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Scratch Build – In Progress Behemoth, Modular Server Rack - Update Jun 15, 2014

Discussion in 'Project Logs' started by ChromAnomaly, 10 Nov 2013.

  1. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    INTRO

    This started out as an attempt to make an efficient and easily expandable watercooled rack for my growing server farm after running in to lots of practical issues with my current 3-system case. During the design process, however, I decided that it should be able to hold an EATX system. And that it should fit into a standard rack frame. The first 2 modules quickly became quite large. So this has become more of a master node, and I will go back to the drawing board for additional modules.

    In the meantime, behold, the birth of Behemoth. Now sponsored by Performance PCs.
    [​IMG]

    CONCEPT

    Concept rendering (modeled in SketchUp and Blender, rendered in LuxRender). The components aren't very pretty, but I mostly just wanted to make sure everything would fit. I settled on thinner aluminum sheet (2mm) than I originally wanted for cost reasons, so I needed to also fit in a frame. Decided to give extruded aluminum a try.

    The render shows 3 modules stacked (currently only building 2). The base module is a dedicated radiator / pump housing. Each module has a drawer that pulls out to access the components. I didn't want to design slack in to my cables and tubing, so I will use 2 quick disconnects for the plumbing mains to detach the drawer. The PSU and all internal cables will move with the drawer for each module.

    [​IMG]

    I had the basic plates cut by eMachineShop primarily because I didn't trust myself to line up the MB standoffs and backplate. Unfortunately, this limited my design flexibility a bit because complex cuts add a fair bit of cost. I'm thinking about going back and modifying these a bit if I can pick up a scroll saw somewhere.

    [​IMG]
    [​IMG]


    FRAME ASSEMBLY

    Picked up an aluminum blade for my miter saw to cut the 72 linear feet of extruded aluminum I bought from McMaster-Carr. That was a lot of extruded aluminum. Was quite nervous when I made the first cut since the teeth on this thing look way to large for metal, but the blade worked great - I highly recommend one of these things.

    [​IMG]

    Extruded aluminum isn't that expensive, but they really get you on the fasteners. 300 of those stupid custom bolts. Ah well, it does look kind of cool. Here's the first frame, including the drawer. I used standard drawer slides instead of the extrusion ones to keep costs down, which required tapping a few holes in the extrusion. This stuff eats drill bits like that's it's job though, think I burnt up 3 of them.

    [​IMG]


    PANEL ASSEMBLY

    I decided to go with a brushed texture for the exterior panels. The top panel is raw from the machine shop, while the lower is brushed. I used a pretty aggressive 200-grit sanding block to get a deep grain, and clamped everything to a 2x4 at a 45 degree angle to keep the lines straight. Really easy to do, looks much better than the raw panel, and won't show fingerprints, etc. I went over everything with a bit of metal polish by hand after brushing.

    [​IMG]
    [​IMG]

    Brushing these panels was so easy in fact, that I decided I needed to do something more difficult to them. Here is one the interior panels in an anodizing bath. That's a 20% by weight solution of NaHSO4 (aka PH Down for swimming pools, aka sulfuric acid) hooked up to a car battery charger pushing 50Amps. The cathodes are scrap pieces of aluminum, and the plate is connected to the anode and suspended in the solution for an hour or two. After that it gets dunked in 140 deg F fabric dye for 30min, and then steamed over a boiling pan of water for 30min.

    Did I mention that I'm a chemist?

    [​IMG]

    Here's a photo of the anodized interior plates and the first 2 case modules mostly assembled. I'll get a better shot of the anodized surfaces here before too long. I had to go back and add rubber grommets to each of the bolts for the plates to keep them from vibrating against the extrusion. And I think I'm going to have to figure out a way to reinforce the bottom interior panels to support the weight of the PSU, etc. The 2 modules are held together with 1/4" alignment rods that screw in to the feet of the upper module and extend down an inch or two in to the extrusion of the bottom module. They're not going anywhere :)

    [​IMG]


    COMING SOON

    Up next (with a little luck) I will be etching the exterior panels and doing a brass inlay. More info on that if it works out :)

    Things I'm still trying to figure out (feedback welcome!):
    • Adding some complexity to the side panel cutouts.
    • Adding mesh panels without having exposed cut edges of the mesh (especially in the front acrylic face).
    • Adding support brackets for fans, etc that don't look stupid.
    • A better way to finish the butt-joined corners of the exterior panels, particularly since the rubber grommets created tiny gaps there.
    • What to use for handles for the drawers. Ideally something that can screw in to a 1/4" nut.

    Stay tuned! :)
     
    Last edited: 15 Jun 2014
  2. Theophilus_Field

    Theophilus_Field If all else fails... use the surfacing tools

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    Nice!

    The start of something unusual, a good looking server rack :thumb:
     
  3. Attila

    Attila still thinking....

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    Welcome to bit. :) That last pic looks very imposing and tasty. It has all the prerequisites that I love. Big fat chunky luminum and lots of it! :hehe:
     
  4. Gnemelf

    Gnemelf Minimodder

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    sweet, love the home anodizing :)
     
  5. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Thanks for the encouragement guys!

    Home anodizing is a lot of fun, though turns out to be pretty tricky getting an even coat on these large 400mm x 400mm sheets . . . maybe I'll post an anodizing tutorial at some point if it sounds useful.
     
  6. La carotte d l'o

    La carotte d l'o What's a Dremel?

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    Name of the project pulled me here. :D

    Now i wanna see the whole project.

    That home anodizing is something what i will try later. Tutorial would really be usefull. :)
     
  7. Boorach

    Boorach Minimodder

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    Really nice idea. Love the design and the fabrication work so far is excellent. Look forward to following the build.
     
  8. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Tutorial is posted, along with a tutorial for etching (more on that below): http://forums.bit-tech.net/showthread.php?t=265204

    Side Panel Etching

    So speaking of etching, I spent the better part of the past week testing out methods, designs, chemical bath timings, etc . . . and then I put in about 17hrs free-handing a design on my aluminum side panel before dunking it in acid today.

    Here is the first coat of asphalatum on the side panel. Nasty stuff. Shouldn't matter too much that the coat is uneven, I just need it to protect most of the surface during the acid bath.
    [​IMG]

    Ok, decided the coat needed to be a little more even on such a big plate. Here is coat #3, laying flat for this last layer.
    [​IMG]

    After the asphalatum dried, I started scraping away the resist with a wooden stick. These lines are where the acid is going to bite to etch the design.
    [​IMG]

    Adding some extra thickness to the lines to make sure the acid can get in there, and putting in some extra detail.
    [​IMG]

    All finished drawing! This took an insanely long time to complete.
    [​IMG]

    Moment of truth, here is my plate in the FeCl3 etchant. I was really nervous. I made up the solution at about 50% the normal concentration to get a nice slow etch, but then I ended up leaving the plate in for about 2 hours. At which point I realized that I had forgotten to bake on the resist to harden it :wallbash: Luckily it had taken me 3-4 days to scratch my design in to the plate, during which time the asphalatum had hardened enough that it didn't break. Came very close to ruining all that work though.
    [​IMG]

    You can tell in this closeup that the bite is a little grungy along the edges thanks to me not baking the asphalatum on. And it's not quite as deep of an etch as I was hoping for, but I couldn't leave it in any longer or the resist would have started to come apart.
    [​IMG]

    After an hour of scrubbing all that black tar off (using up about half a bottle of mineral spirits), this didn't come out half bad.
    [​IMG]

    Ok, that's one sidepanel down . . .
    [​IMG]

    Up Next . . .

    I'm taking my time with this build, as I have a lot of new stuff I want to experiment with along the way. So apologies for taking so long in between updates. Don't worry, I'm just busy trying stuff out :) I started this build well before I actually need a new computer so I can take my time with it.

    Speaking of updates, can someone tell me how to change the "updated date" in the title of this thread?? Feeling a little dumb here.

    As for experiments, here's a concept render for another part I'm about to start building.
    [​IMG]
     
  9. Boorach

    Boorach Minimodder

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    You need to edit the original post as the thread title is taken from there.
     
  10. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    :duh: thanks. I had tried that, but hadn't clicked the "advanced" button.

    And thanks for reading, wasn't sure if anyone would find that question buried in my update!
     
  11. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Watercooling Parts Arrived!

    Ok, this update is far later than I had intended. In the meantime I've purchased some land to build a house, spent a couple weeks in Germany on a business trip, had 2 computers go belly up, caught a nasty cold, and had a merry Christmas. And probably some other stuff that I don't remember. But no worries, I've taken the next week off work to make some progress on this project.

    And I have exciting news! I just ordered a boatload of watercooling parts, and in the process managed to pick up my first ever sponsor :D Performance PCs has excellent customer service, a huge selection, and the best prices I've ever found. I would have recommended them to anyone even prior to them sponsoring this project. I only wish they were local so I could stop by whenever I need a part.
    [​IMG]

    Ok, that's all. Now on to the updates.

    First a shipment from McMaster-Carr. Ah, McMaster-Carr. You are anything but subtle. My wife always knows when I get a package from you, and I think she hates you. But seriously, check out this 4 foot piece of cast acrylic. Soon this will be my reservoir. Or maybe a couple. And yes, the cardboard box is the rest of the shipment . . .
    [​IMG]

    And next the cooling parts from Performance PCs. Starting with a whole lot of fittings. So many in fact that they didn't have enough purple ones in stock. I think blue will work for this build though.
    [​IMG]
    [​IMG]

    A pair of 4 by 120mm square rads by Phobya. I sort of designed the pump box around these rads. Server racks are more or less square, and these are the only square rads I've ever seen. The photo doesn't really show the size of these things, but trust me. They are large.
    [​IMG]

    It's going to take a significant pump to get water through these rads, up 4 or 5 feet in the air, and through however many CPU blocks I eventually cram in to this thing. So I went with an Iwaki RD-20. Again, the photo doesn't exactly capture the size, but this is about the size (and weight) of a brick. I think it will do. I've got a power supply for it on order from Mouser (requires 24V instead of 12V). And it has 5/8" ID fittings, so I ended up with these ugly reducing fittings unfortunately. Going to have to hide these somehow.
    [​IMG]

    Next Steps

    • Mounting the rads and fans
    • Installing air filter screens
    • Building the pump housing and mounting the pump
    • Fabricating the reservoir(s)
     
  12. craig - toyoracer

    craig - toyoracer Minimodder

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    Nice build so far using the extruded rails. :thumb:

    Love the etched panel and great knowledge shared. :clap:
     
  13. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Thanks Craig :) I'm afraid I don't have near your fabrication skills sadly, but I do know how to play with chemicals!
     
  14. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Could have sworn I posted this update in the wee hours of this morning when I finished up for the night . . . but apparently I just dreamt that.

    Odds and Ends

    Some more parts arrived yesterday in time to kick off my week of modding. I think that's everything I need, other than the requisite unexpected trips to the hardware store. These are the power supplies that will go in the pump module. A 24V supply for the pump, and a 12V/5V supply for everything else. Sadly I couldn't find a single supply with all 3 voltages. Here's hoping I can get everything wired up correctly, not quite as easy as running everything off a standard computer PSU :worried:

    Still debating about removing these covers and replacing them with something that matches a little better.

    [​IMG]

    Also picked up some wet sandpaper. My first time wet sanding. Halfway through my first sheet of 1000 grit I'm thinking this stuff seems pretty interesting.

    [​IMG]

    And now up to 2500 grit. Kind of a neat effect. This is a photo from that perfect angle where the light catches the sand marks. Looking dead on it still has a pretty matte finish with no texture (not a mirror polish for sure), and when viewed from a steep angle it looks like it has a thick layer of varnish or something on it. I'm not sure how I feel about the swirl pattern yet, but I think I will keep it for now.

    [​IMG]

    Later in the day I was working from a rough file to 60 grit dry sandpaper all the way up through the 2500 grit wet sandpaper . . . and I decided that actually I still hate sanding. Here is my collection, and still lots more sanding to do.

    [​IMG]

    Sadly, I have to admit that all this sanding work is worth it in the end. Here is a bracket I was working on, top bracket is unsanded, bottom one is after an hour of elbow grease.

    [​IMG]

    Ok, and now that I've spent most of the day sanding, I decided to break out the worksite lamps to light up my front room. Mostly so my photos will look better to be honest. This isn't weird, is it?

    [​IMG]


    Radiator Mounts

    Speaking of brackets, here they are (unfinished obviously). Going to use these to mount the radiators to the extrusion framing. I need to mount them to the framing instead of the side panel so they will slide out when the drawer is opened. Hoping this makes repairs easy.

    [​IMG]

    First radiator mounted. Apparently I am terrible at hand drilling holes where they are supposed to be though, as this thing is crazy crooked. Really wish I had a drill press. Luckily my little sis bought me a set of needle files for Christmas, so I broke those out and went to work adjusting the mounting holes. Add a few washers to cover up the wonky holes, and this should look much better.

    [​IMG]

    Alright, much better now, and got the fans mounted as well. This time it's only my photo that's crooked :) Time to mount the second radiator. I would actually anodize these brackets, but unfortunately I've fouled my acid bath and apparently finding pH Down (it's sold for swimming pools) in the winter is pretty much impossible. Go figure.

    [​IMG]


    Next Steps

    • Mount second radiator and fans
    • Mount pump and build pump box to hide the ugly bits
    • Fabricate reservoir and mount
    • Mount power supplies and complete wiring

    Speaking of the reservoir, I had a design in mind, but now I'm not sure it's going to work. The Iwaki RD-20 pump claims that it needs a 30cm fluid head in the supply tank. That's a way taller res than I was planning. Anyone know if this is really necessary?
     
  15. KayinBlack

    KayinBlack Currently Rebuilding

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    Go to Auto Zone and get a container of battery acid. If you were close by I'd give you my containers, but you know how shipping that would go...
     
  16. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Does AutoZone still carry battery acid? Last I heard it was pretty tough to come by. pH Down is easy because no one looks at you strange when you buy it :) And while I appreciate the offer of your battery acid, I'm pretty sure that trying to ship that stuff would land us both on a government watch list :eeek:

    I'll give the battery acid a shot though. Will have to re-work my solutions since battery acid is 50% H2SO4, and I've been working from solid NaHSO4. Oh well, will make for a nice update to my anodizing guide.
     
  17. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Radiators Complete

    Finished up attaching both radiators and all the fans. Next it's on to the pump assembly.

    [​IMG]


    Pump Assembly

    Here's a basic layout of where the components will go. Looks like everything will fit at least. Though the 4 foot tall reservoir might be a little excessive. :D

    [​IMG]

    Going to be doing lots of drilling, so I picked up this crazy thing. Not exactly a drill press, but it helps. Sorta.

    [​IMG]

    Unfortunately the weather has not been cooperating with my plans to build a computer case this week. 8°F (-13°C) in the garage, and I'm cutting angle iron. And that's with a space heater running. :brrr:

    [​IMG]

    Adding an extra brace below the pump and PSUs. That's 1/8" of solid aluminum mounted to 1" extrusion rails. Hopefully that's enough to get rid of any vibration.

    [​IMG]

    A brief break from working with aluminum to construct the reservoir. This is my first time working with cast acrylic, and my first ever reservoir build. I probably could have bought a res like this and saved the trouble, but the point was to see if I could do it and try something more complex next time.

    Hardest part of building the res - finding the center of these round disks. For anyone who doesn't know this trick, draw ~3 lines of equal length across the edges of the circle. Placement and angle don't matter, as long as the line ends at the edges of the circle. Mark the center point of each line. Now draw a line at a right angle to each edge line starting from the center point. The lines will intersect at the circle's center.

    [​IMG]

    Actually tapping the reservoir on the sides wasn't particularly easy either. I ended up using a 7/16" spade bit for a pilot hole (instead of the recommended 11.8mm bit, which is near impossible to find). Spade bits aren't so great for acrylic, but it seems to have worked. Far better than the step bit I originally tried. Don't do that. Unfortunately the spade bit rendered the drill press thingy pretty useless, as the bit was too long. I had to rig it up above the res on wood blocks, which made holding both the drill and the workpiece a bit tricky.

    I also tried a variety of ways to flatten the curved side of the res around the pilot hole to make good seal with the hardware I will install, but everything I tried made a mess. My plan currently is to build up a little silicone caulk around the perimeter of the hole to make the seal.

    And here's why I decided to build my res in the middle of working on the pump assembly - I couldn't resist the temptation to do some chemistry. Yay for solvent welding, this stuff is fun. I may have also glued some random bits of acrylic together in to strange shapes just because I could :)

    [​IMG]

    Here's the finished res. It still has the protective paper on one face of the end discs, that's why they look a bit yellow in the photo. I still need to add that silicone seal around the holes, but this will do for now.

    [​IMG]

    Ok, time to start making the housing for the pump assembly. This is mostly just to cover up the ugly hose clamps to step down the pump tubing from 5/8" to 1/2". Unfortunately I couldn't find any other fittings to do this in an attractive manner. But I think the housing will look pretty interesting anyway, and also cover up the unmatched finishes on the PSUs.

    [​IMG]

    There are going to be a LOT of these tiny little screws in this frame . . . Having second thoughts about my assembly technique at this point, there must be a better way to do this . . .

    [​IMG]

    But in the end I think I like the way the brass screws look on the aluminum frame. Now I just need to polish this thing up a bit, hopefully without taking the whole thing apart. Unfortunately thanks to my lack of skill with a drill, each of these connection points has a semi-unique hole pattern. So it only goes together one way, thus the individually labeled holes in the above photo. Oops.

    [​IMG]


    Next Steps

    • Cut mesh panels for pump housing
    • Install pump housing and preliminary tubing
    • Seal and install res
    • Wire up the pump module
     
  18. Knighthammer

    Knighthammer What's a Dremel?

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    I like where this is going =)
     
  19. Hukkel

    Hukkel James' minion

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    That is a very cool design. Keep up the good work!
     
  20. ChromAnomaly

    ChromAnomaly What's a Dremel?

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    Thanks guys! Hope it ends up as good as you are imagining :)
     

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