Mounting a 12 RU Rack to a residential wall - Page 1
Forum section: electronics / general

author: Halcyon
author_rank: Unknown
timestamp: July 12, 2015, 02:00:26 am
content: I'm after a bit of advice from those who are good with their hands and know a thing or two about nuts and bolts.I have 12 RU comms rack which I plan to install in my new place. The empty rack is pretty heavy (I'm guessing 20-30KG). I've told the builder about it and he's going to block out the entire wall to add reinforcement (I presume just using a flat timber board of some kind between the beams/studs).The rack actually came with a hinged rear door but I'm not sure I'll trust the hinges to support the weight of the rack + equipment. After removing the door, the rear of the rack has 4 mounting holes in each corner about 12mm in diameter.What's the best way to wall-mount this rack to ensure it'll handle the weight? Once it's installed, it will never need to be removed.

author: David_AVD
author_rank: Super Contributor
timestamp: July 12, 2015, 02:52:38 am
content: Some racks are designed with wall mounting in mind. Sometimes they have the appropriate support in the rear or they have a wall mount tray option (as pictured below) to take the weight. You may still need to secure the top to stop is falling away from the wall.

author: Muttley Snickers
author_rank: Unknown
timestamp: July 12, 2015, 02:56:57 am
content: I'm not on the computer so I cant post links but can come back later and add them. We had a Radum wall swing rack to install and it also had a hinged rear access which we needed for a Redback PA and evacuation system, in addition to two 18 amp hour batteries in a battery box and some other gadgets.I wasn't satisfied with just relying on the cam lock to hold all of the weight and closing alignment was affected anyway so I added two more adjustable locking latches above and below the cam lock, these had an adjustable eye screw and we got them from either Whitworths or Bunnings, we have since mounted dozens of these cabinets and never had an issue with the hinges, if you have the room the ability to just unlatch and swing the entire cabinet to gain access to equipment, cables and connections is a fantastic feature.As this particular rack was mounted above head height it had to be secure, in your case I would use some long coach screws and first elevate and level the cabinet, mark out the mounting holes in line with the studs if they dont line up then drill new holes in the cabinet that will align with the centre of the studs, first drill out the holes in the studs with a smaller bit and use soap on the coach bolts when putting them in along with some good washers to spread the load.If the wall has not yet been plastered then get the builder to put in a couple of noggins on their side but he will need to know the vertical hole spacing of your cabinet, and think about it carefully as you cant go changing the layout afterwards, this will aslo give you room to fish cables down to the cabinet later on and dont forget to put some big holes in any existing noggins and the top plate with some draw wires. If you use plywood as the backing then you have more flexibility later with mounting but you may need to use butterfly or toggle bolts, screws might be ok but it depends on the thickness of the ply and how well it is fixed.Obviously my preference is to mount on the studs as this transfers the load straight to ground and minimises any chance of cracking plaster, also we need to consider not only the overall weight of the cabinet and it's contents but any additional items that a customer may place on top such as monitors and so on, not an issue with full height racks but smaller ones seem to double as shelves, so mounting height must be factored in particularly if you need to vacuum underneath or want the option to add another rack or storage system below at a later date.Hope this helps, a picture is worth a thousand kilobytes.Muttley

author: Monittosan
author_rank: Regular Contributor
timestamp: July 12, 2015, 03:27:28 am
content: Generally I tell the builder that a rack case or large switchboard will be mounted on a plaster wall. The chippies then add some pine 45x90mm along the studs and add a sheet of either mdf or what ever is on site at the time behind the plaster wall.Mark out the approximate size of the rack and cut out and pull through cables either through a brush plate or to mount GPO's or Data points Directly on the wall inside the rack cabinet for a clean look making sure these don't interfere with any of the equipment.Then just get a mate to hold up the rack while to screw it down with some large coach screws or roofing screws and level it up.

author: BurtyB
author_rank: Regular Contributor
timestamp: July 12, 2015, 01:14:41 pm
content: I'd advise finding a brick/block wall and use sleeve anchors - always worked well for me in the past.

author: Fraser
author_rank: Super Contributor
timestamp: July 12, 2015, 01:40:23 pm
content: You need to look carefully at the racks design. Some are flat pack that are then built with the intention that the internal load will transfer down through the four vertical corner to the base. Mounting on a wall and inserting a heavy load can lead to distortion of the chassis. Others are a welded aluminium chassis into which the panels fit. These are often capable of being wall mounted. The mounting to a wall should be done through the load bearing rear chassis parts but I am sure you already know that. Side struts from bottom front to top rear can be added inside the cabinet to maintain its shape under load if needed.When considering the mounting to a wall, you need to think about the load that will be exerted on the anchors and the angle of said load. With a populated cabinet you have shear and and tension loads at work. the tension element will be a significant factor as the cabinet load will be trying to pull the top anchors out of the wall and rotating about the bottom anchor point.30kg isn't that bad a load for a wall but if you intend to populate the cabinet with equipment, work out the addition weight and its distribution within the cabinet.In cases like this it is best to over engineer rather than take the risk of the whole lot coming away from the wall. It is possible to pull bricks/blocks out of a wall if you get it badly wrong.I personally would spread the load over more than 4 anchor points.Good luckAurora

author: Muttley Snickers
author_rank: Unknown
timestamp: July 12, 2015, 01:56:41 pm
content: Quote from: BurtyB on July 12, 2015, 01:14:41 pmWith the utmost respect, he is hanging a 12RU cabinet not a sherman tank, the timber frame can probably hold a ton of lateral load without any issue whatsoever, even a single toggle in the plaster board alone is rated for 5kg, I've mounted hundreds of large CRT screens and speakers over many years in pubs, clubs and venues on Pivotelli brackets and never once had one come down even with intoxicated idiots using them as monkey bars, and the load on these brackets is transferred to a single stud and not shared across a couple.Muttley

author: Halcyon
author_rank: Unknown
timestamp: July 12, 2015, 02:27:38 pm
content: Thanks all for the feedback. The rack itself is a Hallam rack made in Australia. It's not a cheap crap generic one so the walls of the rack itself are sturdy. Having not hung something this heavy and bulky on a wall before, I just want to be sure I'm doing it correctly.

author: Muttley Snickers
author_rank: Unknown
timestamp: July 12, 2015, 02:46:03 pm
content: You wont have a problem and will look back afterwards and realise that there was nothing at all to be concerned with, but as Aurora pointed out if it was a brick wall using Dynabolts, Loxins or Chemset then you do have to be very thorough in getting a good fixing into the bricks and making sure you have at least a few rows of bricks above your highest fixing point.Lets just whack a cabinet on the wall shall we........Wish you well.Muttley

author: Richard Crowley
author_rank: Super Contributor
timestamp: July 12, 2015, 03:25:00 pm
content: Your question wasn't clear whether you want to hard-mount the rack, or have it hinged so you can access the back?If I had to hard-mount it, I would take a couple of 2x4 studs maybe ~20 inches wide and lag bolt them into two adjacent wall studs. One for the top of the rack, and one for the bottom. Then you can bolt the rack to those cross-piece studs, again using lag bolts. Or even pre-drilled holes with T-nuts at the back of the studs and use regular machine bolts.If I wanted to hinge the rack, I would use a heavy-duty piano hinge (or 3~4 door hinges) and bolt them into a wall stud. Perhaps with a plywood back panel bolted into wall studs.

author: codeboy2k
author_rank: Super Contributor
timestamp: July 13, 2015, 02:20:57 pm
content: As has been said, find a stud, it will have the best holding power. If you need to use toggle bolts, forget the old standard metal wings. I use these Toggler SnapToggles now. They don't fall back behind the wall if you need to remove the thing hanging there. You'll never go back to the old metal butterfly wings again.These snap toggles are rated at about 100kg lateral load, although I would like to see a Consumer Report on that first

author: Richard Crowley
author_rank: Super Contributor
timestamp: July 13, 2015, 06:47:07 pm
content: Those toggle bolts that @codeboy2k mentioned are very nice and I will certainly look for them next time I need something like that.However, no matter how beefy the plaster-board is on the wall, I would NOT hang something that heavy without direct connection to the internal wall studs.

author: Bassman59
author_rank: Super Contributor
timestamp: July 14, 2015, 05:05:30 am
content: Quote from: Halcyon on July 12, 2015, 02:00:26 amThe rack accepts 19"-wide kit so figure it's something like 21" or so across. Perhaps the simplest way to mount it to a wall if the mounting holes don't line up with the studs is to bolt a cleat to the wall. It's a simple piece of 1x6 or a cut strip of plywood the width of the rack. The cleat attaches to the studs, and the rack bolts to the cleat. If you use plywood make it the size of the back of the rack so the rack mounts flush to it. If you use the 1x6 then you'll need a piece at the top of the rack and another at the bottom.