Silent DIY rack cabinet – Introduction

Build Log:

In the fall of 2015, I tried to build a rack cabinet. Only I didn’t build a cabinet. Only a frame. And when I moved last year, I completely tore it apart rather than taking it with me. While it worked for what I intended, I just wasn’t all that pleased with it.

So time for a revisit.

As you can tell by the title, the aim here is to build a cabinet, full cabinet this time, that will absorb noise while not compromising cooling too much. Initially it’ll house my NAS (“Nasira“), built into a 22″ 3U enclosure, and the Quanta LB6M, a 1U 10GbE SFP+ switch. Later I’ll be building a second virtualization server — likely to replace my HP Z600 — in a 15″ 4U enclosure.

Like previous projects, I’m adapting from another Internet posting, just with a slightly different bill of materials. Specifically…

Forum thread: 14U IKEA closed server rack

That project used 24″ base cabinets, making a 48″ deep cabinet in all. But it was designed to blend in as a TV stand. And it used an open-air rack. Instead I’m going with 15″ wall cabinets. And I’m using separate rails instead of a pre-fab rack. And I’m not interested in the degree of fan control he provides.

IKEA’s SEKTION kitchen wall cabinets offer plenty of room for building a rack cabinet. They come only in 15″ depth, but widths from 12″ out to 36″. If you need a longer cabinet — such as for this project — you can take two cabinets and join them together at the back.

For a rack cabinet, I recommend either the 21″ or 24″ width, depending on your overall goals and what will be in the rack. The frame is made from ¾” particleboard. So a 21″ frame will have an internal width of 19.5″. Almost perfect for the rails I intend to use. Making it perfect requires ⅛” thick aluminum (or something similar) to give the proper spacing to meet EIA-310 standard. It’d also mean bolting the rails to the particleboard.

And if I wasn’t concerned about noise, and didn’t have the NAS or anything all that weight, that’d be the way to go. Buy the 21″ wide cabinet, even go with a base cabinet to get the 24″ depth, aluminum or washers for proper spacing, drill holes for mounting the rails. Instant rack cabinet for under 100 USD. But… not much room for sound damping. And strength might not be the greatest since the frames, again, are particle board.

For the 24″ wide cabinet, I would need to account for the additional 1.5″ on each side. That extra 3″ of room will allow for a lot more room for sound damping material. Exactly what I want for this project. It also requires some framing to accommodate that extra width. Which will also provide some extra strength.

Slots will be cut into the bottom of the cabinet at the front and back for 80mm fans. Or possibly have the rear fans at the top. I’ll decide that later. I settled on using the Noctua NF-R8 redux-1200 fans, which can move about 21 CFM at under 10 dB/A (again, this is in part about controlling noise). I’ll likely use 4 or 5 of them on each end of the cabinet.

The 30″ cabinet can support up to 16U internally, but I’ll be using 12U rails from Reliable Hardware Company since I already have them from a previous attempt at a smaller cabinet. That’ll leave about 7.5″ of additional room, but given I’ll have fans at the front and back, I’ll need room for fan cables and a power brick. So it should all work out in the end on that.

So after all that discussion, what am I building?

I’m going to use two of the 24″ wide, 30″ tall wall cabinets, four 12U rails (two pairs), and some kind of sound damping or absorbing material to create a quiet rack cabinet.

* * * * *

Initial bill of materials:

  • 2 of IKEA SEKTION wall cabinets, item no. 702.654.50
  • 2 of Reliable Hardware Company 12U rails (sold as pairs) – item no. RH-12-SRR-A

The cabinets are advertised at 14.75″ deep, but they’re actually 14.25″ deep. I didn’t worry about cabinet doors at the moment.

The 30″ cabinet (referenced item above) will support up to 16U, but not with much room at the top and bottom for sound damping, so 14U would be better. The 40″ cabinet can support up to 20U. The 20″ cabinet can support only 10U with about a quarter inch to spare. Item numbers and links for rail sets:

So that’ll be it for now. Next iteration should be building the cabinet, starting with the frame.