While using Bittorrent Sync on my Raspberry Pi, I had some issues with BTSync using too much RAM. To solve this problem I decided to create a 2GB (count=2097152) swap file and see how it would perform. To do this follow these steps:
Create a swap file in your filesystem replace “/PATH/FILENAME” and “SWAP_SIZE” with desired values. “SWAP_SIZE” is in kilobytes:
the “dd” command can take up to 5 minutes, depending on how big “SWAP_SIZE” is.
After we finalized our plans and all the stuff we bought online slowly made its way from China to Switzerland, we could start assembling the tower. We started by constructing the frame.
The Frame is made of 4 aluminum bars on each corner. They are held together by threaded rods, nuts and bolts.
The first step is to drill holes into the aluminum bars. In the end The Acryl Glass will sit on the threaded rod and will create a “level”. So we had to think and calculate the distances between the holes. We also took into account of how high a Raspberry Pi v1 and v2 is.
As you have seen on our plan, we chose to have 4 “levels”. They are made of 5mm acryl glass.
The cutting plans with and without holes can be downloaded here:
The “levels” where the Raspberry Pis sit should also have some kind of drawer mechanism, so that we can pull the Pi holder out easily. This is made with the curtain rails we bought from a local store. The holes in the cutting plans serve as screw holes.
Raspberry Pi holder
The Raspberry Pi holder is a piece of acryl glass where the Raspberry Pi is mounted. We made plans to cut holes for a Raspberry Pi, but you can adjust them to mount a 2.5″ hard drive for example.
Before building the tower we had to organise and buy some material. Here is a shopping list which can be used as an example to build the tower. As mentioned before, we could use some really great tools like the laser cutter and professional drilling tolls from the FabLab Bern. If you don’t have access to such tools a short search on Google will probably help (like how to cut Acryl Glass).
I would say that the concept is the most important part of all! If you forget to think about the details, the cost will be higher, you will be wasting more time or your project will be useless. So, be aware! But keep in mind that “a simple concept is usually the better one”! Don’t do over-engineering!
We have drawn 2-3 concepts before we were convinced we got the one which could be our best shot. To get some inspiration, we searched the Internet for some other Raspberry Pi Tower projects. We were happily surprised that the official Raspberry Pi forum is full of amateur projects and ideas. Our concept was inspired great ideas and mistakes of other projects.
Let list some properties we want for this tower:
Medium size (even if it is suggestive what medium means)
Maximum 200$ with 4 RPis
Can be easily carried from place to place (it would be nice if we could take our prototype home…)
Can be prepared and assembled in less than one day
Draw the concept
In a logical way, we should draw the concept before going to the online-shop and buy thousands of things we won’t need. Here are the drafts we made.
Pro / Cons: – Waste of space (only a few RPis can be placed on each level) – Cable management: the RPis are not near to each other – A fifth additional RPi would need a new level + Modularity: Each level can be swapped and they are similar
Pro / Cons: – Scalability: the height of each RPi stack is very limited – Cable management
– Access to each module – Stack stability + Modularity
+ Space management
Pro / Cons: + Modularity + Extensibility + Scalable + Cable management + Easy access to each module
+ Space management
+ Each blade can contain a RPi, HD, SSD, Arduino, … – Each RPi has to be mounted on a blade
Tobias Fiechter and I (Philippe Wanner) have worked together on an embedded project at the FabLab-Bern. There was a laser cutter and some professional power tools to turn any good idea into a working prototype.
Lucky us, after asking for a crash course how to handle these tools, we thought what could we build that would make our lab at home more professional, clean and proper. That’s how our Raspberry Pi Tower project was born.
You could ask yourself why would I need a Tower for some tiny raspberry Pis. Here are some self-explaining reasons:
You don’t have an extra room for a lab server.
You don’t want something noisy and your electric bill is already too high.
You have a tiny budget or you want to spend your money for a brand new car.
You love to build something on your own.
We are technology enthusiasts and love to learn by doing great things! Which also means we sometimes have to build some prototypes before it can go into production. This project is our first prototype, please be indulgent.