Citadel Knex Ball Machine





Introduction: Citadel Knex Ball Machine

Hello everyone! After 3 years, my ball machine Citadel is finally finished! This machine features around 50 new elements, 5 different lifts, and 2 new path separators that separate into 17 paths. It's also themed, with Knex men all over the place working on it, giving it a factory-type feel with catwalks and stairs. There are 3 total motors, one of which powers all 3 floor lifts. The actual time it took to build is one year, there was just a long break in between. All of the paths (except one) were built in 6 months, starting in December 2015. I hope you enjoy!

Here are the element instructions!

Click here for more pictures!

Here's the video:

Here's the construction album.


Started building: Jan. 21, 2013

Finished building: June 20, 2016

Height: 8 feet

Width: 5 feet 3 inches

Depth: 4 feet 2 inches

Pieces: 50,000 - 60,000

Thanks for viewing!



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    Do you have instructions for the ball selector?

    Can you get me instructions for the elements at 1:25, 2:17, and 3:28? I know you are busy, but it would be much appreciated if you could get instructions or lots of pictures for them. I am going to make a medium sized ball machine and would love to have these in it. Thanks!

    Are you making a knex ball machine out of those?

    I won't make it with those, but yes, I am making a ball machine. The reason I won't use those is there wasn't very good pictures.

    Ya. I got some too. They aern't very detailed but I still made them.

    Alright, I sent you a PM with the links.

    How are the instructions for the elements/lifts coming along? Do you have an idea on when they would be posted? I've been trying to re-build the jigsaw lift with the pictures given on your Flickr page. I was able to figure out the design and of the lift, but I'm now struggling with motorizing it.