Instructables

The Official Guide for Building Knex Ball Machines

Featured
Hi! This is a collaboration between RNB, Shadowman39, and Tornado96.

This is our tutorial on how to make K'nex Ball Machines. It covers all parts of making and designing a ball machine, from the first sketches and ideas, to lifts, to the most advanced elements. Good luck with building yours, and post a picture of your ball machine!

Before starting, please take a look at these guides, to get an idea what you can do. Looking at ball machines from other users also helps a lot.
Enjoy! Feedback and/or suggestions for this guide are appreciated!
 
Remove these adsRemove these ads by Signing Up

Step 1: Planning

Picture of Planning
Before you start building, you have to get an idea. Some of you might think now, "I'm skipping this part, it's boring," but we really advise you not to do that! It helps a lot when you start with a good idea. It also helps construction to go quicker and easier. Before starting to plan, read through the ENTIRE guide. Each step gives tips about the desinging, how to make your ball machine sturdy, interesting and more!

Planning the ball machine
Before you're gonna draw a ball machine on graph or normal paper, you must think about the following:
  • Do you want a big or a small ball machine?
  • What lift(s) are you going to use? See this guide for all lifts!
  • Do you want 1 or multiple Networks? (a network is a group of lifts in succession, one after the other)
  • Are there elements that you absolutely want? (see the guides listed at the intro page for links!)
  • Invent new parts to make it original.
  • Will your ball machine have a certain theme? (see Step 2 for more.)
  • Plan a scheme that shows which path start at which network and at which one it ends: you don't want 3 separate machines, so there must be paths leading to other networks!
Planning the ball machine on paper
Now design the ball tower in your head, and write/draw some stuff down. The first thing you'll want to plan for a ball machine will be the main tower structure. These are the main towers that give the ball machine its height and mass. You don't have to plan all of the towers; just the main ones.

Make sure that the lifts fit in on they way that they have to fit in! If you have a small ball machine, we suggest having towers with blue rods as boxes, and yellow rods for diagonal support. If you want a big one, we suggest towers with red and gray rods, unless you have enough pieces to make a blue rod tower.

Now you're going to draw your ball machine on graph paper. You can also draw it on normal paper, but graph paper is neater. A rough sketch can be drawn on normal paper. We suggest taking 1 square for each blue rod. It's the most useful to draw it in top view.

You don't have to design all of it before you build. You can write it down on paper as you go. But it is best to plan at least the tower structure on paper. Planning tracks and elements on paper first can be hard, because the ball machine is 3D, and your paper is 2D. Even if you draw it from all sides, it can get hard. Drawing big elements first, such as Ferris wheels, is useful, so you know where you'll place the big elements. The same goes for lifts and networks of lifts. But that can be planned out after you've got the main tower structure down.
hi17 months ago
I find it easier to build the main lift (or lifts) first, and build the tower around the lift, then add other lifts.
Shadowman39 hi17 months ago
That's usually how I build them too.
dickheijboer8 months ago
I think it's better to build first all the networks and than the paths..
That's how I do it too, not sure why the order in the Ible came out different, since networks before paths is the more common way.
Yeah, but the persons who will use this guide don't build two networks I think..
mathsboy31410 months ago
I think it's worth mentioning different types of ball machines, such as freestanding, around the room, etc
The official guide to knex ball machine path separators:
http://www.instructables.com/id/The-official-guide-to-knex-ball-machine-path-separ/
I've added a link to the intro and step 6.
Fr-Pa-Co1 year ago
This is really useful but i still don't get the drawing part. Could you do a pic of some plans that you did.
www1391 year ago
Nice job
:D
mathsboy3142 years ago
Should I make a guide to path separators? I know and make quite alot of different ones.
I think that would be pretty cool.
Lego Andrew2 years ago
'Lame knex' means I didn't have alot & I was literaly POOR.
I think another thing you might want to add here is that making objects move will usually require another motor, unless you have tons of gears and a way of having them all connect in a way that doesn't interfere with your ball machine.
Yeah, me too. When I had lame knex, I tried to do something like that. Despite my geniusism, all i got was a rotating stick.
Lego Andrew2 years ago
I have asburgers (look it up,) and I already know what I'm gonna build! It means I can already see my ball machine in my mind (it's not easy: try it.)
sathothy2 years ago
Nice Guide. I am gonna try to plan the main towers for my next ballmachine. Do you have any pictures of an ballmachine on a paper?
KneXtreme2 years ago
DSC00752.JPG
Sorunome2 years ago
I never stick to any orders when I build my ball machines :D
RNB (author)  Sorunome2 years ago
Seeing Catastropha, you don't stick to any regular patterns in building! It is one big mess! (does not have to be bad)
Sorunome RNB2 years ago
Yeah, I know. I'm not that a planning guy......I just started because I wanted to, and now it truly IS one big mess and is very complicated to build the last two paths, as I can't really add support as it is surrounded nearly everywhere with track! :O
RNB (author)  Sorunome2 years ago
Learn to plan paths beforhand! Or just don't want to add that much of 'em! :P
Sorunome RNB2 years ago
Well, I HAD to add that many paths so there is equallacy in my ball machine.....I started out bad with the first two path seperators, one 3-way and one 4-way. I must have made a 12-way then for that, but instead i made a 6-way one and on some ways after that a 2-way one :)
My god thats complicated.. :) hows catastropha going?
Catastropha's good! Only two paths left till it's finished! :)
Tornado962 years ago
I find it funny how RNB has been the only one to answer posts so far! :P

Don't forget to be creative don't follow our instructions to the letter. :D
RNB (author)  Tornado962 years ago
lol. Sorunome is a good example :P
Sorunome RNB2 years ago
LOL! I literary laughed as I read that! :D
martijnb952 years ago
well done! you can add it to my contest for knex ball machines.
Sorunome2 years ago
Nice guys! :)
mikeasaurus2 years ago
Awesome job, guys! I hope there's more ball machines based on this information!
RNB (author)  mikeasaurus2 years ago
Exactly why we started this. We don't want the K'nex ball machine part of Ibles to die...