“Make an external watercooling system that is compact and also self-priming” – Owen Stevens
This isn’t my follow up article on Jet Coolers, sorry! But I hope you like it just the same.
Every time I create a new water block, mounting it for testing is a pain in the neck. I decided to make a very radical change, I went case-less!
It all started with the “new” Hydor L30 I won as a prize from Overclockers.com. My existing pump is a epoxy covered mess and I new could put this new one to good use. Here is the old one, yuck!
The new pump is much better to look at! Thanks Overclockers.com!
What I decided to do was make an external watercooling system that would be compact and also self-priming (Phase Two). This way I could change out water blocks with minimal muss and fuss. I also wanted to have a nice, simple system setup that was similar to the Senfu Tech station (Phase One).
The first step was to convert my existing system. Below is a composite pic of the old setup, quite large and freakin’ heavy to move. It is a 12 bay full tower with water cooling stuff, two hard disk drives, floppy, a tape drive and right now only one CDRW. I am guessing around 50lbs. Which is lighter than the 80lb bags of rock salt I carry down to the basement to put in my water softener. (Good thing I’m not a “pencil neck geek”, just a “computer nerd” as one friend put it. 🙂
I have a spare motherboard (mobo) left over from my lightning experience so I started with that.
Here is the scrap wood I started with. I make furniture occasionally so I have some scrap plywood and planks lying around. (It is no that I have a competing hobby with overclocking. I just like making things and everybody needs furniture, right!)
The largest board is a spare “wooden shelf” left over from years ago that just so happens to be the exact same width as my motherboard! (Actually, the shelf board was made of a high density particle board covered with a real wood veneer. I didn’t find that out until I sawed into it. It’s left over from my mother’s house so it could be from the 1970’s for all I know.)
I measured it with the motherboard for length …
… stuck it in my vise …
… and cut it in two …
… with my new saw!
I didn’t get any pics of that cutting operation but you can see the board underneath the mobo in this pic of me testing the card clearance. (You can see one of my favorite tools setting next to the mobo on my bench.)
A back side shot of the mobo on the board.
(A side note: I was trying to get my old dead ATI Expert 2000 card into this dead NF7-S but the damn AGP slot has a plastic bit in the way so the card wouldn’t seat right! Some mumbo jumbo about AGP 1X verses 2X or something. I fixed that with a chisel and my favorite tool, a hammer!)
No more divider (or locking tab for that matter — it fell off) …
… and the card seats fine!
Don’t try that at home, or you’ll end up where I started: two dead components! :
Any way, to mount the mobo to the wood I first tried marking through the holes with a marker, but that was not very accurate.
So I decided on an alternate method; using stand off screws like these.
I attached them to the mobo like so. This pic also shows the marker “blotches” that didn’t’ work too well.
Here’s a close up of a screw in the mobo:
To make the marks I simply laid the mobo on the board put a screw driver on the screw head and whacked the screwdriver with a hammer!
This made nice little dimples:
Next, I used a 7/64 drill bit, sized here –
– to make a hole for the screw to set in, as shown here:
I repeated this for all of the dimples, inserted the stand offs, and added some wood glue for good measure.
The next parts needed were sides and a base. I already had a piece of scrap wood that was the perfect size for a base. I used an old floppy and CDROM to size the width which just happens to be the width of the mobo minus the wood thickness of the sides.
I sawed this board down –
– to make two identical sides, like this:
The bottom was secured with four drywall screws.
And the top was secured with six drywall screws, as well.
Kind of a “rough” look but it’s fine by my tastes. I’m not that into system looks.
I mounted my good NF7-S 2.0 mobo on this carefully with two stacked standoffs –
– to get an air gap under the board:
All of the components I was going to keep from my old system fit in fine. I decided to stop using my SCSI card and DAT 3 tape drive to simplify things.
I left the drives and floppy in a drive cage, and attached it to my wooden “stand” –
– with these case cover screws:
I picked up this clear, rounded cable combo pack for $10 US at Fry’s while on vacation. Yes, I actually go shopping at computer stores while I’m on vacation. You see, there are no Fry’s on the east coast, so while I was visiting family on the west coast I couldn’t resist. ( hey, I could claim that I went to “great lengths” to write this article! 🙂
I wired up these to my floppy, CDROM and backup disk drive. My primary drive is a WD Raptor 10,000 RPM serial-ata drive that was much easier to wire up. Here’s a back shot showing the cabling:
The “rat’s nest” of power cables left over:
The power supply now sits behind the stand on its side and because it is a two fan model it actually draws some air past the disk drives with it’s “top” fan and then blows it out the fan on the end seen here.
Here is a close up showing the power supply’s two fans:
A frontal shot. Hey look I finally got ‘front mounted” fire wire and USB ports! 😉
Then next challenge of running without a case is the switches and LED’s. I started by pulling out my spare PC switch and LED “wire nest”
I made a reset switch here. Tiny wire soldering requires patience! Luckily I have it “in spades”! (that means a lot : )
I shrink wrapped the switch a bit too much, oops! I can’t see all the word “reset”.
Here is a LED for the power light:
An action shot of the power (green) and the hard drive (red) LED’s:
The whole system running with the power switch laying there too. (I cheated a little because you can see the external watercooling box to the right, but I’ll get to that next.)
The second step was to make the external water cooling box. Here’s the full tower, all steel AT case I started with skinned and gutted. Sounds kinda gross…
A good old fashioned 486 was in this case. I was donated by a friend who was cleaning out his basement. Now why anyone would want to throw good stuff like this away I don’t know. Well, maybe he isn’t as much of a pack rat as me? :
I am going to mount this new Chevy Blazer heater core. I figured new box, new pump, why not a new radiator! It just barely fits.
I had to make a 90-degree turn to get this to work. I cut a copper elbow down like so:
And reused the existing tubing to get this:
The top was next:
Well actually it’s the bottom in this picture. But you get the idea, I hope.:
After a lot of drilling out rivets and spot-welds, sheet metal snipping (did I mention it was a steel case, damn hard to snip! My arms feel stronger for the effort though :), and re-riveting, I ended up with this new ¾ size box:
Here is a shot of the rivets. I used rives because of clearance issues with screws. Basically, I had to use the same cover over so I ended up having to use the same construction methods. What I wouldn’t give for a portable spot-welder!
In hind sight, I probably could have just bought a box, but hey, I like the pride I get from a handmade product. It was also fun hammering the sheet metal into shape. (I must have been a blacksmith in a former life, but I digress.)
Measuring the case cover was easiy enough; I just sat my box in the old cover and sawed away:
I tried snips, but this case cover is even heaver gauge sheet metal than the inside! Here is one side down:
All along the way, I had been testing the components for a good fit. Here in this picture of the left side of the case – two 120mm fans, my pump, radiator and reservoir are installed.:
I used an old plastic pickle jar as a reservoir above the pump. Water cooling systems don’t have a very high volume of water, so I sized the jar such that I can have an empty system and the full jar is enough to fill the system with about half the jar’s volume of water left over. I think the jar was two quarts.
The jar is above the pump to provide water when the pump starts up so the system does not have to be primed or bled of bubbles. The flow path is out of the reservoir to pump inlet, from pump outlet to the radiator, then from the radiator to the waterblock(s), and finally return into the reservoir.
Here is a pic of the right side of the case:
The gray fittings were intended for watertight electrical conduit box junctions, but they work great here:
The fittings are 5/8″ outer diameter, so I had to stretch my ½” inner diameter tubing to get it to fit. They should be large enough to be very free flowing. I also added a 90-degree elbow and a piece of tubing to the inside of the reservoir to make the discharge below the water level of the jar to keep down the bubbles.
To get a decent front cover, I took the original case cover and cut it where the six 5¼” bays ended and then flipped it over. I drilled holes in the metal and mounted it with the same screws as I used to mount the hard drive bracket, as I mentioned earlier:
The back is almost all radiator! I am hoping for good cooling and high heat rejection capacity by using such a large radiator. I used zip ties to mount it to holes I made in the case, which is my standard method.
My first attempt at exit fittings used the water tight electrical connections and some old 5/8″ OD barbed straight female fittings I had around. For clearance reasons on my desk, I later switched to using 5/8″ OD barbed 90 degree elbows with male pipe threads on the outside and the straight firings on the inside as seen here:
I wanted to get this new box to be as simple to start up as possible, so I made a 12 volt relay circuit that would power the pump when the PC started. Here the relay is mounted to its circuit board:
It is a Radio Shack model rated at 10 amps, so it should work fine for my ~65 watt pump. Here is the back of the circuit board showing the relay soldered in:
The circuit I needed looks like this:
Here I have soldered in the 12V line. Note: the one hole next to the “Normally Closed” (NC) pin has been enlarged. I’ll talk about that below.
I used an old Molex type fan connector and some spare wire I had for a 12V input. This needs to plug into a power connector on the PC power supply, so I gave myself plenty of length here to reach:
Now to get the 120V power in was more work. I clipped the end off my new pump then I routed the wire along the top of the case and measured where I wanted the relay to be mounted.
I very carefully cut through the outer power cord insulation and the pulled it back to get to the wires. I did this so I wouldn’t have to cut more than the black wire. Here I show the black wire looped around the relay:
I had to pull it through from the cut end to get the sack I needed. This is why I cut the end off first. I was able to pull through the black wire while leaving the others. I now had unequal lengths of wire on the end of the cord. The green and white were longer by the amount the black was shorter. But I was going to cut the cord shorter later anyway. I try to show this concept in the simplified picture below:
The conductor of the power cord was larger than my circuit board holes, so I had to drill them out:
I cut the Black 120V wire and soldered it next to the “120V” in and “Normally Closed” pins. I connected the two with some solder “globs”.
Because I am paranoid about short circuits, I scraped off all of the copper around the solder joints.
For safety, fit and finish, I installed the relay in a plastic enclosure:
So the wires don’t get pulled out, they have zip ties around them. And I made notches for the 120V lines…
…and the 12V lines:
I attached my new relay box to the top of the case to keep it as far as possible from any unlikely, but possible, leaks:
The next job I tackled was making a power in plug. I used an old power supply and cut out the plug and its surrounding sheet metal hole. Here the hole is being laid out between my inlet and outlet fittings:
I riveted it in place:
I cut the power cord to length and soldered it to the plug:
Then I shrink-wrapped all exposed wires and mounted it in the case. This plug pushes through from the inside.
Here it is ready for its first test – I am powering it with the old AT power supply from the case I cut down.
It worked! I was impressed! It even shutoff when the power supply went off! Note that the water level is lower:
I realized after the fact that I needed a drain plug. (Oops!) Tipping the entire thing over to drain it was not much fun, so I added this “T” and plug. I’ll probably add a valve in the future for easier use yet.
Another change was running a 12V through a hole in the back of the case:
I added a grommet to protect the wires. I left the original 12V in wires intact and just made a Molex extension cord that was half in and half out of the case. This way, I could use the 12V line from before’s connector to power my fans. Yes, an after thought like the drain plug, but I am more of an experimental builder than a paper planner.
Here are shots of the completed box:
A lot of work, but worth it for me. Now I simply un-mount a waterblock, lift it above the case and the water drains into the reservoir. I can change our waterblocks with ease and then I just re-mount the block, start the system and it primes and bleeds itself.
If I want to test for leaks, I just need to move the case to my shop and power it with an external power supply. It’s a lot lighter and easier to use than my earlier heavy full tower system. Now I can focus my efforts on making new waterblocks. Hope you enjoyed this article.
PS: After writing this, I changed out the two 120 mm high speed fans (very loud!) for six 80 mm slow fans (quiet!). It was a drop from 200+ cfm to not quite 150 cfm, but that’s OK.
Here are the fans attached to the rad. Yes, they’re on in the picture:
I attached them with zip ties spaced off the rad with rubber grommets. The silver tape is used to close the gap:
I also added this filter:
It slides into the gap between the front bezel and the case. You can see the filter here sticking up to the top where the old drive bay openings are in the case:
That should keep my system a lot cleaner. The finishing touch was to add an old bay cover to the bottom of the case to give it a cleaner look:
That’s all folks!