In keeping with the “It’s too damn hot to hike but I need to type something” theme:
I started thinking of some new raspberry pi projects, since my lightshow is about done. One of the things I kept seeing online was people making their own custom cases. For the most part, they were variations of the standard black or clear mini case, the ones just big enough to fit the Pi inside. Someone had constructed a really cool wooden one, but again it was just a variation on a theme – a very small case for a very small computer. I was thinking about that, but then started going in the opposite direction. What about something over-the-top crazy? Like something big and beefy and over-engineered… Extra lights, a big fan (since I already installed a little 40mm fan in one of my Pi cases), and maybe some weird options that didn’t make sense.
But what could I put it in?
Then I ran across this:
“This” was an old 650watt power supply case from before I did some computer upgrades. It had all the standard cords sticking out, and was crammed with internal guts. I was taking the cool lighted fan out to save it, but decided to keep the box and just chuck the guts in the trash. The box is actually quite nice looking, the photo doesn’t do it justice. Its a nicely smooth polished metal, probably stainless steel, definitely not aluminum. It cleaned up nicely; I carefully scraped off stickers and used Goo Gone on the glue, and the box looks pristine and unblemished.
The first thing I did after cleaning it, was to open it up and gut the insides. I left two parts:
The first was the aforementioned fan. Its about 6 inches wide, or 140mm. It is clear blue plastic, with four corner blue LED lights that glow while it’s running.
The second thing I kept was the cluster of wire bits directly soldered to the outlet where you plug in the wall cord. There is a switch attached to it, and what looks like an inductor and a few other bits. But, whatever its function, you put 120v in, and you get 120v out. There are two brown wires in the top of the picture, part of a separate switch. Normally it is part of the selector for switching the power supply from 120 to 240 volts for European use. This switch will eventually be the fan controller instead. There might be times when I don’t want a hurricane force wind blowing across the desktop, and I can switch it off.
After gutting, I started trying to decide how to lay stuff out. Initially my goal was to have the ports sticking out the back, just like they are on every other RasPi case, everywhere, and the HDMI and headphone plug on the side. That’s when I realized it would take a heck of a lot of complex metal cutting, and with the tools I have and my skills, I knew I just just screw it up big time. Plus, the damn HDMI monitor cables are a pain in the ass to deal with, and either I would have to cut more matching holes in the side of the case, Or have a cable sticking out all the time.
Also, I needed room for two small power supplies. The first provides 12 volts to run the fan, since most computer fans run off the 12 volt rail. The second provides 5 volts for the RasPi, since it runs off 5 volts.
It was soon evident I would have to take a new approach. Instead of having to open the case every time I wanted to plug or unplug the RasPi from a monitor or headphones, I would put the HDMI and Audio port on the back, and leave the others inside the case. The RasPi has WiFi capabilities, so although it has an ethernet port, I don’t use it that often. It also has 4 USB ports, one which I plug the remote keyboard/mouse thing into, and the others largely go unused. I did add a flash drive to it, but that’s about it. So after gouging at it like a drunken caveman with a stick, I was able to cut to small port holes and drill out the headphone jack area.
Wait, you say. The Raspberry Pi needs power, and I have the power jack sticking out the back of the box next to the HDMI port. How is that going to help? Two things: In the event I just want to run the pi without all the excess stuff, I can just plug in a USB battery pack. The second thing is, the RasPi comes with a lot of “test pads” and solder points on the bottom of the board. Two of them let you power the board without plugging anything into it. So the white and yellow wires under the board below will connect to the power supply next to the Pi.
WAIT! you say. Everything’s going to short out and blow up! Okay, right now the Raspberry Pi is on little plastic standoff feet. Although it looks like it’s on the metal, its not. Tow of the feet even go all the way through the bottom of the case, and lock it into place. Thanks to the headphone jack, you can’t lift the other side of the Pi up, so it is pretty solid. Unfortunately, those are all the mounting holes I have.
The power supplies, which are the insides of those oversized wall plugs, have no mounting points. Since they were just slotted into plastic housings, they had no need for mounting holes. BUT – I can glue the standoff feet to the bottom of them, and then hot glue the plastic feet to the case. They are close to their final positions now, but I have to do some rewiring first.
If you look really carefully you can see where I cut off the brown wires in the top right, and replaced it with the fan’s jack. This jack will let me completely remove the top of the box to work on the insides.
One thing I’m not sure what to do with yet. The power supply had a pushbutton switch on the back with 3 LEDs in a column, and its purpose was to let you select three fan speeds. Blue was auto-controlled, the power supply decided if it needed the fan at all, and would shut it off if it was cool enough. Green was a low speed continuous running, unless it decided it needed more. Red was a bypass mode, the fan ran on high all the time.
So I have a pushbutton switch, which is just a momentary contact switch (much like the “pulse” mode on a blender or coffee grinder), and three LED lights. I’m not sure what to do with them, but I’m thinking about wiring up one of the LEDs as a on/off power indicator.