Introduction: How to Build a K'nex Ball Machine

About: I’m Hudson Shevy, an avid k’nex architect who loves building! I also spend a lot of time practicing the piano and drinking coffee. I have been building with k’nex for a long time and am getting more and more e…

Wondering how to build a k’nex ball machine? Then this is the instructable for you. In this instructable I will go through the 6 steps of building a k’nex ball machine and give some helpful tips along the way as well.

Step 1: Buy K'nex

The first and most obvious step of building a ball machine is buying K’nex. You can buy them on Amazon and Target, but I suggest buying them on Ebay (link to my ebay account), Mercari, or various other thrift stores. They are significantly cheaper. I suggest to buy bulk lots rather than specific sets, because you can get a lot better deals that way. With the k’nex from the bulk lots, you can then find instructions online and build bigger and better things and save a few bucks. If you’re looking for a really good deal, I suggest searching for the most recently listed items, so you can find a deal before someone else does. Also generally don’t buy from popular k’nex ebay stores, as they will charge you almost as much as Amazon. Since K’nex are getting less and less popular, chances are they will keep getting cheaper and cheaper, until sellers are just trying to get rid of them. This is great for buyers, because while most things are raising in price, k'nex prices will be lower.

Step 2: Design the Structure

The first thing I suggest building is the structure. It’s good to have a unique structure, so your ball machine looks cool. Make sure to build the structure as high as you can, based on the k’nex you have. The hardest part about the structure is making sure that even while being tall, it is heavier at the bottom and has a good support system, so it doesn’t just fall over. I learned this the hard way, with my first ball machine, Alpha. I was new to building machines and didn’t understand the support that was necessary. The entire machine fell over several times and took a very long time to repair. Since then, I have always made sure to have a strong structure. While this step isn’t a whole lot of fun necessarily, try to be creative and enjoy it. The structure pictured is the one I used for my ball machine, The Two Towers.

Step 3: Create the Lift

The next step is probably the hardest, and that is making the lift. Lifts are hard to create and even harder to perfect. While I usually do the classic chain lift, as it is the easiest, it is much cooler if you can use a different lift instead. If you don’t want to come up with something, however, there is a guide that has many different ideas of lifts here. Lifts always require a motor, and have to somehow bring the ball from the bottom of the machine to the top. Some different types of lifts include helix lifts, chain lifts, and wheel lifts (pictured). Overall, the hardest part of a lift is making sure that the lift can actually reach the top of the ball machine. If you are using a heavy wheel lift, you have to somehow support it so it doesn’t fall and that can be very difficult.

Step 4: Make the Elements

Now for the fun step! This step requires a lot of creativity, and is very time consuming. All your elements should be very different from one another, so people don’t get bored watching them. I suggest building them as you go, so that you don’t feel forced to fit one in somewhere but rather are building the element specifically for the path. Elements can be anything from wheels to stairs to loops! They are the true test of a k’nex creator’s skill. The bigger you build them, the cooler they will look and the more they will add to the machine. Pictured are 6 elements from my previous ball machine, The Two Towers, with a video here.

Step 5: Test!

After everything is put together, test, test, and test again! Don’t just assume that the machine will work (because it won’t!). It’s a good idea to this while you build along the way, because otherwise you will have a lot of problems on your hands. Have all the balls run through the paths for up to 30 minutes. You need to make sure the ball machine has a very low probability of failure which helps with the videoing process and makes it cooler when showing your machine to other people. This step is extremely important and tests the creators self-control and perseverance. While it can be frustrating, you need to stick at it until it is perfect (or nearly).

Step 6: Make a Video

The final step is to make a video! Rather than just videoing the whole thing from a distance, you should video different paths from different angles. That way, you can watch your video later and rebuild elements or just look at how you have improved in your building. You can video with a phone, but I suggest using a camera as it is generally much easier to get good videos. It is key that your video is high quality and put together well. If you want to check out my videos, visit Hudson's K'nex Productions.

Step 7: You're Done!

Thanks for reading, make sure to leave a comment below and check out my other instructables!