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Ask Slashdot: How Do I Make a High-Spec PC Waterproof? 202

jimwormold writes: I need to build a system for outdoor use, capable of withstanding a high pressure water jet! "Embedded PC," I hear you cry. Well, ideally yes. However, the system does a fair bit of number crunching on a GPU (GTX970) and there don't appear to be any such embedded systems available. The perfect solution will be as small as possible (ideally about 1.5x the size of a motherboard, and the height will be limited to accommodate the graphics card). I'm U.K.- based, so the ambient temperature will range from -5C to 30C, so I presume some sort of active temperature control would be useful.

I found this helpful discussion, but it's 14 years old. Thus, I thought I'd post my question here. Do any of you enlightened Slashdotters have insights to this problem, or know of any products that will help me achieve my goals?
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Ask Slashdot: How Do I Make a High-Spec PC Waterproof?

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  • by lgw ( 121541 ) on Saturday October 25, 2014 @06:14PM (#48231245) Journal

    Make it water-cooled! Duh.

    • This is currently modded "funny", but is actually a very good solution to the problem. With water-cooling, all electrical components, except the radiator fan, can be in an air-tight enclosure. Then get an IP rated fan [ebmpapst.com.au], or a larger, fanless radiator.

      • Then get an IP rated fan, or a larger, fanless radiator.

        The latter. Even if the fan can stand brief immersion, it probably isn't suitable for something that is exposed to water jets.

        So the ideal system would probably be something like this:

        [1] Water blocks on CPU and GPU, and possibly another air-water heat exchanger somewhere internally to keep the internal ambient temperature down.

        [2] At least one internal fan to circulate the air, keeping for example the memory modules (which should have large heat sinks) cool.

        [3] The coolant goes to an exchanger

  • by BoRegardless ( 721219 ) on Saturday October 25, 2014 @06:15PM (#48231247)

    Some servers have been designed to have the motherboard immersed/sealed in dielectric fluid in a sealed box to take the heat out, which would also be in a sealed structure. That stops the need for air as a heat transfer method. Would require waterproof electrical connectors.

    • Re:Server Techniques (Score:4, Informative)

      by Mashiki ( 184564 ) <mashiki&gmail,com> on Saturday October 25, 2014 @09:45PM (#48232165) Homepage

      I used to build cabinets for farm use, while I didn't go the immersion route I went with "the box" solution. Basically it meant that air intakes had double bends, sometimes triple bends with a drain hole at the bottom. Doors used a foam sealer, and exhaust was placed wall side. Farms are dirty places, if you're not dealing with feed dust, you're dealing with hay dust, or chemicals for plants, sprayers or livestock. There's always something that would ruin a machine quick.

    • by mspohr ( 589790 )

      This...
      Get a big vat with a sealed lid and immerse the whole thing in mineral oil. It conducts heat much better than air cooling. If the vat is big enough, convection will cool it properly; otherwise get a circulating pump.

      • I built an oil cooled machine a few years ago in a fish tank, it was really awesome looking....but....The oil makes all plastics parts and wires so brittle, that in just a few months they snap with any kind of movement. One of the add-on cards I had also had some rubber parts to the capacitors, and when the rubber expanded in the oil it just popped the capacitor right of the board. Also while gaming the oil would push 130F until I put an external radiator that was air cooled on it, if it is run for under
  • The right enclosure (Score:5, Informative)

    by plover ( 150551 ) on Saturday October 25, 2014 @06:16PM (#48231255) Homepage Journal

    NEMA rates enclosures for their ability to withstand harsh environments. Search for NEMA enclosures and pick the one that fits your machine.

    • by speederaser ( 473477 ) on Saturday October 25, 2014 @06:29PM (#48231349)

      Search for NEMA enclosures and pick the one that fits your machine.

      Here's one you might like [l-com.com] but it's not cheap at $325 each.

      • by pelgv ( 714539 )
        But that is an IP24 so it will not work for his application. So he needs IPX6 or greater (usually you will get IP66). Depending on what he means with "High pressure jet" it will be IP66 or IP65. Something like this: http://www.tteglobal.com.au/tt... [tteglobal.com.au] And then he could use a fan inside with a heater exchanger, water to the outside and another heater exchanger with a fan outside. All sealed.
      • That enclosure does not appear to be sealed, this is good from a cooling point of view but may be problematic if the environment is too wet.

    • Theres more to it than that.

      The problem is if you put something that makes lots of heat in a sealed box not much large than the item and don't make any provision to get the heat out of the box it's just going to overheat. So in addition to the sealed box you are going to have to find/build a cooling system that can collect the heat from the components on the inside and radiate it to the outside without compromising the seal on the box and without being compromised itself by the conditions outside. I would e

    • by AmiMoJo ( 196126 ) *

      In Europe it's more common to use IP ratings. IIRC the OP will need something rated at least IP68 for this application.

      As well as a sealed enclosure I'd recommend including some desiccant to absorb any moisture that does get in.

    • by flyneye ( 84093 )

      Scotch-Guard every bit of the machine that you can. It will REPEL water. It may not be a perfect solution, but, if you keep incidental water OFF the machine, it isn't as likely to wind up IN the machine.
      Unrelated, but handy, use Scotch-Guard on ANY speakers you have. Both sides. This keeps humidity (and water, beer, piss) from expanding the speaker fibers randomly to allow the balance of pull on the frame to become unequal and start scraping your speaker coils on the cylinder walls or magnet, causing heat a

  • whatchadoin? (Score:5, Interesting)

    by jjeffries ( 17675 ) on Saturday October 25, 2014 @06:17PM (#48231257)

    Can you give us curious folk a hint as to what you're doing?

  • Start here... (Score:4, Informative)

    by Anonymous Coward on Saturday October 25, 2014 @06:19PM (#48231279)

    http://www.skbspecialtycases.com/

    I deal with this kind of thing once in a while when deploying hardware in freezing conditions (down to about -60F), and the truth is there aren't many options that are as small as you want.

  • http://www.liquipel.com/ [liquipel.com]

    They coat the chips in some sort of coating that insulates them.

    Another idea which I like even better is to immerse the whole machine in mineral oil.

    It is non-conductive. Somethings might need to be insulated against the oil like harddrives but everything else can just sit in it. From what I've gathered the entire tank of mineral oil acts like a giant heat sink to such an extent that a system like that can passively cool itself WITH overclocking.

    I keep meaning to build a mineral oil

    • Comment removed (Score:5, Informative)

      by account_deleted ( 4530225 ) on Saturday October 25, 2014 @06:50PM (#48231433)
      Comment removed based on user account deletion
      • Hmmm... do you have a better solution?

        I know that Cray has some sort of chemical they use for their machines... they've been immersing machines in fluid for years. I assume something more like what they're using would be ideal. Though whatever it is has to be accessible to plebs like you and me.

    • by dgatwood ( 11270 )

      http://www.liquipel.com/

      They coat the chips in some sort of coating that insulates them.

      My first inclination would be to get the biggest heat sink I could find, fasten it to the motherboard, and build a 12V to 5V and 3.3V DC-DC converter (and 1.8V, if needed). By not starting from 110VAC, you can cut the PSU heat to a level that might be manageable without fans. Then get extension cables for any connectors that you want to keep usable, along with a couple of heavy gauge wires for your 12V leads, stick th

  • Headless? (Score:5, Interesting)

    by StevenMaurer ( 115071 ) on Saturday October 25, 2014 @06:23PM (#48231309) Homepage

    This is the big question. Because, to riff off the 14 years old discussion, wireless has progressed leaps and bounds since then. So simply putting the PC inside a waterproof chest and using a combination of WiFi, Bluetooth, and a few wireless display technologies. This is what is presently on Intel's product roadmap [pcworld.com] anyway.

    Your biggest problem is likely to be the monitor. Every means we have to produce significant amount of light (especially required for outdoor viewing), requires dissipation of heat. That means venting. Which means air holes. Which can get spray in it.

    So really the question can't be answered unless you explain the purpose of the PC. Is it there to do things like take measurements? Can it be controlled from a mobile phone? (they're much easier to seal) This is what is needed to know how to give further advice.

  • by confused one ( 671304 ) on Saturday October 25, 2014 @06:27PM (#48231337)

    You're going to have a hard time finding a high spec computer that meets your needs, because of the cooling requirement. If I were you, I'd look to industrial enclosures designed for water proof operation. (there are industrial computer enclosures) Make the system water cooled so that you can run cooling lines outside the enclosure and use an external pump and radiator; this will allow you to minimize the size of the enclosure containing the computer. You'll have to accommodate the VRMs and Southbridge, which are typically passively air cooled (but do require cooling). You might try taping off connectors and spraying the PCB with conformal coating, to reduce the damage should water get into the enclosure. Connectors can be filled with dielectric grease on the pin entry side and epoxy on the wire side to prevent water access there.

    I have never tried to do this with a computer; although, the techniques above have been used by me in other applications.

    • I would say use a high end server to do the processing and send the output to a lower end more robust system.

  • The Toughbook might be an option.
  • by Anonymous Coward

    Why don't people provide more details when asking questions? Really, you'd think a bunch of IT related people would be sick of getting questions with vague details and thus be better at making their own questions.

    Do you actually need a PC in that environment? Can you use a rugged wireless display/embedded system within reach of the jet, but connected wirelessly to the computer with the GPU that's in a safe location? This is probably the easiest and cheapest setup.

    • by u38cg ( 607297 )
      Equally, you could take it as read that he has considered obvious things like "don't put it there". It's hardly that difficult a solution to come up with. I understand your thirst for knowledge but sometimes an answer to the question is all that's required.
  • If the water jet is always present and not too warm, it could be used for cooling. Just put the computer in a waterproof aluminum box (maybe with fins?) and attach the hot parts of the computer to the box with heat pipes.
  • Encase the PC in a fireproof rubber balloon like the ones used in Formula One and fill it with perfluorocarbon (PFC), then encase that in a rust-proof metal box.
  • I need to build a system for outdoor use, capable of withstanding a high pressure water jet! "Embedded PC," I hear you cry.

    No, I cry - well, no, just say, really - "why?"

  • by localroger ( 258128 ) on Saturday October 25, 2014 @06:54PM (#48231453) Homepage
    Double enclosed is best, but you probably don't have room for that. I've been putting stuff in food processing plants for 20+ years though where the conditions (especially during cleanup) are comparable. Find the smallest Pelican case (there are generic knockoffs, if you go with one check it thoroughly before trusting it) and equip it with a thermostatic heater to keep the temperature above 70F or so all the time to limit condensation. Pack in a big bag of dessicant because without double enclosure that still won't be perfect.
    • This is the correct answer. Another company is Otter Box. Build the whole thing, pop it in the case.

      Another correct answer, do whatever heavy processing you're doing remotely and have this device just do IO and control. Stick a microcontroller in the box, so it generates less heat.

  • I have old Linksys wireless routers with DDWrt loaded out in the backyard. It's Oregon. It rains here... I used tupperware containers(or whatever fits from Home Depot), and a little hole for the power cord and some silicone calk in the hole. You can double enclose, and it'll run you maybe $10. :D
    • by SeaFox ( 739806 )

      How does it get any ventilation?

  • by Anonymous Coward on Saturday October 25, 2014 @07:05PM (#48231509)

    I'm used to IP67-IP68+(IE. IP69K) for my work in designing autonomous subs(although I have other experience from GPU mining bitcoins), but NEMA 4X is specifically designed for the high pressure water jet conditions you're describing.

    Although I'm curious WTF you're doing in a mobile/stationary weatherized application that requires a GTX970(A Jetson TK1 is easier to cool and good enough for most computer vision problems)? I'll answer your question directly instead of asking you how I can back out of your difficult design requirements:

    First off: Lets assume IP55 is good enough:
    http://cosmotec.stulz.com/en/products/ventilation/kryos-filter-fans/
    These are the most cost effective IP55 ventilation fans I've been able to find.

    If that's good enough for you: get on McMaster and order a NEMA 4X enclosure and consider yourself lucky that was all you needed. You have an industrial cooling problem, they have industrial cooling solutions. If you want some a little closer to your side of the pond: request a catalog from Rittal or get on their website and see if they have anything that meets your needs.

    If IP55 is not good enough, and nothing as generic as a cosmotec fan or a cooled Rittal enclosure can get the job done: you can start by reading all the other responses and see if anyone has a better suggestion I'm unfamiliar with. If not, your job is either impossible, no one here knows what the solution is(or isn't saying if they do), or you have to go custom. That means in house or out of house design.

    First off lets make something clear: you have a thermal management problem, not a water ingress problem. It becomes a water ingress problem when you are unable to adequately manage your thermal output without circulating air from the outside of the enclosure.

    Shedding the heat of a 500-1000W PC using nothing but convection cooling with the enclosure skin/fins is difficult in the size you've described so the easiest thing to do would be to cheat and exceed your volume constraints via an external radiator in a location where your volume constraints are less of a problem. Supposing that is not possible: in a stationary application the ground becomes a pretty good heat sink if you dig down far enough. An alluminum water block burried beneath your computer circulating water through a NEMA 4X enclosure on the surface with the CPU and GPU pimped out with watercooling blocks. Excluding that as a possibility(mobile application?): pumping the heat in to a thermally conductive chunk of material large enough to dissipate it is still your preferred solution.

    If there is no way around self-contained: you're either going to have to spend a lot of time and energy maximizing the thermally conductive surface area(doing analysis to determine it is adequate to meet your use case a high enough percentage of the time to matter), make the system fail gracefully under the conditions where it exceeds it's thermal management capabilities, optimize system thermal efficiency to the greatest extent possible by doing things like underclocking the CPU and using more CUDA/OpenCL for your code, redesigning your system(using a wireless modem to offload the processing requirements to a datacenter like Amazon AWS or even a closet at a nearby facility), or some crazy combination of all of the above in appropriate proportions to maximize the value to the customer(whoever that is) on the time frame/capital investment scale they are willing to pay for, and/or manage their expectations appropriately to where you can redefine your requirements, and/or claim it's impossible and hope a smarter/more ambitious engineer doesn't prove you wrong.

    The correct answer is so situation specific it is difficult to tell you what to do without more information. These are some of the questions I would ask. Good luck with your bizarre requirements definition. I'm sure you've been painted in to a corner for good reasons and not because of an unwillingness to compromise on the "I want everything" mentality that makes programs like the F35 and F22 so fucking expensive.

    • by Teun ( 17872 )
      I can add that with high pressure jets you cannot rely on rubber or thermo-plastic seals, the gaskets have to be metal to metal.

      For heat dissipation the whole construction should be in metal and you will have to maximise the outside surface area like with ribs.

      The first thing that comes to mind is a cilinder with a screw cap on one end and fins on the outside.

    • Thanks for the very informative answer and suggestions. In response to one of your questions about why I think I need such a high end graphics card, I need to do "real time" (ideally at 30fps) processing of 3D data. My current prototype (which isn't ingress protected in any way) runs at around 10-15fps, and with the GTX970, performance bottlenecks are no longer on the image processing side of things (uploading the images to the GPU now takes more time than the calculations), which they were using an older G

      • by Kijori ( 897770 )

        Where are these water jets coming from and why is it not possible to move the data elsewhere for processing?

        It doesn't have to be far - just far enough to get out of the water jets.

        As the GP pointed out, with the constraints that you have set out the task may be impossible. The best thing you could do would be to explain what you're trying to achieve, since it's going to save you enormous effort if the constraints can be avoided.

        • What do we have:
          Very waterproof. 3D visual processing. Can't apparently separate the back-end processing from the front-end data gathering.

          Conclusion:
          He's a member of Greenpeace or Sea Shepherd & he's trying to make a kind of autopilot to go on those little boats so they can dodge the firehoses from whaling ships. That or a Somali pirate.

      • by adolf ( 21054 )

        Hi. I have found the solution to your problem.

        Longer wires. Put the box where the high-pressure water jet isn't.

        You're welcome.

      • by Hognoxious ( 631665 ) on Sunday October 26, 2014 @08:12AM (#48233587) Homepage Journal

        Unfortunately, moving the data elsewhere for processing isn't an option - there is no guarantee of decent connectivity and the amount of data will be at least 25GB a day.

        How are you planning to transfer it, Morse Code?

        On gigabit ethernet that'd take a few minutes.

  • * A rugged box shouldn't be hard to find - look at weatherized enclosures for radio equipment or, failing that, an AC mains box made for outdoors.

    * A modern CPU and a high end GPU in an airtight box won't be easy to cool. Since your only means of heat dissipation is the surface of said enclosure, it'd better be all-metal.

    * Your next challenge is to convey heat from the CPU + GPU to the box - sounds like a job for watercooling, with regular blocks for the CPU and GPU and a third, possibly custom block attach

  • The answer of course is to update to IOS 7. [imgur.com]

  • Epoxy (Score:2, Interesting)

    by Anonymous Coward

    Many years ago, friend of mine was in army. He was in secret devision and one day they give to him a order: "Change the HDD of this PC" and they give to him new HDD, hammer and chisel.
    He has surprised, because when open PC cover see massive block of epoxy. People before just fill the PC box with epoxy and made it fully water, shock and dust proof. Simple and reliable !
    You must keep in mind that may be will have a problem with cooling of some staff like video card. You can do it with water block, if is not p

    • by tippe ( 1136385 )

      Yeah, I don't buy it. There are so many things wrong with this story that make it implausible, the least of which is that epoxy-filled devices are not intended to ever be serviced, as it is nearly impossible to do so without damaging them even more.

      Assuming that your friend was telling you the truth, I bet it's probably more a case of him falling prey to a form of "greenhorn" joke, similar to what an apprentice or new construction worker would have to endure on the job site until they proved themselves, li

  • Can you place your system somewhere safe and have remote (wireless ) sensors and peripherals?
  • This sounds like you are either too lazy or not qualified for this job. My advice is to find someone who installs this kind of thing professionally. You aren't going to impress your boss or anyone else when this fucks up due to you half-assing it based off what someone from /. told you to do.
  • Non conductive oils that completely fill the case can keep water out. Make sure the case has fins for cooling on the outside. Divers watches have used this method to assure their electronics don't drown.
  • Immersion PC. You'll already be working with a sealed case.

  • With a ~150watt GPU, plus the rest of the system, you are going to have quite a time with heat dissipation in any case that is sufficiently waterproof. Even fairly impressive looking passive heatsinks are surprisingly feeble compared to the usual 'few heatpipes, bunch of fins, actual airflow' designs that normal PC hardware uses. Even if you can add enough of them to your computer's case, you still need an excellent thermal path from the CPU and GPU to the case(for reference, Zalman released a somewhat ridi [quietpc.com]
  • Somebody mentioned a pelican case. That (or similar eg NEMA 4 or 4x) is a good start. But if you cannot get the heat out of the case it doesn't take much power to cook a PC even at -5C exterior temperature and at 30C it takes very little added power.

    It sounds like you are talking hundreds of watts. So you need to make it entirely liquid cooled. This means everything that would normally have a fan -- processor, video card, chipset, and power supply. In addition you will likely need a fan in the enclosure to

  • Add IPX8 to the high specs.

  • Simple:

    1. Put your conventional, fan-cooled PC inside a completely sealed all-metal case. (With water-tight ports for CAT-5, USB, whatever.)

    2. Line the inside of the case with Peltier junctions wired to power, through a thermostat.

    3. On the outside of the case, aligned with each Peltier junction, you place a heat sink. Heat to be transferred through the metal case.

    4. If the thermostat detects high temp inside the case, it energizes the Peltier junctions to be cold on the inside, hot on the case side.

    5. If t

  • Others have posted most of what I'd suggest. If you want to consider running heat pipes to the case and have the case act as a giant heat sink, have a look at the 2008-2014 Mac Pro cases, which are solid aluminum. They'd probably be among the best options for a case that is also a heatsink. Finned heatsinks could be added to the outside of the case.

  • I'm not sure how you will accomplish what you are looking to accomplish in the space constraints you outlined but if you do I suspect it will be using 3M's Novec 7000. [youtu.be] It aint cheap but you can fully enclose your box and it uses convection to circulate.
  • Or a recent iPad in a waterproof case?

    They're waterproof enough for what you describe.

    What's the application, anyways?

  • here's one i found only the video processor is not defined linux/win I7 processor http://www.drs-ts.com/pdf/JV5%... [drs-ts.com]
  • Or are you just trying to be cool?

    If you can live with an HD 4400 graphics enigne, you can get a Small PC iBrick, which is an Intel Mobile Core i3 processor in a sealed, watertight box with cooling fins.

    There are industrial cases available for fast food restaurants. Those can handle routine pressure washing.

  • I suspect that the problem here is that you're asking the wrong question. You are trying to solve a very hard problem - how do I run a high performance PC in a location where it will be blasted with water jets - but that's not actually what you want to do; you want to accomplish a task. You haven't posted the actual task, so all we know is that it takes place outside and there will be water jets. Even so, that's enough to make me sure that there will be a better way to solve this.

    • - What space requirements
  • I'm curious why you can't use one computer with smaller footprint (and specs) and send everything via wireless to a bigger computer which is not co-located (and therefore doesn't need the waterproofing)?

  • As many will point out, getting rid of heat is one of your larger concerns. When you say "'-5 Centigrade", do you mean it will be sitting turned off and then activated and then enabled at that temperature? If there's a chance of getting freezing and thawing ice into exposed components, there are a _lot_ of mechanical and electronic devices that do not behave well when abused this way. Simply repackaging an untested design may fail at startling moments.

    It sounds like you should talk to your local meteorologi

  • I've got some old radio gear from the military, and when you're dealing with a 300w uhf transmitter that needs to go into an unpressurized area of an aircraft, you have to go down this same road, because it needs to be AIR-tight (to a large pressure differential), not just WATER-tight.

    One unit I have here is a tube type amp. Tubes are NOT efficient. Their solution was to make a hermetically sealed case (complete with pressure gauge and what looks like a bicycle tube valve on the outside. A part of the in

  • I put together a system a few years ago for use doing offshore surveying in the surf zone. The system is carried on the back of a jet-ski type PWC, and has to withstand constant salt water spray and splash, as well as occasional immersion. It consists of a PC, a monitor, an ultrasonic depth gauge, a GPS receiver, and a custom keyboard, all mounted on the jet-ski.

    The case is an off the shelf Pelican waterproof travel case, with all connections in and out of the box through Seacon waterproof bulkhead connecto

  • Are you trying to cheap this off or do it right?

    If you're going cheap, put it in an ammo box. Force through it with a duct fan, I'd weld flanges onto the box (since I've got my MIG up and running now) to attach the up and down pipes. This solves your air circulation problems to the point that you might not even need fans in the box. Ammunition cases have rubber seals. You may have to inspect the boxes carefully to find one with a good seal. You'll still need a drain as well, and it should have a long hose a

  • Duct Tape.

    Just remember: If the women don't find you handsome, they should at least find you handy!
  • Buy an industrial aluminum external mount box with gasket sealed top and bottom you bolt on and seal.
    It must also have sealed power and monitor data entry/exit and whatever on-off/reset switch is needed.
    You need to transfer heat from the CPU to the walls. The standard CPU cooler is fine, it transfers the heat to the inside air - but you also need to couple the internal air heat to the wall. So you mount a few aluminum fanned heat sinks flat to the aluminum walls by screws to the brackets that the case w

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