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Building Rackmount Cabinet for Home Use?
Timothy M. Schumann asks: "I am trying to build a small rack mount cabinet for my family to help with the clutter of our home network. I don't want to purchase a rack or cabinet pre-manufactured; I would like to build my own. However, I have been unable to find a list of physical specifications that racks and cabinets must conform to when built, so I was wondering if any Slashdot readers could help me find such information? Just for a frame of reference, I'm looking for something along the same detail level as the BTX form factor specs that can be found here. Any input on cost effective hardware choices for rack mountable UPSs, switches and/or cases is also welcome." This topic was originally discussed some two years ago, and while there was some useful information was presented, the basic question wasn't really answered. If you were going to try and build a custom rackmount enclosure for yourself (or someone else), how would you go about doing it?
Just throw all your boxes under a desk with 6 monitors on top like me.
404
That's what closets are for.
In the music industry it is done all the time- just buy the rails and bolt them to the enclosure of your choosing. It aint rocket science!
Those that suggest you "dance like no one is watching" really want to see you make a complete fool of yourself.
Just build a wooden frame. Then use #10 wood screws.
Wrap with some nice finishing wood, stain, put on varathane, and you have a nice cutom cabinet.
- - - - - - - - - - -
I am a programmer. I am paid to produce syntax not grammar. Deal with it.
I have a small area for doing a rackmount in. I do not need 60 1u boxes. Just enough room for about 5 2U (gives room for air). By having the material, it would be possible to build a small one that fits the enclosure.
I prefer the "u" in honour as it seems to be missing these days.
I would begin by measuring the equipment I intend to house. Kind of like shoes....
They are around $75 to $150 instead of cabinets which tend to be $250 - $750. As long as you have a place where you can bolt it down to the floor that's well air conditioned, you should be good to go. It's the same functionality, (holds 19" rackmount gear goodness) just not enclosed.
http://tinyurl.com/4ny52
Not why custom build a cabinet, but why, if you are _custom_ building a cabinet would you care about "physical specifications that racks and cabinets must conform to"? I find this confusing. Isn't the point just to build what you need for the equipment you have??? But I could be wrong...I have a history of missing the point of these things.
1.75 (1U) x 19.0 x 16.63/20.0
Our old office used a cupboard for rackmount hubs.
If you are not going to be taking anything out of the "cabinet" too often, you could probably get away with this, and just put 2 bits of wood 19" apart so you can screw your kit directly into these...
If you do want to take things out (as I would) it would be nice to find some metal sheets with the appropriate holes drilled - they must exist - dunno where you could buy them though...
Remember rear access (no pun) but I spend as much time behind my cabinet rewiring this and that as I do in front.
For some reason rack mount gear other than networking kit is usually about twice the price of its non rack mount equivalent - take switch boxes (KVM?) and UPS's in particular - even server rack mount kits tend to be a few hundred quid - and all you get is a few brackets and perhaps some rails...
Hence I tend to go eith shelves in my cabinets - the advantages of rack mount, but cheaper!
Some day you are going to want to move. Buy an Anvil or equivalent case on eBay with rack rails pre-installed, and wheels.
They sell the rails at various sizes, all you have to do is build the box and attach the rails. Pretty good prices too.
_ ID=17055777&St=8409&St2=66320611&St3=41899718&DS_I D=3&Product_ID=6039&DID=7
http://www.partsexpress.com/pe/showdetl.cfm?&User
If you're just looking for screw specs, this ought to do it.
More on Google
Stop-Prism.org: Opt Out of Surveillance
...specifically sound guys. They've been putting effects and amps in home-made 19' cabinets for decades. You can make it out of wood yourself. (Shielding is for wussies - the units inside are in their own enclosures)
Find good, sturdy wood 1/2 to 1 inch thick, make 4 sides of a box: top, bottom and sides. Front and back should be open. The INSIDE distance between the sides should be just a bit over 19 inch. The box should be however deep as your biggest unit (of course) plus some extra for plugs and cables.
Now comes the trick: on the inside sides put two vertical bits of wood 2 inch wide, 1/2 to 1 inch thick, flat on the sides 1 inch recessed from the front running top to bottom. This is where you'll screw in your equipment. Make sure to use nylon washers so as not to scratch your euipment.
Done.
I went to IKEA and bought a cheap-o entertainment cabinet. Nice black finish, smoke glass door on the front, and cheaper than I could have bought the parts for to build my own.
I never installed the castors, and as that puts the bottom right on the floor it easily handles the weight of my large UPS. The only problem is no rails, but I've put everything on shelves... it's only for home, after all.
If you want a 19" rack, you can buy rails and build them into your own housing. Try Middle Atlantic products from your favorite video supply retailer, such as this one (no affiliation). Buy the screws there too, to make sure you get the right size.
Try here for reasonably-priced rackmount rails. They aren't really quite proper for computers, though.
I also have a catalog from Hammond Manufacturing which sells racks piece-by-piece, including rail sets. Their catalog shows a lot of detailed schematics for their racks, as well. You can get a catalog free from their web site.
I use a couple old HP half-height racks (really using only 1 right now, 1 more sitting around). They aren't deep enough for proper cases, though, so I use shallow cases for now.
I'm planning to do the same thing as you, at some point. I've considered some $300 racks off eBay and the normal $250 shipping, but I'd rather build a nice wood-exterior cabinet that would look good in the home. Besides, I need something that is closer to 'normal' specs than the racks I have now. Rack hardware: I'd stick to eBay. Shelves, blank panels, etc. are all much cheaper that way. I also bought a rackmount APC UPS--look for one WITHOUT batteries, and shop around online for replacements. You will pay less for shipping all around, and the batteries are usually crap anyway, unless it's a trustworthy seller who says they put new batteries in it. For cable management, I prefer a simple lacer bar, unless you really have a ton of equipment. Of course, if I had money, I'd get rails and cable management arms...but I was doing good to buy the rackmount cases, as the rest was (mostly) free for me. For rackmount computer cases, I've used Case Outlet for a while. They barely speak English, but they resale decent cases at decent prices. If you are using any kind of multi-drive enclosure or removeable drive racks, be sure to gett the DEEP cases! You can also try KRI Computer for rackmount equipment. I've never bought from them before, but I've heard good things about them, and they have good prices and a good selection. Welcome to the world of Ultimate Geekdom!
How you going to handle heat and air cirulation. I see some of these answers about closets and cabinets and can just feel the heat build up. Telco racks are cheap and offer lots of air circulation. Have deep servers that need front and back mounting then use two telco racks. We mounts Suns that way all the time. If telco racks are to tall they are easy to cut down, but there are also lots of accessories for them like shelves, keyboard drawers, cable management guides, and etc. Plus easy to take apart and move it necessary.
There are a few primary concerns with building your own rackmount box.
1) Accessability - an area where many commercial rackmounts flop, let alone a home-build.
2) Temperature - when you pack 4 dual-processing Athlons into a small box, you have quite a room heater. Not only does the rackmount itself need to be ventilated, but the cooling needs of the room it's in need to be considered.
3) Appearance - is it going to sit in your living room? Or, is functionality the primary concern?
4) Power and bandwidth - How are you going to plug it all in? If appearance is an issue, what about all that ugly cat5 cabling?
5) Resources - what tools do you have? Are you like me, armed with a 1'x1'x3' toolbox filled with cheap handtools, a circular saw, and a drill, or do you have a garage full of table saws, lathes, and routers?
6) Cleanliness - I've seen a rackmounted system run 24x7 in a hosting facility for 2 years and at the end not have any noticable amount of dust. I've also seen my kids' computer downstairs accumulate over 1/2" of dust on the CPU heatsink. If the box will sit in your home, you have to account for any dust in the house. I'd recommend two boxes in your unit. A small one on the bottom, with a filter on the very bottom letting air in, and fans on the top pushing the filtered air up into the server cavity. Then, at the top of the server cavity, on the sides, have the ventilation holes that let the heated air out.
7) Dimensions - there are basically two kinds of racks. 19" used by servers, and a larger size (22'? 23'?) used for telecommunications. You can get brackets to convert the bigger to the smaller.
I assume that you have a server or two, or you wouldn't be bringing it up. Really, I wouldn't consider making my own unless I enjoyed making wooden-ish boxes or had some special need or decor to match up with. You can get a decent half-size rack on ebay for a few hundred.
-Ben
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Good article on building racks. It's musical equipment oriented, but all the same principles apply:Shavano music - constructing a rack
This space for rent.
The relevant standard he's looking for is
IEC 60297-1 Ed. 3.0, 1986. You may have to
pay a nominal fee to get it though.
When I was in university I went to the monthly surplus sales racks were available pretty often and for low prices. I could have gotten racks for as low as $10 canadian. The old DEC ones looked pretty good too. I don't see why you should have to make racks.
Gil
-- Where ever you go, don't complain, you went there!
It wasn't for computer equipment but for audio equipment. It's all standard 19" equipment though. I bought my 19" rack rails at Musician's Friend and then built a plywood box around them to house the equipment. They are quite sturdy and should perform to what you need. In our rack, we had about 100-150 pounds of equipment in our 8U rack and it holds up great! Good luck!
ikeya
---- Move SIG...For great justice!
It could be sold with the house as a built-in feature. Who knows, if you sold it to a geek it could be the closer....
From excellent karma to terible karma with a single +5 funny post...
Those relay rack are complete crap when it comes to housing anything that weighs more than a pound or two. My boss once ordered these thinking they were a great way to save money. So we have two full height relay racks housing a 2U power bar, terminal concentrator (4U), some modems (2U) and a switch (1U) while friggin' servers sit on the floor. Yeah, good move.
These things are good for telco and telco-type infrastructure. Other than that, they are garbage. Garbage!
And they use a different sized screw than everything else we have (10-32). It may be because they're Hubble, who knows.
Do daemons dream of electric sleep()?
if you build in enough room to have 2U spaces near heat-sensitive items, there are rackmount fans available that are great for getting air to the whole rack. I can't find them now, but check with a large audio vendor like Full Compass. other than the specs posted above, it doesn't seem that there is that much more to know. For computers, in the interest of further airflow support, it would be very wise to port the sides of the cabinet (assuming you are using some solid material) or even use an iron mesh instead. I think that would be reasonably attractive, surrounded by wood frame.
This doesn't work, half the time- for one thing, if the equipment is too heavy/long, you'll damage the case/rack by mounting it incorrectly(and few cases have provisions for mounting near the center of gravity).
This is especially dangerous with aluminum relay racks- you can strip the screws out just trying to get the stuff mounted; the second the guy in back lets go, the bottom screws go "BBRT!" and the bottom slams to the ground, while the tops of the rack ears are now horribly deformed.
Relay racks are only for patch panels, wire management, and SHORT depth equipment(like routers, switches, hubs).
This is a good question to ask before you buy colo space- "are my servers going to be in enclosures, or relay racks?" If they say "relay racks", run away, don't come back- clowns at work. Almost all servers need proper support- ie, front AND back mounting. Preferably with rails.
Please help metamoderate.
It's worth remembering that steel or aluminum cases lose quite a lot of heat through the walls while wooden boxes are insulators, so commercial cases are more tolerant of poor thermal design.
Panurge has posted for the last time. Thanks for the positive moderations.
Head over to http://www.hammondmfg.com/ and find a product like what you want (the rack, the case, a shelf, whatever).
Then get the diagram for it, includes all the dimensions you need. Then just build your case according to that...
Theres not enough air flow in a closet to keep your equipment cool. Enclosed racks need to have big fans to keep the air moving.
I hate those damned things, too.
/etc/default/kbd.conf or somethng like that under Solaris.
Pick up a surplus terminal server like a WTI CMS-16 or Computer PowerRack off eBay. They are almost free these days. Then configure all your equipement to use serial consoles (particularly easy if you are using Sun or DEC Alpha, equipment, not too bad for LILO-loading systems either).
Just remember to enable the alternate break sequence if you are running Sun hardware and using the Computone product (or any other concentrator which isn't "break safe"). I think it's in
Do daemons dream of electric sleep()?
I just completed my own homebrew rack, and although it wasn't exactly done cheaply I did research most of the Diy options. The most promising solution I found was using bedframe rails to rack your equipment. They're strong, cheap and readily available in custom lengths at places like Home Depot. They can be mounted to a number of framing materials. ITU standard holes are fairly easy to drill, but threading can be a problem. fortunately you can just drill oversized holes and use cheap clip-on racknuts to mount all of your equipment.
Good luck!
Put a nice quiet 100 cfm bathroom fan in the closet ceiling, exhaust any heat into your attic. For around $80.00-100.00 your heat is problem solved.
Your local telco store may help. You know, the place where they stock extra phone books, overpriced telephones, and try to sell you an overpriced cell phone plan. They sometimes have secondhand relay racks, or as I found, even full-sized server cabinets, for which they don't have a use. Ask for the person who buys commercial customer premises back office equipment.
I went to a bankruptcy auction and bought three Motorola telecomm cabinets for $1.50 (that's right, a dollar and a half). These are only about 60" high by 18" deep, so they're really just dressed up relay racks. I gave one to a client and kept the other two.
Adding rails to one of them was about $60. I ordered them through my local telephone company, because it was cheaper and better than buying angle iron, drilling holes, and threading them myself. I added wheels and some paint. My total expenditure was just over $100 per cabinet.
I also bought a used high-end server cabinet for a client from the local telco for about half the price of a new one.
Our local recycler has a division that deals with computer stuff. Anything computery they separate out and try to resell. The nice thing is, they sell it by the pound! I bought several rackmount cable management modules for about $20, less than the price of a single new one. They were just sitting in a pile on the ground. I cleaned them up, and they made a nice addition to my cheap server cabinet.
If you want to put your rack in a closet and maintain a reasonable temperature, you can buy a bathroom fan and thermostat for not much money. I think a nice quiet fan is about $75, but in a closet noise may not be an issue.
sigs, as if you care.
I went with a simple 19" post and 1x2U 5x4U chassis. Here is a page with some of the info. My Home Rack Now please be nice to my bandwidth slashdot :-(
Hello. I was lucky enough to come upon a used rack that a company was throwing away. I am now in the process of building a rackmount server. By far, the hardest part was finding a case that was inexpensive and had enough hard drive bays for my needs. After much searching, I finally found the Antec line of rackmount cases:
http://www.antec-inc.com/us/pro_rackmounts.html
I think these are fairly new, because when I first started looking, no one had stock. I got my 4U22ATX400 off of Newegg.com and I love it. It is really heavy duty and sturdy. Plus, it has drive bays up the wazzo. Finally, despite its low price ($188), it has the features of a much more expensive case.
I understand the need for a cabinet and not wanting to spend a $1,000US for something that looks nice. Buy yourself an inexpensive cabinet from Wal Mart(under $100US). Then add a few metal rails (angle iron from an old bed frame), and drill the holes to fit your need. You can buy a tap and a few screw under $10US. You can get away with a project like this for around $200 and some time. You might even be able to teach the family how to drill and tap holes too!
It's all about RTFM.
... what exactly is it that you are trying to mount. The advice in the posts so far speak about heat and power concerns as well as industry standard dimensions. Whoa! You said "home".
So let's say (old gear scenario) a hub/switch, old PC as server, cable modem, T5 cable (you said "clutter" so one assumes no wifi); typical to home needs. Negligible heat, negligible power. So what the heck do you need even a "small rack" for?
Think: a cabinet rack must necessarily have a larger footprint than the existing gear it encloses. A cabinet will have all the same wiring clutter leading in and out of it. So it's unclear what you hope to gain.
If you want to make things look nice, mount the gear out of sight (closet, furnace room (my own set up)) or stick it in a piece of furniture (as many of the posts here suggest). Total cost can be zero.
Industry went to racks primarily to make use of vertical space for the large number of units typical of an industrial set up. Clutter is addressed with trunking, bundling, and raised flooring.
"Consensus" in science is _always_ a political construct.
http://mojo.servehttp.com:8282/guides/rack_cabinet /rackmount_cabinet.asp
guide for building rack
If you're in the UK, Studiospares supply all the bits you need to bolt rack gear into your own housing, such as rack strips of various heights, nuts and bolts, and pre-made cases & flightcases by Buster Cases.
Note their directions to get the right width between the rackstrips:
Or you could go for a Designer Rack, even if just for ideas :)
I was lucky to save a server cabinet from the skip at work. At the risk of Slashdotting myself... it's here.
Co-operation beats competition
I purchased a wire shelving unit on wheels from the Container Store. I keep the rack in my closet. When I need to get to the wiring, the entire unit rolls out. Total cost was about $150 US.
Michael.
Linux : Mac
No, I'm totally serious! Get a small relay rack for cable management if you must, but chances are you don't have much/any rackmount hardware anyway, and racks are pretty expensive/unnecessary for home use. Most home-use routers and switches have screw mounts on them so you can hang them on the wall and run them with staples to wherever they have to go. If you've got your heart set on rackmount systems, buy a music rack. They're often smaller and cheaper, but they're still not "cheap." Generally, with networking stuff, if you only need one rack, you can usually do without any. The only time you NEED rackmount stuff is large installations, i.e. you'd need 50 or 100 racks.
actually, for those of us in the Northeast, it would be cool to vent it out to an ajoining room to get some of that heat.
Same thing up here in frigid Ottawa, Canada.
My servers and my main workstation are in the furnace room, adjacent to a cold air return duct on my forced-air furnace. Their heat is dragged out of the furnace room and distributed throughout the house.
I'm actually considering getting together about 30 computers to heat the house this winter. Given my furnace's estimated 70% efficiency and the cost of electricity ($0.043/kWh) and oil ($0.47/L), it's cheaper. I also calculated the heat output per unit of each fuel. I could just use baseboard heaters, but the electricity may as well do something useful (distributed clients?) on its way to becoming heat.
While my main workstation is in the furnace room, my home office is in an adjoining room. I simply put a small hole in the wall for the VGA, audio, keyboard, mouse and Palm cables. It's effectively silent in here now.
Fire and Meat. Yummy.
That's exactly what I did. I got the quietist bathroom fan I could afford, and an old electric base board thermostat. I took the thermostat and inverted the temperature element so it would come on when it got hot instead of cold. After a little fiddling with the setting I got it to come on at about 90 degrees Fahrenheit. On average the fan only runs about 10 minutes every hour, and keeps the closet temperature just fine. Total cost, about $65 US (not including the tools I already had). The only downside I can find to the set up is administrating the two servers in the closet. Most of the time I can ssh into either box, but if something goes wrong and I have to hook up a monitor it's a real pain. Other than that it's great.
In the music industry it is done all the time- just buy the rails and bolt them to the enclosure of your choosing. It aint rocket science!
That's right! Buy some rack rails. They should be available at large scrap metal yards, one can get used ones inexpensively.
Buy some tools. Absolutely required:
Measure, cut, drill. Use the mitre box and a level to make sure everything is straight, bolt the pieces together.
To make your own computer cases and rack-mount shelves, use sheet steel and/or sheet aluminum, and lots of small #6-32 machine screws and nuts to hold it all together. Buy a small sheet metal brake if you don't have one ($20-$40) so that you can make neat 90 degree bends. Pop rivets can be handy for stuff like holding the side braces onto your own shelves. I usually like to build things with machine screws and nuts. Once I've got all the sheet metal done, I either weld the seams or pop-rivet them, depending on what I need. Welds are very tough to cut, and pop-rivets have to be drilled out. Machine screws let you play with the design a little bit before making it final.
Sheet metal is dangerous to work with - it's sharp and little filings will get all over the place. A pair of good leather sheetmetal gloves will protect your hands.
Also, sheet steel comes coated with cosmolene or similar anti-corrosion coatings. You will need to wipe it off (a rag with rubbing alcohol usually works) before you spray-paint your finished cabinets. You need to paint the sheet steel (Tremclad is good for this) or else it will flash-rust in time.
If you're working with salvaged scrap steel (which I usually do), you will probably need to clean it. An angle grinder with a suitably-rated cup brush will do wonders. Remember to wear the safety glasses!
Measure twice, cut once! Take your time! This is no more difficult than carpentry.
Fire and Meat. Yummy.
I built myself a rack cabinet for my music gear about a year and a half ago. I built it out of 1/2" Medium Density Fiberboard (MDF), which is a pretty good, reasonably strong, all-purpose, cheap, and very consistent (because it's made out of sawdust glued together, basically ). My boss, who is a former contractor, uses it all the time to make shelves at work. You can get 3/4", and sometimes even 1", if you are concerned about strength.
Then all you need to build the cabinet are: a circluar saw (table mount is best if you can get to one), some wood screws, and a drill. Plus, I guess, a tape measure.
There are really only three crucial issues: securing the corners somehow so the whole cabinet doesn't wobble back and forth, making sure the screws don't crack the MDF (which can happen very easily), and making sure the two sides are as close to parallel as possible, so that your equipment will fit in correctly all the way up and down the cabinet.
I solved the first by simply screwing a big piece of scrap MDF to the back bottom half of the cabinet. There are much more elegant ways to do it, and I am sure you can figure them out.
The second simply means that you have to drill all your screw holes before you put the screws in.
The third is the most difficult; I dealt with it by using corner clamps, and got lucky. Using a square in each corner would help, or you might be able to work something out using a level, if you have one.
Rack rails are available at big music stores (Guitar Center, e.g.); small ones should be able to order them. I'm sure Fry's has them, and MicroCenter too, but I've never actually looked.
The best way (I think) to attach the rails is with carriage bolts, and I didn't find that I needed washers (since there are so many bolts all the way down the rail). Rack screws are #10-32 machine screws (at least, that's what I use), and it's best to get short brass ones -- they go in easier.
Good luck!
I bought a couple inexpensive racks like mucicians use that only had the fronts with no support for the back. These are great because I could bolt them into the concrete floor, and they're perfectly parallel, and they screws and spacing are the same as for computer gear. For my UPS, switches, and other small gear I just bolt in the front and I'm good to go. For servers with rails, I have some 2x4's at the back where I can use drywall screws to attach them. I do need to drill my own holes in the rails to make them fit, but it is cheap.
I made my office next to my storage room so the servers are in the storage room with nice heavy smoked glass doors in front of the racks. I ran mouse, keyboard, VGA Printer and a pile of cat5 cables through the wall when I built it so that I could run a KVM to control the servers from the office. Now I only have to worry about that stuff changing to USB or something before I have to run more cables. The storage room has a window in it, so when it is hot I just open the window and put a fan in the window... Cooling problem solved. I have about 8 servers, 2 switches, 2 routers, 1 large UPS and the KVM running in there with room to spare.
I built myself a rack cabinet for my music gear about a year and a half ago. I built it out of 1/2" Medium Density Fiberboard (MDF), which is a pretty good, reasonably strong, all-purpose, cheap, and very consistent (because it's made out of sawdust glued together, basically )
Oh yeah, it's a great material, except that it's flammable.
(One can, of course, make that same argument about iron and steel - ever light steel wool on fire?)
The chances of my computers catching fire are minimal, but sh*t does happen, and I kinda like having a roof over my head.
Besides, if you're going to the trouble of building the thing, you may as well do it in metal. If you've got the tools, it's really no more effort.
Fire and Meat. Yummy.
Oooh.. don't exhaust heat into the atic. That's bad. Always cut it through to the roof. That air in your closet is going to be quite warm. As we learned in science back in middle school, warm air can hold more moisture than cold air. That is to say, when the warm moist closet air cools in your atic it's going to provide you with moisture problems. This is especially true with bathroom-mounted bathroom fans (since the air is likely at 100% humidity from the shower) but I'd definately run the closet fan through the ceiling, too, just to be on the safe side.
My first encounter with rackmount was when I bought a 1950's ex-Navy radio (Hammarlund SP600JX) with an attached Collins SSB decoder. The two were nicely held together by a couple of pieces of railing.
.... all hidden by full-length curtains (I am not kidding) or solid plywood sides (no diags needed then)
I later got a super-basic rackmount that I built as follows:
- 2 x 6-foot railings, vertical, parallel
- top and bottom wooden horizontal "beams", held with wood screws, that kept the railings at the standard 19-inch distance
- two more horizontal beams, perhaps 3 feet deep, screwed on the top "across" beam through L-shaped metal strips, and to the house wall with more screws and metal strips.
- more L-strips held the railings in place with only two screws into the floor.
In practice, wall and floor made two sides of the "cabinet", all the rest was open.
I considered adding a beam in diagonal position across the top, but never did it because the structure held up alright as it was.
Warnings:
1) for this structure to hold up well, you HAVE to have a few pieces of equipment mounted at all times
2) not good for low height units, as there is NO SUPPORT OTHER THAN THE FRONT PANEL SCREWS (with my 1950's gear, this was not a problem, as it was all at least 10 inch high), and high units also help with sidewasy stability
3) I had neither kids, nor animals, nor cleaning people around the house that could get imperiled or challenge the stability of this.
Having said that, I think it's a low cost idea that could easily be improved upon, e.g with
- mounting with one wall on a side as well, i.e. using a corner of the room for 3-D stability
- diagonal braces on the sides, going from the beam-railing joint down to the wall-floor corner
-
- perhaps a solid top, with a few fans
- perhaps a number of metal sheet covers to be left in place where there's no equipment.
I think I might build one such soon, as I am prolly getting a few excellent rackmount radios (HRO, Collins...) from an elderly neighbour who abandoned his radio hobby. If I do, a future rackmount computing device will have a home ready for it too! - I hope this helps...
Dude! What the hell are you talking about? You've got to have some serious issues if you can't mount something correctly in a relay rack. Center the load, zip in four screws from the front and, sometimes, four from the back. If you've centered your load properly those bottom two screws will hold it forever, or at least until you put the top two in. If the equipment provides for rear screws you always use them as well (like power supplies).
And who the hell is this "guy in back" anyway? You make me jealous, wish I had help. I've built entire cellular telephone sites and radio repeater sites putting things in racks and rarely have help. I've even been able to mount 75 lb power supplies in relay racks by myself without damaging anything.
I know you must have been shooting for "funny" but someone modded you up as "informative" and someone is going to get the wrong idea. Relay racks will work fine for his application.
By the way, you do know that they make four point relay racks, right?
. Quit playing Monopoly with Bill. Switch to one of many non-Microsoft products today.
Keep in mind, there are two "families" of rack mounting, each with its own history and traditions.
The telco industry has been mounting equipment in "relay racks" for almost a century. You don't find many relays in them now, but back when the Western Electric Company (WECo) was making all the equipment, most of what they made were relays. Telco racks are 23 inches wide and built open, so the rack channels stand vertically and you can reach around them on all sides. They have screw holes on 1-inch centers, tapped for 12-24 screws.
Equipment mounted in "telco" racks is almost always middle-mounted. The mounting ears or flanges are located about halfway back on the chassis, meaning that the center of gravity is almost in the same plane as the rack face. This means the only force on the screws is shear load, against which they're tremendously strong. You can stand on telco gear when it's rack-mounted.
Some time after the telco industry had all this worked out, the wheel got reinvented. Deejays like to mount their mixers and effects processors in racks to manage the mess, and despite a lot of commonality between old telco gear*, they settled on racks that were 19 inches wide instead of 23. Along came the EIA to standardize this, specifying a screw thread of 10-32 and a staggered hole spacing of 1 1/4" alternating with 1/2". This gives us the "1U" size of 1 3/4". Many EIA racks don't even have threaded holes, instead they have square punchings into which you insert a "cage nut", which is easily replaced if you manage to strip the threads.
(* Many patch panels used in audio production are set up with the "longframe" or "bantam" plugs, which originated as WECo plugs on switchboards and are still used today in DS-1 patching applications.)
Mounting 19" equipment in a 23" rack would be simple enough with adapter ears. They can even compensate for the fact that most 19" equipment expects EIA hole spacing, and 23" racks invariably have WECo hole spacing. The damning difference is mid-mounting versus flush-mounting. Deejays want all their buttons and knobs to form one seamless control panel, so all their equipment has mounting ears right up at the front, with the face of the equipment. This works really well for audio gear, which is usually fairly light and doesn't stick more than a few inches behind the face of the rack.
When you try to mount a server or a UPS flush with the face of the rack, you quickly discover the mechanical limits of the screws. Because most co-lo outfits charge per vertical unit of rack space, there's a lot of pressure to make your equipment as flat as possible. This moves the center of gravity farther and farther back, while shortening the amount of rack flange over which the force will be distributed. If you get that UPS to hang there, don't even breathe on it, much less use the back edge as a stepstool while climbing into the cable tray superstructure.
When the option is available, flush-mounted equipment should always have a rear support too. This is the case with many rackmount servers, which include sliding rails for mounting. The back end of the rail must be screwed into a second rack flange, which means your cabinet needs two sets of upright channels.
For mounting deejay equipment, 19" flushmount makes sense. For mounting huge switching equipment, 23" midmount is clearly a better idea. For anything in between, it mostly depends on what options your equipment gives you. I vastly prefer mid-mounting when it's available, because it makes for a much stronger setup when all is said and done.
There are plenty of other differences between telco equipment and datacomm equipment, despite the superficial similarities. I won't get into the details of DC power, grounding, redundancy and reliability, heat dissipation, alarming, or any of the myriad "requirements" that equipment must satisfy before being located in a telco office. Suffice it to say: Datacomm equipment is happy on a desk but sometimes gets bolted into a rack. Telco equipment was designed for it.
In areas near military bases you may find a great government store called the Defense Reutilization and Marketing Office. You can bid on all kinds of used DoD stuff, including rack cabinets and hardware. I have found all-metal full-featured faraday-shielded dustproof 6' tall rack cabinets, 5' long power strips, etc. I also bought an old radar video converter just to cannibalize the 4U rackmount case. If you are with a charitable org like the Boy Scouts, you get first dibs.