Sliding Arm Lift, a Knex Ball Machine Lift





Introduction: Sliding Arm Lift, a Knex Ball Machine Lift

Hi everyone!

I bring you the instructions for the third new lift first used in my knex ball machine Elysium, the Sliding Arm Lift.

In fact, this lift was used twice in the machine, both were similar.

This is a small, simple lift, and nice to watch.

Its name refers to the arm sliding down every time it has lifted up a ball. This feature is actually really useful and not only a fun extra. The best example I can give is Elysium itself. The second Sliding Arm Lift in the video is located very close to the Ferris Wheel Lift. A normal arm lift could not be placed there, because the arms would have touched the ferris wheel.

The arm uses two black rods. I tested the lift with grey rods instead of black, and it didn't work properly, so the black rods are necessary.

If you build this lift, don't forget to read the image notes in step 5: Arm and Axle, they can be useful. When you have a question or problems while building, feel free to make a comment or 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: 17

White: 17

Blue: 29

Yellow: 12

Red: 6

Grey: 2

Black: 2

Medium flexi: 2

Long flexi: 2

Total rods: 89


Dark-grey: 11

Light-grey: 8

Orange: 8

Red: 12

Yellow: 25

White: 6

Purple: 13

Blue: 1

Total connectors: 84


Blue spacer: 5

Silver spacer: 6

Tan clip: 5

Y-clip: 4

Small blue gear: 2

Medium red gear: 2

Motor: 1

Total other: 25

Grand Total: 198

Step 2: Entrance Track

This is the track the balls will follow.

Step 3: Motor and Gears

As the title says, this step shows how to make the motor and gears section.

Step 4: Frame and Exit

The frame and the exit in one step, it's not too big for this lift.

Step 5: Arm and Axle

Look closesly to the pictures. The axle is a bit complicated, but the pictures in this step should help.

Step 6: Finished!

Your Sliding Arm Lift is finished!

Always slide the switch of the motor to the right.

Thanks for watching / building!




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it looks awesome, now i will try it on my totally different ball machine that i built out of a knex rod sorter

I'm going to put this on my ball machine! THANK YOU! Built and done!

very nice! straightforward to build and not too many pieces. I will challenge my advanced kinder students (5 yr olds) to try. Only part I know they can't do is snap the axle.

Thanks, wonderful to read your comment! Did they succeed? :)

Yes they were very proud of it! One of them said, what he liked best about making it is it was hard, it challenged him and he likes a challenge.