Introduction: Ion Cooled System for Your Raspberry Pi Game Server!
A while back I got Raspberry Pi, but I didn’t really know what to do with it. Recently, Minecraft has come back into popularity, so I decided to set up a Minecraft server for me and my friends to enjoy.
Well, it turned out to just be me : /. Anyway, now I need a quite serious cooler which can cool the server...
So in this Instructable, I will show you how to make a pretty badass one. It will include a water-cooled loop, with no moving parts, as the radiator will be cooled by an optional ion fan. Now, I do admit that I equally focused on the design as on the functionality. For the installation of the server itself, there are numerous tutorials online. I followed this video. If you want to enable others to play, you will also need to port-forward your router, there exists plenty of information for this online. Anyway, let’s get making with the cooler system!
0.7 mm sheet of copper or aluminum
4 mm and
6 mm copper, brass or aluminum pipes¨
3D printing filament (and a printer!)
Some 22 gauge copper wire
A high-voltage AC-transformator (can be found on various sites online, please Handle with Care!)
2x 5-volt wall adapters (one with a micro USB connector, the other just with bare wires)
4x motherboard chassis adapters.
An adhesive (preferably silicone)
A soldering iron with solder
And wait! I forgot the Raspberry Pi!!
Step 1: Choice of Materials
Before we rush into the making of it, I needed to find a build material with the right properties, which turned out to be copper. It has a similar thermal properties to silver which is the best heat conducting metal. This is important, as we want to transfer the heat from the CPU and other ICs to the liquid, and then out into the air effectively. Copper is quite expensive, however, it was crucial for this project. If you want to find an alternative, aluminum would be one, as it also conducts heat well. This sheet of 0.7 mm copper cost me around $30 but aluminum would be far cheaper than that. I will make the cooler block modules out of the sheet and I will connect the different modules with 4 mm brass and copper tubing, but of course you could just as easily use aluminum or plastic tubing for this purpose.
You will also need some kind of adhesive to connect all your parts. My immediate choice was just to solder everything together. However, in this instance, the thermal properties of copper are actually worked against me, because as soon as I wanted to solder to parts together, all the connections next to it started melting. So I looked for other alternatives, more on that in the “quick” notes below.
Step 2: Some Quick Notes
As an alternative to soldering, I tried a 5-minute quick epoxy, a synthetic metal compound, and CA glue (super glue). The epoxy didn’t really bond, the synthetic metal never cured and the super glue seemed to work fine, and only showed its flaw after a few weeks, when the copper started to corrode and the glue crumbled to its demise. The dried glue was reacting somehow, I’m not sure if it’s the water, aluminum or the baking soda which I used as an activator that causes this, although the same happened near the copper. The result was that after the glue started crumbling, all the water leaked out. If someone knows the answer to what caused this, I would love to know. Finally, I had to disassemble the system, and reassemble everything with silicone. I hope this will finally work, as silicone is much less reactive (but only time will tell).
Much of the footage was never re-recorded, so just so you know, in all the pictures that you see me apply super glue, you should instead use silicone.
Another note is that while I state above that I used sheet copper, I used aluminum for the radiator block. It is much larger, and gets less warm, so the cheaper aluminum will work just fine.
In terms of transformers, I did try using a $15 Neon Transformer, but I didn't get it to work unfortunately. What did work was the cheap 3-buck-or-so cheapo step-up transformers. Most of these, such as this one have an operating voltage of 3.6 to 6 volts, which is perfect for our application. The output voltage is around 400 000 volts, so please be careful when handling, and do not get too close to it while operating. Furthermore, when handling after operation, please discharge the transformer by shorting the output leads with a screwdriver or such.
Step 3: Cutting&Bending the Sheets and Sealing the Blocks
I started by designing the cooler blocks. You can find the design templates for everything, both the blocks but also the tube dimensions, as attachments. These designs are for the Raspberry Pi 3 model B, however I think they should also be compatible with the B+, as the two only differ in the raised metal CPU casing in terms of form factor (at least for the parts we care about). If you’d like to make this for the new Raspberry Pi 4, you’ll have to design the system on your own but don’t worry, it’s not that difficult.
Anyway, I printed out the templates and attached them to the copper and aluminum with double-sided tape. I cut out all the parts with metal scissors. A Dremel tool can of course also be used, but I find the scissors are a far quicker method (less noisy, too!). After that, I bent the sides. I used a vice for this, but avoided needle-nose pliers, and instead used a pair of flat-nose pliers (I don’t really know its name) where the vice wasn't viable. This way, the bends will be straighter, and more defined. After all the bends were made, I removed the template.
Inside the cooler blocks, I secured a few pieces of metal, angled upwards (when they are mounted in place). Now, the theory behind this is that the cold water will come in through the sides, and "get caught" in the shelves of metal, cool the CPU and then rise and exit through the top pipe, though I don't really know how to analyze if this actually works. I would probably need a thermal imaging camera to see if the theorized path of the warm water actually is the same in practice.
When it came to the heat sink block’s heat disposal area, I wanted to bend it in a wavy fashion, to maximize its surface area. I tried to score and bend, but this turned out to be a disaster, as at least half of the bends snapped. I tried to glue all the pieces together with CA, but as we all know, this also failed miserably. It worked fine with silicone, but if I were to do this again, I would use something like a thicker foil, and I would also make the bends in the other direction, so the warm water can flow in the channels with more ease.
Next, when all the bends were made, I sealed all the gaps with silicone, from inside.
I also made a grid out of 8 pieces of aluminum. I used an interlocking technique to connect them to eachother, along with silicone. I'm not so sure why I decided to make this, I guess my thought was that this way the warm water coming sideways wont sink down to the inlet pipes, but the sinking cold water, from above would. In retrospect, the idea seems quite far-fetched to say the least.
Step 4: Printing the Stand and Some Bad Decisions....
I 3D printed a stand, both for the Pi and the radiator block. I assembled all the parts, which you can find as STL attachments. This helped me out with the cutting and bending of the tubes, although this won't be necessary for you, as I have also provided a template for the bending. I spray painted it silver, but this was the stupidest decision. You see, in spite of the good looks, it isn’t really practical, as it contains metal powder. This makes the paint somewhat conductive, which is bad if you want to use it as a stand for high-voltage electronics (long story short, it started to smell burnt plastic). I had to print out another holder for the copper pins of the ion fan, which although is printed in silver, doesn’t conduct electricity. Now, let’s move onto the tubes.
Step 5: Cutting&Bending and Connecting the Pipes
I cut the sections of pipe a little bit longer than needed, just to be on the safe side. When it comes to the bending, you can of course use a pipe bending tool, but as I don’t have one, I utilized a free method instead. I took a piece of cardboard, and glued it to one end, and filled up the tube with sand. The sand will even out the stress and minimize the creases in the metal. For the bending, it’s easiest to use something like a clothes rack or a curtain rod. I made sure to constantly check to be sure that everything will fit, and also assembled some pieces as I went. As a reference, you can use the template attached.
I made some necessary cuts with a multi-tool. Where the pipes will connect on both sides to the cooler blocks, half of the pipe was removed. I used silicone to connect these pipes. Now, originally I was going to have 3 cooler blocks, but I decided to not bother with the one for the memory, as it was on the back side, and removing the Raspberry Pi would be difficult with it being clamped together from both sides. Besides, the main generator of heat is the CPU (though, I don’t really know why the Ethernet processor would need cooling, maybe because it looks so cool?). I ended up just sticking a heat sink on the back side, and covered up the holes of the radiator with metal plates.
I also made two 6mm holes in the top of the radiator block, and secured two lengths of 6mm pipe. These will work as fill and drain pipes, but will also release some of the pressure as the water heats up.
Lastly, I secured the top of the radiator with silicone.
Step 6: The System Takes Shape...
I mounted the Raspberry Pi temporarily, to be sure everything was aligned. I used soldering to connect some pipes, though the rest was done with silicone, and held the parts in place with tack, until the glue had dried. When securing everything, be sure to not get silicone onto the back side of the cooler blocks (which will connect to the ICs) as well as into any pipes.
After everything had dried, I wanted to see if the system was waterproof. This can be done by submerging everything under water, in a bucket for example (with the Raspberry Pi removed, obviously). With the help of a straw I blew air into one of the drain pipes, and blocked the other with my thumb. Where bubbles emerge, there is a hole and I applied more silicone there. This was repeated until there were no more bubbles.
For extra protection, I applied transparent nail polish to the Raspberry and to all of its components, to act as some waterproofing.
Step 7: The Tale of the Ion Fan
There certainly exist better and faster methods to make an ion fan, the easiest is just to take two metal mesh pieces and connecting a few thousand volt high voltage source to both. The ions will go from the mesh connected to the positive wire and fly toward the negatively charged grid, and at last they will exit through it and continue flying, thus giving us the slight wind (Newton’s Third Law). This approach would have saved me many hours later on, but still, I consider my own approach (Makezine style) waaaay cooler (See what I did there, with the word “cool”? Nevermind).
I started by cutting up 85x 5mm lengths of 6mm brass pipe, for the negative grid. I grouped them together, 7 by 7, in a honeycomb-shape. I used aluminum tape to hold them together while I fixed them in place. Here, I couldn't get away from soldering, as it is the only method I had that could connect the pieces and also conduct electricity. So each time I soldered together larger chunks (not the ones in Minecraft though), I had to tape everything so that nothing would fall apart. I used a buthane torch instead of an iron to connect these hexagons together, and also added a few smaller pieces to get to the right shape. I connected a wire and sanded the side facing the positive grid flat, as all the pipes should be equally far from the positive grid.
Speaking of the positive grid, that was equally hard to make. I printed out the grid, which can be found as an attachment. I cut 85 ppieces off 22 gauge uninsulated copper wire of equal length. To prevent the print from melting, I soldered eveything together while the plastic was under water. Each of the 85 pins (let's call them "probes", sounds much cooler) were pushed through the holes, and the probes were connected to longer pieces of wire from the top. These were in turn soldered to a wire which will later connect to the transformer. While soldering, make sure all the probes stick down equally , I used a piece of plastic to make sure of this. The more precise, the better! I applied a drop of glue to each of the probes, to secure them to the print.
Before securing the two grids with glue, I tested the fan with my power supply and transformer. The system shouldn't arc, but it should produce a sensable stream of air in through the negative grid (if you feel it on the positive side, you may have connected the output wires of the transformer the other way around). It can be hard to find this sweet spot, but when you got it, secure the brass pipes to the plastic with glue.
Step 8: Electrical Work and Setting Up Everything
I secured the Ion Fan to the top with silicone making sure that its metal parts are far away from the rest of the system. I also fixed the high-voltage transformer to the back side with silicone and connected the corresponding output wires to the copper wires from the positive and negative grid, making sure there is a fair bit of distance between these (the last thing I want is arcing). I then took my power supply with the bare wires and connected the wires with the input ones of the transformer. Be sure to add insulation.
Next, I added thermal paste to the back side of the cooler blocks and mounted the Raspberry with the 4 motherboard standoffs.
I added water into the system with a pipette, and made sure to shake the system (the last thing we want is an air bubble trapped in one of the cooling blocks). When it was nearly filled up, I slightly tilted the system to get rid of the air trapped between the radiator fins.
It is finally finished!
Step 9: The End
After all this, the Ion Cooler is finally finished! I plugged in the Ethernet, Power and Fan connector and powered up everything. Now it is apparent that the system isn't perfect. The radiator fins are covered in silicone equally as much as not, so I question it's funtionality. Although, much of the heat disperses anyway, through the tubes and cooling blocks. I would say that the Ion Fan is better than nothing, but not as good as a mechanical one. Though, there you have the drawback of noise and lifetime. My measurement of its power usage got a value of 0.52 A at 5 Volts DC. Although the output voltage is much higher, it could potentially hurt you, so be careful!
The really sad thing is that, while I built it for me and my friends to enjoy, they have now gotten tired of playing Minecraft....
Anyway, above you can find a gameplay video, if you are interested.
I hope you liked this project, if you did, like the Instructable and consider voting for me in the competition :).
I'll see you at the next Instructable!
Participated in the
Raspberry Pi Contest 2020