Microscopic: Mini Knex Ball Machine

Introduction: Microscopic: Mini Knex Ball Machine

About: I can do all things through Christ which strengtheneth me. Philippians 4 13

I am making a series of weird knex ball machines, and this is the first! Although it is pointless, it is tiny, really tiny. Actually, it is the smallest ball machine ever! (smallest piece wise, that is)

A few years back I think there was some challenge to make a ball machine in a red rod by red rod box. Lots of people were doubting that it was possible, but then one guy actually did complete that challenge. I can't find it now, if someone remembers it please say. Anyway, I thought of taking that challenge farther and making a ball machine in a yellow rod by yellow rod box! Here is the result. The motor and a few other pieces go a tiny bit out of the box but nothing goes way out of it, except the ball when it pops up.

What is pretty cool about this ball machine is that it is the first ball machine to have under 100 pieces! The ball machine that is the next smallest is Sorunome's Micro BM, which has 118 pieces. This one has 87 pieces! That means this ball machine is 31 pieces smaller than the next smallest!

Step 1: Parts Count

Here are the parts and pieces needed to make this BM:


Dark Grey - 5

Green - 2

3D purple - 19

Orange - 3

Red - 1

Yellow - 4

3D Blue - 1

White - 3


Green - 6

White - 15

Blue - 8

Yellow - 9


Silver Spacer - 1

Blue Spacer - 2

Y-Clip - 2

Tan-clip - 2

Metallic Blue Clip* - 2

Ball - 1

Green Motor - 1

Total: 87

*If you don't have these, tan clips will work.

Step 2: Starting the Box

In this step you will start miking the box, or body, for the BM. Try to make everything the exact same as the pics, like everything pointing the right way, cause it is important. The notes in the pictures will help you a bunch.

Step 3: Adding the Motor

In this step you will add the motor. It is a pretty simple process, but the stuff you put on the rod could slide off before you fasten it, so watch out for that.

Step 4: Adding Everything Else

In this step you will add all the bits and pieces that you didn't add yet. Some of the pictures don't make a whole lot of sense, but the notes should help a little.

Step 5: Done!

Done with the smallest BM ever! It was pretty easy, now wasn't it? BTW the switch always goes TOWARD the middle.

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Box Contest 2017

Participated in the
Box Contest 2017

1 Person Made This Project!


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2 months ago

lol this is awesome 😂