Propulsion Knex Ball Machine





Introduction: Propulsion Knex Ball Machine

Hello everyone! This is my new, wide-scale k'nex ball machine Propulsion. This ball machine has a unique double rotating arm lift system, 6 paths, 3 motors, and 4 new elements with only 1 month of building and perusing (along with making the video).

What's special about this ball machine is that two paths are connected to the ledge of my house AND 2 of the 3 motors power 2 elements or lifts in unison, not just one. This was a fun project to build and that I built at least one particular element for each path!

Details for every part of this machine is analyzed in every step here to inspire those who might want to build something like this.

Here's the ball machine IN ACTION:

Step 1: The Floor, Lifts, & Return Track

This is the hub for all balls rolling off the various paths. A clever idea I had for the first part of this lift system has a backup track just in case there are collisions on the floor where the first rotating arm lift scoops the balls up. A mini chain lift helps transport the balls to the second rotating arm lift.

Step 2: Path 1

This is one of the paths I connected to the ledge of my house that has a moving path on it also. From there, gray rods have balls rolling to Knextreme's Panel Drop (motorized) and to a smaller, less-piece consuming variation of Kairah89's Zigzag element.

Step 3: Path 2 (2.1 & 2.2)

This is the other path connected to the ledge of my house that first leads to a Spinning Basket. After the basket drops the ball onto a super path, that leads to Sathothy's Two ball ball arm. The two ball arm then splits this path in half.

Step 4: Starting Path Connecting Paths 3 & 4

This portion of the machine connects paths 3 & 4 with 2 new elements of my own: A new type of ball arm and "rolling on connectors."

Step 5: Path 3

This path starts out with my one-and-only Mario Kart Paving in spiral form. The paving leads to Sorunome's long-lost Spinning Yellow Gear. When the balls rolls off the yellow gear, it'll land onto blue pathing that leads to a small ball arm.

Step 6: Path 4

This path starts out with a "rod-railed" path that leads to sandroknexmaster's Inverted Ball Dropper onto a Red Path. A variation of austron's tipping path is also included at the end of the path.

Step 7: Path 5

This features another lost element I found in Netchman's ball machine at 8:20 I modified to work with the newer balls. The path starts out with 2 ball alternators and momentum builds up as the ball rolls toward to what I'd like to call "the basket tilt beam." The ball will then land safely onto the side winder path.

Step 8: Path 6

This path features a new, less-piece consuming version of a trampoline, with that having well supports. It starts out with a ball arm lowering the ball to the red path transferring it to one of The96jonse's elements. More skinny path and a gravity shoot helps the ball (safely) bounce off the trampoline, with the floor being the designated target. 

Step 9: Gear Connections

As stated before, 2 of the 3 motors power 2 elements or lifts in unison, not just one. Well, here are some pictures to show you how all that works. One motor powers the two rotating arm lifts. The other motor powers the Panel Drop and the Spinning Yellow Gear.



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    nice zigzag mod!

    i remember watching this a while ago on youtube. nice machine!

    Everything you make is exceptional. And you give instructions, which not many people do. You are top of the line.

    Thank you!!! I appreciate it!! I got a new, massive ball machine in the works right now.

    I can't wait to see it. You are a fantastic designer. It must take you forever to build these things. I don't have enough knex to do anything even remotely close to them. Keep churning pieces out.

    Cool for it's size!

    Took me ages to find out how to finish a chain lift. Feel kind of stupid now.

    This is cool man. But could you repost it with a number count? Also does anybody else have to do the security thing?

    Cool! I like how the ball machine is spread out. It makes it easier to see every thing.