DenCity- a K'nex Ball Machine Instructions




 My latest and most piece- consuming build yet, more pieces than my pinball machine!This ball machine was the hardest to make instructions on since everything was so integrated into each other. DenCity although being dense and all also has 6910 pieces, five paths, a motor that drives four mechanisms, thirty-nine gears and a wide structure. DenCity started out when I made Ionization and decided to keep the gate and lift system and build a new ball machine around it. Then I thought, " how many things can I power with one motor?" This is what came out. A lot of elements came from other member's guides.

This instructable is currently in beta as of descriptions of the paths but all the photos are uploaded.

Also, this is the first instructable where I cropped all the pictures!

Credit goes to yardking42 and Martijnb95 for use of some of their elements.

Step 1: Piece Count


Grey: 27
Red: 148
Yellow: 377
Blue: 988
White: 617
Green: 1198!

TOTAL: 3,355


White: 172
Blue 3D: 265
Yellow: 746
Green: 102
Purple 3D: 458
Orange: 336
Red: 343
Light-grey: 38
Dark- grey: 346

TOTAL: 2806


Tan-lock: 42
Blue-clip: 23
Y-clips: 64
Silver-spacer: 292
Blue-spacer: 159
Track-splice clip: 1
Red gear: 20
Large yellow gear: 2
Yellow gear: 4
Blue gear: 13
Purple flexi-rod: 25
Orange flexi-rod: 13
Black rod: 4
Tan(red) rod: 8
Small tire: 5
Medium tire: 1
Large tire: 1
Balls: 3+
Chain links: 71

TOTAL: 749


Step 2: Base

The base is the start of all ball machines. It is also the start of most of the problems I faced when I was structuring the machine itself.
The last pic will explain why.

Step 3: Gear Mechanisms and Wheel Lift

This step includes all the gears for most of the machine as well as the wheel lift. This step may take you a while.

Step 4: Main Support, Lift, Motor and Drive-Shaft

Almost done with the mechanics!

Step 5: Chain-Transport System

 The main feature on the machine despite being there only for path 1.

Step 6: Secondary Supports and Path Selecters

Last long step before the paths!

Step 7: Path 1

The first path has the most interesting element on the machine, the single-ball block-gate.

Step 8: Path 2

This path uses Yardking42's Sidewinder element and martijnb95's Gap Element as well as his " Arm With Stop" element.

Step 9: Path 3

I would call this the lazy path because there is no major elements besides some super path.

Step 10: Path 4

The phoenix rises again! This uses my favorite element I used in two other ball machines as well as a wheel arm from Davinchi.

Step 11: Path 5

This path uses super path as well as martijnb95 Zigzag Stairs. There are ball alternators and a small chain path also.



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    31 Discussions


    5 years ago on Introduction

    I just spent £45 on extra k'nex so I can build this over christmas! It better be good ;) 

    You are absolutely one of my favourite ball machine builders!

    I like every machine you built. It's incredible, they're always sturdy and looking good. always cool new elements too. You also work very fast and you keep amaze me with clear, full instructions of the complete machine, every time again.

    And this machine proves it again!

    Congratulations for being feautured and good job! I voted! :D

    2 replies

    Thank you so very much for that comment! I'm just about ready to upload my largest ball machine on instructables. This will be my last one until the end of 2013 since I have to go back to college. Expect it in 1 to 2 weeks:D


    5 years ago on Introduction

    Great job, it must be hard to make instructions for such a dense machine. I like how everything is hooked up to one motor and that chain conveyor at the bottom. I also like the pun in the name. :-)

    4 replies
    zhamster rules

    5 years ago

    Wow I don't have anything stupid to say about this!!!!!!!!! I am amazed!:-)

    Sir "Speedy Gonzales" (you work so fast!) has once again proved his epicness! ;-) Absolutely amazing. You have surpassed my current expertise; keep it up! :-D


    2 years ago

    really good ball machine! this proves that you dont need a floor to make a good machine! it made me feel really confident about my upcoming ball machine, Journey. Thanks for sharing, good job!


    4 years ago on Introduction

    Are the red and yellow balls the same as the black and white balls? I only have the red and yellow ones?

    knex akbar

    4 years ago on Introduction

    nooo i have all the pieces except for just one large yellow gear!


    5 years ago on Introduction

    Hi, I'm having some problems with the balls going up the spiral lift. They keep falling off. did you experience this when building?

    1 reply