fit balls from Motorized Madness, Big Air Ball Tower, or Loopin' Lizard.

Fun fact: this Instructable has over 211 pictures.

So, if you want to build it, move on to Step 1!  :-D

I hope you like it!

Video of the lift in action:

Step 1: Parts List

These are all the parts you'll need to build the Alternator Lift.


Rods: 617

  • green-200
  • white-123
  • blue-200
  • yellow-76
  • red-10
  • gray-6
  • tan rigid-2

Connectors: 457

  • dark gray-34
  • light gray-25
  • red-66
  • green-27
  • yellow-101
  • white-21
  • orange-33
  • blue-58
  • purple-92

Other: 145

  • blue spacer-67
  • silver spacer-38
  • red gear-1
  • blue/tan gear-1
  • ball joint-2
  • ball socket-1
  • black/light green hinge-1
  • tan clip-6
  • blue clip-2
  • Y clip-17
  • small wheel-4
  • rubber band-3
  • 1 strand of string, 40 inches (102 cm) long
  • battery-powered motor-1

Total: 1219

And, of course, you'll need original Knex balls.

If you have all these pieces, then move on to the next step! If you don't, then...  buy some more. :-P

Step 2: Before You Begin

Before you begin on your quest, you need to see this step. The first picture shows the many sections that you'll be building. The second shows what side is front, back, and all that. It's important to know all the stuff in the second picture. The front is the side with the ball holders, and there's also the right, left, back, bottom, and top. Those places are obvious, but I put some image notes in there anyway.

Once you've seen all that, you can finally start building!

Step 3: Tower Base, Part 1

To begin with, you'll build one side of the tower's base. The side with the connectors that have green rods on them is the front (this goes for the whole tower). This section of the tower will be on the right side that holds the motor.

Step 4: Tower Base, Part 2

Here you'll build the other side of the tower that complements the section you made in step 3. It's the left side of the tower.

Step 5: Assemble the Base of the Tower

Now you'll attach part 1 and part 2 together to form the tower's base.

Step 6: Grabbers

These push the balls up. They will attach to the lifter, which will go up and down to grab the balls.

First, build the normal grabber (pictures 1-4). You'll build four of them.

Then, you'll build the bottom grabber, which is different from the others. It's divided into Part A and Part B (Part A is pictures 5 and 6, and Part B is pictures 7-10). Then you'll combine those to complete Step 6.

Step 7: Lifter

This is the lifter. It will hold the grabbers. Build it.

Step 8: Attach the Grabbers to the Lifter

Now you'll attach the grabbers you built in Step 6 to the lifter. You'll also need 6 blue rods, which connect in between the grabbers.

Step 9: Add the Lifter to the Base of the Tower

Now that the lifter and its grabbers are complete, you can attach it to the tower's base. The blue rods sticking out of the bottom of the lifter will connect to trios of red connectors. Make sure that the blue rods are on the middle red connector! (The fifth picture shows this.) The whole lift will fail if you don't do that. Also, the grabbers should be facing the front.

Step 10: Tower Middle, Part 1

Here you'll build Part 1 of the tower's middle section. It'll be on the right side. The blue rod connected to the trio of red connectors will also be on the middle connector.

Step 11: Tower Middle, Part 2

This is the other side of the middle of the tower (the left side).

Step 12: Assemble the Middle of the Tower

Combine Parts 1 and 2 together to complete the tower's middle section. They only connect in two places, in the bottom corner. Then you will complete the middle of the tower.

Step 13: Attach the Middle to the Base

Now you'll combing the tower's middle to the rest of the model. Remember to slide the thing in the back onto the gray rods (refer to picture 4). Also, don't forget to connect the lifter to the blue rod (picture 4).

Step 14: Tower Top, Part 1

This is Part 1 of the Top. It'll go on the left side.

Step 15: Tower Top, Part 2

Build the right side of the Top.

Step 16: Tower Top, Part 3

This is the final part of the tower's top. It will hold the string that lifts the column up and down.

Step 17: Assemble the Top of the Tower

Here you'll combine what you've built in steps 14-16. Pictures 2 and 3 show Parts 1 and 2 combined. Pictures 4 and 5 show Part 3 added.

Step 18: Attach the Top to the Middle

Now attach the tower's top to the middle.

Step 19: Left Support

This support will attach to the left side of the tower. Build it, and then attach it.

Step 20: Ball Holders

These are similar to the ball grabbers, except they don't go up and down. Build three normal holders, and attach one to a different kind of holder (pictures 3-6).

Step 21: Attach the Holders to the Tower

Now you'll connect the holders to the front side of the tower. Make sure the holders rest on the green rods.

Step 22: Side Supports

These supports go on the sides of the tower. The one with a white connector at the bottom goes on the right side, and the other one goes on the left side.

Step 23: Ball Entrance, Part 1

Now you'll begin the entrance where the ball enters the lift.

Step 24: Ball Entrance, Part 2

This is a track piece. It's broken up into two parts so it's easier for you to build. 

After you build it, you'll combine it with Part 1.

Step 25: Ball Entrance, Part 3

This will fit underneath the track, and will push balls into the lift. You'll need a rubber band for this step. After you build it, you'll attach it to the rest of the entrance. It won't function properly yet, but put the rubber band on like it is in the pictures. It goes around the green rod and purple connector.

Step 26: Ball Entrance, Part 4

This is a piece of track that the ball will go on before being picked up by the bottom grabber. After you build it, connect it to the rest of the entrance. Notice that the black ball socket goes in between two blue rods on the track. After you're done, the ball entrance will be complete.

Step 27: Attach the Entrance to the Tower

Now you'll attach the entrance to the front of the tower. Make sure to connect all the rods to the connectors.

Step 28: Ball Exit

This piece of track is where the ball will exit the lift. After you build it, attach it to the top of the tower.

Step 29: Back Support, Part 1

This will support the back of the lift.

Step 30: Attach the Back Support to the Tower

Now connect the support to the back of the tower.

Step 31: Wheels

These are two small wheels that the string will go through. Build them, and then attach them to the back/top of the tower. The yellow rods should be sticking out all the way towards the back (picture 3 shows this).

Step 32: Back Support, Part 2

This will complete the back support. After you build it, attach it to the back/base of the tower.

Step 33: Motor Section, Part 1

This part of the motor section will hold the red battery pack.

Step 34: Motor Section, Part 2

This part has the motor and gears.

Step 35: Motor Section, Part 3

This is the third and final part of the motor section. It has the crank and rubber bands.

Step 36: Combine and Attach the Motor Section

Now you'll combine all three parts together, and then attach the whole section to the right/base of the tower.

Step 37: String

Get the string. It can be any kind, as long as it isn't stretchy (I used fishing line). Make sure it's the same length of what it says in the parts list. When you tie it onto the blue rod, put it in between the two blue spacers. The other end shouldn't be tied to anything yet.

Step 38: Attach the String to the Lifter

Here you'll put the string onto the lifter. You may need to remove a few rods to reach in there.

Then, put the string through the four wheels (picture 2).

Step 39: Tie the Other End of the String

First, get a dark gray connector. Attach it to the crank (picture 2). Also, put the crank in its uppermost position (picture 2). Then, tie the string to the dark gray connector. The lifter should be all the way down. The string should be a tight fit.

Step 40: Ball Pusher

You're almost done! Just build the ball pusher, which will push the ball to the exit when it gets to the top. Then attach it to the top of the tower.

Step 41: Finished!

Congrats, you are now done with the Alternator Lift! Now go add it to a ball machine, or turn it on, add balls, and watch it work! If you use it in a ball machine, be sure to give me credit. ;-)

It is highly recommended to do this when you won't be using the lift for a long time. Unattach the dark gray connector with the string tied on it, and put the crank in its downmost position. This will prevent the string and rubber bands from stretching out over time. Refer to picture 4 for that.

Thanks for building, and don't forget to comment, rate, and Subscribe!