As I'm sure many of you know the Raspberry Pi launched a few weeks ago (www.raspberrypi.org). As the initial units will ship without a case I decided to make one.
The case was modelled using Pro Engineer CAD software and then rapid prototyped by a company in the UK (more about that later).
One disclaimer before we start - I'm currently on the huge waiting list to get a raspberry pi so this case has been designed around the official dimensions for the device. Until I get my hands on one of the units I'm unable to guarantee it will actually fit.
Step 1: What is the Raspberry Pi?
"The Raspberry Pi is a credit-card sized computer that plugs into your TV and a keyboard. Itís a capable little PC which can be used for many of the things that your desktop PC does, like spreadsheets, word-processing and games. It also plays high-definition video. We want to see it being used by kids all over the world to learn programming."
- source - The Raspberry Pi Foundation - www.raspberrypi.org/faqs
Step 2: Get the CAD files
It took quite a lot of modelling in CAD to get the case looking the way I wanted.
The files were exported in the STL format. I'll go out on a limb and say 99% of 3D / rapid prototyping machines will work with this file format.
The STL files can be downloaded from the 123D gallery:
Alternatively they can be downloaded directly from this instructable
case_lower2.stl841 KB case_upper2.stl
Step 3: 3D Printing
Many members of this site will know far more about 3D printing and rapid prototyping than I do, but here's a brief overview of your options to get this case printed:
Homebrew printer - There are a number of kits available which allow you to build your own 3D printer - such as the makerbot (http://www.makerbot.com/). I'm sure there are also a few instructables out there that also show you how to make your own 3D printer from scratch. Making a printer, even from a kit, is a very time consuming and potentially complicated process so building one is not for the faint of heart. Once you have your own printer though, you can print pretty much anything - including the parts from this instructable!
Online service - there are a few companies which now offer a service where you can upload your own model, they will then print your model and post it back to you. Shapeways is one such company (www.shapeways.com). As you'd expect the cost per model is a lot higher than using your own printer, but if you only plan to print a few models a year then this could be the option for you.
Bespoke order - Lots of rapid prototyping companies exist, both in the UK and around the world. It may be possible to get your parts printed by them.
As I do a lot of rapid prorotyping as part of my Job, I already had a contact for getting this part made. I used a company in the UK called CRDM (www.crdm.co.uk) and the part was printed using a "HP Designjet color 3D printer" (www.hp.com/go/designjet3D).
Overall I was very impressed with the results.
Step 4: Model finishing
The two parts of the case fit together by locating the six pins in the 'lid' part into the six holes in the 'base' part.
As with any type of prototyping, there is bound to be something you haven't thought of. In my case it was not taking the material shrinkage into account.
It was necessary to open up the 6 mounting hole using a dremmel. I used a 2.5mm drill bit to make these holes a little oversized.
Step 5: Conclusions
Overall I'm very happy with my case.
Once I have my Raspberry Pi, I will test that it fits inside the case - If modifications are required I will update the CAD and this instructable (I'll also probably fix the problem with the undersized holes).
For now this case is going to have to sit on my desk and look pretty, while I patently await the delivery of my raspberry pi board.
I've also entered this instructable into the Make it Real Challenge (http://www.instructables.com/contest/makeitreal/) So please vote if you liked this instructable.