Could I really class myself as an engineering student if I wasn't madly over obsessed with the droids from Star Wars? Of course I couldn't. So when the remote controlled BB8 was released I knew I had to buy one straight away. But then I realised I was a student. A very poor student. What is the only thing you can do if you can't afford something you want? Make a cheap knock-off of course! The premis for this project is that all amterials required can be gathered for less than £20, but the truth is if as long as you dont live in a 4x2m room such as myself, you can probably find everything you need lying about your house. In which case you can get your very own remote control BB8 not only for free, but you can use up some of the trash about the place.
The idea for this project came to me the same way most of my idea's do, whilst stumbling home drunk at 4am after another student clubbing experience. Fortunately one of my flatmates was on hand for me to yell some things at to write down and text me so I would remember in the morning. Hence the cheap remote control BB8 was born.
Now I should state that for the price this project costs, you cannot expect an incredible replica of the original, in scale or in ability. I should say however is you have a larger budget to spend than I, you can make some minor changes throughout this build that will make your droid a lot more realistic.
Step 1: The Body
To start this build, we are to build the body of BB8 along with the driving mechanism. Saying that I think saying that I will build the driving mechanism is a bit of an exaggeration, what I shall really be doing is stripping and hacking away at a remote control car.
What you shall need:
- If you are yet to deduce from the previous paragraph that you will need a remote control car, then YOU WILL NEED A REMOTE CONTROL CAR. I bought a very small, cheap RC car for £9.99 from the local toy store. When it comes to trying to choose a car for this project it is important you follow these very intricate guide lines. 1) Is it a remote control car? 2) Does it work? If your RC car has passed everything on this tedious checklist, then you're good to go.
- Next up you will need to find yourself a hollow sphere. Now I went for a fillable ball ornament decoration for a Christmas tree. I would recommend that whatever you choose as your body, make sure it is acrylic as this really is the perfect material. Keep a close eye on the dimensions of the ball you pick so that it is not significantly larger or smaller than your car. For example my ball ornament had a diameter of 100mm, and the RC car, before I started hacking at it, had a length of about 110mm.
Those really are the only components that are needed to create this body. I would also recommend a box cutter knife and some sand paper for the actual construction.
The first order of business is to unscrew the chassis, and any other non-essential add-on's. Once I had completed this step I took a series of pictures and made a number of sketched on the driving mechanisms of the car so that if any mistakes were made I would easily be able to reconstruct them. This is not essential of course.
As I am sure you can work out from the measurements stated earlier. The car was not able to fit into the ball at this point. So I did the only thing I could, I grabbed a box cutter and went to town. After hacking off all non-essential plastic, I was left with what can only be described as the stripped carcass of what was once a Bugatti Veyron, the car was able to fit into the ball quite comfortably.
Now its sand paper time. In order for the tires to get enough grip on the inside of the ball, the inside needs to be as scratched as possible. If you went for the fillable ornament like I do, you should also take this opportunity to remove the loop on top of the ball. I used a box cutter knife, but I would advise using literally anything else as this took me an age.
I feel like I have glossed over what was actually quite a long and tedious process, so if you find yourself having any problems by this point then please let me know and I'll be more than happy to help out.
Step 2: The Head
Before we can start work on the magnets system as a whole, we need to make the head. Parts needed for the head:
- Ping Pong Ball (6 for £0.99)
- Felt tip pens/ any material you need to use to create the design of the head (4 markers for £0.50)
- Magnet (I used a small metal screw)
Ideally for the head I would use half of a smaller acrylic ball, however not only are these excruciatingly hard to find on the cheap, but it would also probably prove too heavy. Although forgetting the fact that the proportions are off using this method, a ping pong ball will be just fine.
The first step is to cut the ping pong ball in half. You can use scissors, box cutters, whatever is easiest for you. I drew a circle with the same diameter as the half of the ping pong ball on a piece of cardboard and cut it out. This fit in quite snugly.
I took a compass to the centre of the cardboard circle and pushed a small hole. Then with a pencil, I made the hole big enough for the screw to go in. After I was confident that the hole was the correct size, I glued it into the head.
So that's it for the construction of the head, from here its all on you for finishing it. As stated earlier I used felt tips along with the aid of a compass to create the design of my head.
Step 3: The Magnet System
Its time now to move onto the really cool part of the build, the part that really makes BB8 stand out. Its time to make the head float.
You will need:
- Corrugated cardboard (Cut some from old packaging)
- 5 toothpicks (100 for £0.49)
- Magnet (I used a SF19V from Maplins - £1.89)
- Something heavy to use as a counterweight
And that is it, we have now covered everything you will need to make this project.
You want to start off by getting an idea of the distance from the top of the car to the top of the ball. Trying to get the height of the structure here is by far the most difficult and tedious part of the project. I'm warning you know, prepare to get very frustrated.
I started off by cutting out two rectangles of the cardboard, just smaller than the RC car and glued one on top of the other. Taking the 5 toothpicks, I pushed them into the cardboard in such a way as to ensure that the magnet could be held in the air by the 5 of them. Using tape, I attached this system to the top of the car. Placing the car back into the body, I tried to attach the other half to get an idea of how much of the tooth picks I needed to take off to get it to fit inside. My next step was to trim the tops of the toothpicks so that they could fit inside the body.
Now to the truly frustrating part, trying to get the height of the magnet right. If the magnet held by the toothpicks is too far away from the magnet in the head, the head will fall off. If its too close, then they will clamp together meaning that the body cannot role. After about two hours of adjustment I finally managed to get this just right, but obviously the required height of the magnet will vary massively depending on the strength of the magnets you decide to use. Once the height was decided I wrapped tape around the toothpicks to ensure they keep their shape.
Now attach the counterweights to the bottom of the RC car, obviously make sure that they wont prevent the wheels from touching the sides.
Step 4: Finishing Touches
So now that the general construction is done, its finally time to put the finishing touches.
For me the finishing touches involved:
- Smoothing off the head, making sure that the cut is straight
- Ensure that where I cut off the hanging ball loop on the body is sufficiently sanded down
- The magnet support structure is properly glued and stuck down, basically making sure nothing will fall apart whilst it is running.
As I'm sure you have probably noticed by now, the body has no cover!? It is still just its ugly, sanded down acrylic shell? Well the reason is I am illiterate when it comes to photo-shop, and as I was unable to find any BB8 stencils online I was unable to create the body cover. If however anyone reading this would be willing to create the stencil please let me know and I will add it to this project with the appropriate credit etc.
Step 5: Finished!
So there you have it, your very own remote control BB8 droid, and this project came to a total of just under £18. What a bargain if I don't say so myself.
Now don't get me wrong, this is by no means the most technologically advanced project out there, nor can you expect Disney to be getting in touch about renting it for the next star wars, but it is a good place to start and most importantly a lot of fun.
Footage of this thing in action is at the beginning of the instructable. I am currently editing the video walk through of this project for YouTube, and as soon as it is live I will embed it here as well for all to see. In the mean time, I hope you found this article enjoyable if nothing else. If you decide to replicate this project, or can think of any improvements then let me know! I would love to see any other versions that are made.