Introduction: Separating Arm Lift, a Knex Ball Machine Lift

About: Hey! I'm Sandroknexmaster. I like building with knex, especially ball machines. I live in Belgium. I speak Dutch, but also English and French. I hope you like my stuff, and like always comment, rate & …


This are the instructions for the last new lift used in my knex ball machine Elysium.

Apart from being a lift, it also functions as a path separator. Each arm drops the ball at a different exit track.

If you watch the video of Elysium, you will notice some differences between the original and this version.

The balls don't enter in the center anymore, but all the way down at the end of the arms. This gives the lift a lot more height.

A new entrance system has also been added to make sure the balls enter correctly and one by one.

There are a lot of possibilities with this lift: You can change the direction of the exits, the side of the exits, the amount of arms,...

And more general, the idea of a lift system that works as a separator at the same time is also quite interesting. I'm curious to see what you can come up with.

If you're going to build this lift, please read every image note, they are very useful! Especially in step 7 where we are going to build the arms.

When you encounter a problem or have a question, you can always send me a message.

Thanks for watching / building!


Step 1: Piece Count

If you want you can count the pieces before you start building.

Here is a list with all pieces included in this lift, named by their original colour:


Green: 673

White: 187

Blue: 235

Yellow: 124

Red: 512

Grey: 100

*Black: 1

Total rods: 1832


Dark-grey: 57

Light-grey: 25

Orange: 55

Red: 92

Green: 36

Yellow: 184

White: 203

Purple: 596

Blue: 70

Total connectors: 1318


Blue spacer: 99

Silver spacer: 86

Tan clip: 10

Y-clip: 42

**Small blue gear: 7

Medium red gear: 1

Big yellow gear: 3

Motor: 1

Total other: 249

Grand Total: 3399

*It's recommended to use a black rod for the axle, a grey rod might bend too much.

**In the 5th step, the axle, there are 4 small brown-gold gears. This is not their original colour, but they are included in the piece count under 'small blue gear'. Further explanation can be found in the 5th step.

Step 2: Entrance Part 1

The first part of the entrance, where the balls enter the lift.

Step 3: Entrance Part 2

The second part of the entrance.

Step 4: Support Towers

Two support towers, pretty boring to build but very necessary!

Step 5: Axle

This part will hold all the arms in place. The small gears can't have too much grip. They have to rotate without the yellow rods rotating with them. These brown-gold coloured gears are perfect, but some other blue and grey ones work as well. You'll have to search through your collection of small gears to find the most suitable gears.

Step 6: Gears

Now we will build the rest of the gears. This part also helps to keep the axle in place.

Step 7: Arms

The arms. Read every image note in this step, it will be easier to follow.

Step 8: Exits

The 8 exit tracks for this lift. You can choose the direction of the tracks yourself.

Step 9: Exit Support Tower

Another support tower at the top of the lift.

Step 10: Motor

The last step! It's time to add the motor.

Step 11: Finished!

You just finished the Separating Arm Lift!

Always slide the switch of the motor to the right.

Thanks for watching / building!


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