Ball Track - K'nex Compatible

Introduction: Ball Track - K'nex Compatible

I am a professional chain reaction builder and domino artist, called Sprice Machines. I was a quarterfinalist on America's Got Talent, a guest on The Rachael Ray Show, and have performed my machines on several other shows and at museums and schools across the US.

Right now, I am starting to design a standard building set for kids to easily build their own chain reaction tricks. The first piece I am designing is a Ball Track.

My goal was to create a ball track (the most basic element of all of my machines) that fits ping pong balls and golf balls, and is K'nex compatible; this allows you to easily create track connectors, inclines, and can be the basis for more complicated chain reaction tricks.

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Step 1: Step 1: CAD Model

Using the requirements below, I came up with the ideal dimensions to make the track meet all of my goals.

1. Can fit 40 mm ping pong ball

2. Can fit 42 mm golf ball

3. Wall height is tall enough to protect balls from rolling over the edge but not too tall to impede the ball from being able to easily roll onto the track

4. Yellow and Orange K'nex connectors can slide easily into a slot on the bottom of the track

5. Length of track is just under the length of the 3D printer's build size

Step 2: Step 2: Print

Next, I printed the track and this was one of the prototypes I came up with.

Step 3: Step 3: Quality Check

I checked if all of the design requirements were met. As the 3D print varied slightly from the model, it took me a few prototypes before I arrived with this one, which has the correct dimensions to fit the K'nex piece and balls.

Step 4: Step 4: More Chain Reaction Products

My goal is to use the slot underneath the track to connect more 3D printed parts which are designed to do certain chain reaction or domino tricks such as the ones that I have used in my past machines. Previously, there was no standard building set for this hobby, and I had to fit together many different items that certainly were not meant to be used for this purpose in order to do the tricks that I wanted to.

If you want to see some examples of these chain reaction machines, please visit:

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    7 Discussions

    That's a nice concept! How did the show go that you talked me about some time ago?


    Reply 4 years ago on Introduction

    Oh it never happened. They couldn't find any companies interested in sponsoring it.


    5 years ago

    I think it's really cool how you have designed this to work with two different kinds of balls and how it is compatible with knex. I also saw that you were the knex fan of the month. Well done!


    5 years ago on Introduction

    This is a pretty cool idea! About how long does it take to print one section of track?


    Reply 5 years ago

    I'm not sure. I had my friend print it but my dream is to get (or win!) my own 3d printer someday so i can continue designing my product set