Rethinking my rackmount project
 

As some of you might know i've made a few posts in the past about watercooling & rackmounting all of my pcs. I'm currently building the rackmount cases (and i'm making some progress, although exams are holding me back atm).
The original plan was one rad for the entire system (and one/two pump(s)), but seeing that small evergreen unit , i'm wondering how small a rad/waterblock(/pump) combo can be... and if i can fit it in a 2U (maybe 1U) case...

Maybe it would work without pump, maybe a micro/maxi-jet pump (or something similar sized) would work. Main problem would be the size of the rad though...

Anyone having an opinion on this? Just seemed an interesting idea...

There's another thread on this forum discussing about watercooling a rackmount PC.
If somehow you can manage to fit a BIµ, a low-profile WB and a maxijet (or other small inline pump) you've won. That would mean 2U though. The frontal area of a 1U rack is too low to fit any kind of rad.

I am far along into an identical project, though I've broken from the 19" rackmount specification. Check out the following link:

http://users.adelphia.net/~jnsholcom...erproject1.htm

It describes to a button what I'm doing in my project. It wouldn't be hard to keep it in the 19" spec, though you'd just need to use a different radiator.

You might want to consider researching the WC/FC units sometimes used in rackmount applications for MPI servers. I know they're out there, cause I modeled one for my first 6 unit MPI.

I know, read most (if not all) of them, and i started about 3 of them.

I would prefer to stay away from expensive radiators like those BIs...

airspirit: i know... i've watched your project with great interest, and it's nice to know that i'm not the only one :) Although my project is a bit more work, as i construct the cabinet and rackmount cases myself too, i eventualy plan to setup a page about that.

punish3r: i'll look into those... no idea what they are though

There are heatercores that will fit, just look them up in the DB.

If only the database would be in a useful, non-microsoft format (it isn't that well supported under freebsd/linux), and openoffice can't do a thing with the .xls files either

edit: got mdbtools working, but the dimensions table doesn't contain any info i could use (no L, W, D, In or Out data shows up)

Take a look at 2-636 (VW), 2-766 (Renault) and 2-563 (GM).

Hmm ... once I take a peek at some Linux based DB systems, I may port the thing. I just haven't had time to experiment with it. I've had ... other projects to deal with.

the GM one would be hard to fit.. the renault one is a tiny bit too large, and the VW one is too large as well :(

Oh well... guess i'll go with one big rad for the entire system...
maybe use a rad/pump/res loop to cool the water, and have each unit fetch its own water... (big shared, cooler rad, n+1 pumps), that would alow me to use smaller pumps, or maybe 1 pump... bah... can't figure it out, any advice?

and airspirit, the easiest would be to make a small database (even exporting everything to a text file would work) and writing a small cgi/php script and put it on the net :)

Hum... ok, then let's try:
2-531 (Ford). It's on the long side, but it's there!

I could probably do an imported PERL associative array structure off of a standard text file bypassing the database structure altogether ... that would be an interesting way to get it on the net so you wouldn't have to download anything ... interesting thoughts you have, young Jedi ....

*cough* young Jedi *cough*, note that i've been subscribed to this forum quite a bit longer already :D

and bigben2k, nope, sorry... that rad is too large as well, guess finding something like that would be a bit too hard then :cry:
hmm, maybe i better try to find a huge one... problem would be where to find it? (lytron on ebay? hmm... maybe a bit too uhm expensive on the shipping side)

You might be able to get JessFM to make you one, custom.

hmm nah, custom prolly means high price, and i don't want to spend too much... i also seriously doubt the cooling performance that would be possible with such a setup...
i think i'll go for 1 or 2 larger ones for the rack, still have to find suitable ones though

The young Jedi thing is along the lines of "d00d/bro/cool guy/homeboy", not having to do with age or experience at all. Sh!t, for all I know you're twice my age.

Anyway, shipping on the Lytrons isn't that bad, ranging from $12-20 depending on your location, and you can pick them up sometimes (the massive ones like mine) for anywhere from $30-$100. If you get one cheap, you can have it at your door for less than a BIX before shipping.

Just a thought.

How many computers are you putting on line, how much estimated total W load to the coolant, and how hot is the room they're in?

You know... if you could mount the heatercore flat down, and have a couple of fans blowing accross it, and exit down...

Alternatively, if you don't have the option of venting downwards, use 2-658 (3/4 in. thick) and vent front to back:

venting downward is a big no for rackmount stuff, and i doubt the efficency if mouted like that too...
i think i'll go for a big shared one, just have to find something apropriate around here...

and airspirit, i knew you ment it that way, and i also, seriously doubt that i'm twice your age unless you are 7.5-8 years old ofcource.

I'll try to mail one of the guys selling those lytrons for shipping costs to belgium, but i expect them to be pretty huge..

I plan 3 computers atm, but i'm going to add a few later on (i've built a small 15U rack), the 3 atm are a 1ghz tbird, dual p2 333 and a p2 266. That p2 266 is going to be replaced someday soon, because it eats space (2U for that little power is not worth it heh). And the room is uhm... no idea, more on the cold side i think (around 20°C? a bit less? no idea, 16-17?... and i can't find a thermometer either)

hmm bigben, that just gave me an idea for mounting one (or a few) big rad(s), i guess i could put them in 1U or 2U boxes like that last drawing and then i might be able to use those crossflow blowers to cool them... hmm

I think it would work.

There might be some airflow loss due to the change of direction, but hey, it's a small compromise to be able to fit a rad/heatercore in a 1/2U unit.

The crossflow blowers would probably work extremely well here, given their size and low noise level.

Man, I wish I had a rackmount frame!

Hmm... in a 1/2U unit, the rad wouldn't be tilted THAT much... That's my bigest concern

Yes the only problem would be finding an apropriate one. Suggestions?

Keep your eyes open for a nice journal site... :D

http://www.mpja.com/

http://www.alltronics.com

http://www.allelectronics.com

That's where I usually start...

quick search turned up nothing :(

If I were to build a watercooled rack, I'd take a full-size car rad from a smaller car, and lay it flat to form the top of the rack. Fans below it blowing up (yes, I know pushing isn't as good as pulling, but sometimes ya lose a bit of efficiency for design and stuff), and a KVM switch / network switch / etc. thats not very deep mounted at the top of the rack. The fans for the rad would be behind the switch, so effectively using up 0U of space. The racks I deal with are all 42U racks though - so we never put stuff on top of them (you can't see on top of them, we'd lose stuff up there), which is also why I'd more likely put the fans below the rad. And you can mount the rad with either both barbs at the back, or both on one side depending on whether you want to run all your "mains" level tubing (the stuff that branches to each server) down one side, or the cool on one side and the hot on the other side.

cova, i've considered doing that too... but as the rack is going to end up below my desk, it doesn't seem like a good solution to me (air path would be too restricted), nice to see people post their ideas though :)

I think i'm going with the huge rad idea... still have to figure out where to put it though, and the second problem would be the pump(s)... I have no idea how much pumpin' power i would need (i can cheap & easily get mini/maxi/micro-jets and sicce pumps). Sicce pumps look interesting, problem is that they need to be submerged (don't know if they are easy to mod to inline)

I didn't even think of that in my first post - I'm usually a supporter of inline pumps (and no rez - I think they just provide more places to leak and more liquid to leak out of them when they do) - but in the case of a modular system like this you will need a rez (every time you plug in a new computer to the system, the tubing/blocks inside that system will be filled out of the rez), and just to keep the pump quiter and locating it easier, I'd go with a submersed pump.

I'd probably run a large diameter tube down one side of the rack (like Airspirit did), and put on a reducer type thing at the bottom so that most of the pipe would be say 3" or 4", and the very bottom 6" to a foot would be wider, say 8". The thick section at the bottom would house the pump, with the pump outlet connected to a 1" tube that would come out the side of the thick part and run back up to the top with points down the side of it to connect computers to.

On the contrary, an inline unit would be easiest, and would make the most sense. You will need a decent radiator, res, and pump, but access to the pump for verification of how well it is doing is crucial for this kind of application.

Think about it. You'll have multiple computers on one loop. If your pump goes out, you are f*cked, and if you can't inspect your pump easily, you'll never know if you're about to suffer meltdown.

The res is crucially important. When filling a system, you will need plenty of fluid to act not only to help prime it (this is what I love about my Tower of Power [tm], but you probably don't want to go that route ;) ), but also to serve as a buffer in case of extreme variations in the coolant temperatures. With multiple machines on the loop, you want to be able to normalize the temperatures as much as you can before you get it to the radiator, and a reservoir is the perfect place for all of your systems to drain into, and a perfect place for your pump to prime from.

If you look at the front page of my article I pointed you to earlier, there is a diagram of a way of assembling the system using a submerged pump. It would not be difficult to build a PVC infrastructure to isolate the pump inline with the res and radiators, and with shutoff valves as well, helping isolate your system in case you needed to remove the pump for maintenance (without draining the entire thing ... though my system is easy to drain and fill, I still wish I would have done a better job of isolating the pump for maint.). I would suggest a res of approx. 6L. It would be big enough to prime a good portion of your system without taking too much U space. Just set the tank on a rack shelf. In the space below you could take 8-10U and build a wind-tunnel (the equivalent of the box I made, a completely shrouded off box, essentially, forcing all air from the fans through the radiators in order for it to escape ... works very well) to house the rad(s) and pump with the fans blowing in from the back.

All in all, you'd use about 12U, or a quarter of the typical cabinet, on your cooling components. It would still leave you 36 U for components, but everything would be assembled in a nice, easy to maintain form factor.

My $0.02

That is why i was also considering to use 2 pumps, not to increase flow rate or head, but just for reliability.

Uhm my rack is only 15U, no way i'm going to use 12U of that for cooling.

Ooh, that does make it difficult. With 15U of space, though, that is only about 27", or so, isn't it? I don't know what kind of aesthetics you're going for, but you may just want to build a "rack stand" type box that your rack sits on top of, and stick all of your WC goodies in there. It is working wonders for me (just got my second box put on a couple of days ago ... it is shweet). I have found that doing it this way makes maintanence very simple. Whenever I need access to the boxes, I can open the top case, snake the block out through the rear opening, and then just remove the computer away completely. After removing each computer one by one like that, I then have my entire WC system away from the electronics, ready to be tinkered with however I desire.

I'll have pictures of Phase 2 of my project up in the hardware section and on my project page at Adelphia soon for you to look at.

Regardless of how ghetto this started out as, it is starting to look really nice.