From: Roy Roberts Subject: rax Date: Mon, 30 Oct 1995 14:36:13 -0800 (PST) X-Pmflags: 34078848 For home studio guys, getting rack boxes are a real problem. They don't make any sound, yet they can set you back hundreds of dollars. If you have a few basic tools, though you can build cheap racks. Here's how: A rack is a box. Boxes are easy to build. Build a box. After messing around a bit I came up with this method for making sturdy boxes: Materials & Tools needed: 3/8" Interior Plywood (1/2 4'x8' sheet for one rack) 8' 1"x1" pine board. strips. 1" sheetrock or wood screws. EITHER: Pre-drilled rack rails & matching mounting screws. OR: standard shelving rails & 1/4" furring strips. 1/4" machine screws (with big heads). 1/4" screw tap & matching drill bits. Saw, drill, tape measure, screwdriver and/or screw bits for the drill. The first decision is how deep to make the box. You want it to be deep enough to completely contain the equipment, including cabling in back. So, measure how deep your deepest rack unit is, and add an inch or two for the front (so all the knobs and sliders are recessed) and four to five inches for the cabling in back. For width, the rack units themselves are 19 inches wide, but you want to add a 1/4" or so for some slack on the sides. If you're like me, you're not going to get it exactly right when you cut, so leave a margin of error. If you get it too narrow, nothing will fit! Height? Well, a single-up rack unit is 3 inches high. If you need more than 12 rack spaces, I'd advice building two. These are not SKB space-age plastic boxes, so if you go too high you're going to get a hernia lifting the thing. 10-12 spaces is a good theoretical maximum. So decide on height, and add a couple of inches for reasons given below. Now you have to cut some plywood. 3/8" plywood is thick enough. You can go thicker, but you're going to end up with a heavy box. The sides will be as wide as the depth you've decided on, and as high as the height you've decided on. The top and bottom will be 19 inches wide, plus twice the thickness of the plywood you're using. Measure repeatedly to get this right, and use a T-Square to draw the cut lines, or your box won't be square. To construct a stable box, use screws. Don't get screws that are too long, or screws will stick through the wood all over the place. If you're using 3/8" plywood, get screws no longer than one inch, as they just have to go through the plywood and into a 1"x1" strip. When you screw your box together, don't be afraid to use lots of screws -- they hold it together after all, and adjacent screws act as strain relief for each other. Get some 1"x1" or 1"x2" pine strips, cut them a couple of inches shorter than the depth of the box. Screw these centered into the top and bottom of each side, flush with the top (or bottom). At the front of the box, you'll want the pine strips recessed enough that the rack railing can fit in front of it. The idea here is that to get a sturdy box, you've got to have something to screw into that's sturdier than the end of plywood. Using strips inside the box gives the screws something solid to bite into. For extra sturdiness, glue the pine strips to the sides before screwing them in. Once you've got the strip on the sides of the box, you're ready to add the top and bottom of the box. Before you attach the top and bottom, get a rack module and put it between the sides. Then position the sides on the bottom of the box and adjust them so that the rack unit fits snug, but not tight, at the face. Mark where the sides hit the bottom of the box, and use the marks to guide you as you attach the sides to the bottom. To do the top, flip it over and repeat the process. Now you've got a box. The pine strips used to secure screws shouldn't prevent a rack unit from fitting into the top or the bottom of the box, since most rack units are narrower behind the ears than 19". Now you want to attach the rack rails to the sides of the front of the box. You can either buy pre-drilled rack rails from Parts Express (800) 338-0531 or do what I did -- booger up your own. To make your own rack rails, you start with those shelving rails you use to attach shelves to a wall, and 1/4" furring strips. At the front of the box, screw these to the sides of the box, with a furring strip between the shelving rails and the side. The furring strip brings the shelving rails out just enough that the rack screws will fit through the face of the rack modules. In order to attach the rack units, you need some mounting holes in the edges of the shelving rail. Here's what you do: Select a box of machine screws with large heads, but fairly thin shafts. 1/4" screws are about as big as you can sink into the 1/2" thick shelf rack. Now go to the section of your hardware emporium where the drilling gadgets are, and find a hole tap that will match the size and thread of the screw, and the drill bit the hole tap needs to drill the hole. Then it's just a matter of marking the screw holes along the shelf rack, drilling them, and using the tap to thread them. With the cost of all the wood, the screw tap & drill bit, the shelving rails, wood screws and machine screws, you should be able to build a couple of twelve-up racks for less than $50. They won't be SKB ATA approved shock mounted racks, but they won't cost $300 either. If you want to get fancier, you can do things like put detachable doors on the front and back, and casters on the bottom. If you're really ambitious, you can glue carpeting on the outside, or tolex. But don't get too fancy, or you might as well have bought a commercial rack in the first place! -- [Be Brave, Be Resourceful, but above all, Be Flexible! -- Gumby's Motto] kent.williams@cadsi.com [Kent Williams/CADSI/2651 Crosspark Rd/Coralville IA 52241/(319)626-6700] >From mrk@gvgdsd.GVG.TEK.COM Wed Aug 2 10:34:54 PDT 1995 In article <3vlelr$kdv@insosf1.netins.net> Kent Williams writes: >Height? Well, a single-up rack unit is 3 inches high. A single RU is nominally 1.75 inches. Here's the rest of the story: The dimensions of a standard two space 19" rack are: |<-------------------- 19.062 +/-0.032 -------------------->| _________________________________________________________________________ | | | | | | |<------------------ 18.312 +/-0.062 ------------------>| | | | |___________________________________________________________| | 0.312| | | | | | | | o | | o | | | | | | | | 0.625| | | | | | | | | | | | | | o | | o | | | | | | | | 0.625| | | | | | | | | | | | | | o | | o | | 0.500| | |<--------------- 17.750 +0.062, -0 --------------->| | | | | o | | o | | | | | | | | 0.625| | | | | | | | | | | | | | o | | o | | | | | | | | 0.625| | | | | | | | | | | | | | o | | o | | 0.312| | | | | | | |___|___________________________________________________|___| | | | | | | | | | |_____|___________________________________________________________|_____| 1) All dimensions in inches. 2) Extrapolate for additional height racks. 3) The holes are to be tapped for 10-32 screws or drilled to accomodate the clips that provide a "stand-alone" nut. The latter are advantageous because they allow one to simply replace the clip/nut if one strips out a hole, rather than having to replace the entire rail. 4) The holes in the middle of each space are actually optional, but should be included for "universal" mounting. Some gear, such as the Alesis 1622 mixer require them if all mounting holes are to have screws installed. 5) Panel thicknesses, and therefore the desired setback of the rails from the front of their supporting members, are quite variable, and may range from 0.125 to 0.312. -- ============================================================================ Michael Kesti | "And like, one and one don't make Grass Valley Group | two, one and one make one." mrk@gvgdsd.GVG.TEK.COM | - The Who, Bargain