RackStuds are a product from New Zealand where we are left wondering: why did nobody think of this sooner. As part of our Datacenter #2 build-out we have expanded our capacity to test different types of products. After adding capacity in Las Vegas, Nevada, and taking a few cage nut cuts, we were in search of a better answer. A quick Google search led us to RackStuds. This three piece system is a replacement for traditional cage nuts and bolts that really is much easier to install. We sent a note to the RackStuds folks and they put us in touch with their local distributor DataCenter Gear in Cupertino, California who quickly got us a few samples for review.
RackStuds – Red versus Blue
As someone who has used cage nuts for years, I assumed that all square posts were of a uniform size. It turns out they are not, it is just that the cage nut masks complexity of slightly different sized posts. RackStuds are significantly less loose so without that play, there are two sizes: Red and Blue. When we got to the Fremont, California datacenter, we found the Red RackStuds, which work in the lab rack, did not work at the colocation facility. We changed to Blue RackStuds and they installed easily.
Our recommendation: Get a small test batch of both to see which fits your racks.
RackStuds – Installation
Installing RackStuds is incredibly easy. There are three pieces: the stud (Blue or Red), the washer (yellow) and the cap (black). Here is what the three components look like in various stages of assembly:
The installation sequence entails:
- Insert the RackStud from the front of the post. No need to reach behind like with a cage nut.
- Add the yellow washer to the front.
- Once equipment is mounted, screw on the black cap. You can hand tighten then screw it in if necessary.
This sequence had a number of advantages. First, there was no reaching around to the rear of a post. If you are replacing a 1U server with equipment above and below, this saves the mystery drop issue where a cage nut falls into oblivion while on the other side of the post. The same thing happened when we uninstalled the units. Second, because the posts are all installed simultaneously it saves a hand when having to mount equipment or rails. Third, even with a cage nut tool, I was installing RackStuds at a rate of about one every 8 seconds which is less than half the time I install cage nuts in (including screwing equipment in.) Fourth, we did have some areas of the cabinet that were blocked by a Tripp Lite zero U PDU. The RackStuds were able to be installed in tight quarters where we would have never been able to get a traditional cage nut installed.
Fitting a screwdriver there would likely mean unplugging a few machines. With RackStuds the installation could occur without disturbing the equipment already running.
Testing the limits
RackStuds are rated for 44lbs each. The team has done a fairly good job showing tests using big Cisco routers, gym weights and even vibration testing to see the limits of the Grivory plastic/ glass RackStuds. Of course, we had to see how strong they were so we tried something a little bit different. We used a Supermicro CSE-512F-350B chassis installed with a dual Xeon motherboard with heavy copper coolers. The particular chassis has a very heavy 350w power supply and is interesting because it is a 14.5″ depth but no rackmount rails. As a result, there is a lot of weight placed on the rear of the chassis creating a strong lever on the RackStuds. The result:
These snapped during the mounting process where we let the studs hold weight prior to fully securing them. A bit of momentum was generated when the rear moved down about an inch and the RackStuds snapped. On the other hand, shorter depth devices like our HP V1910-24G switches feel incredibly solid with two RackStuds on each side (see above for a photo). Mounting a medium depth server such as a Dell PowerEdge R220 using rails and RackStuds is no issue. Likewise with our Dell PowerConnect 8132 10Gbase-T switch. The key take away is that one does have to be slightly more mindful of the lever and momentum at the end of that lever.
In terms of pricing, the RackStuds seem to retail for between $0.50 and $0.62 per stud in 100 unit quantities. For those in the US that want to try ASAP here are the Amazon links with Prime shipping:
I should note that the DataCenterGear folks were extremely nice to work with. These are about 1.5-3x the cost of cage nuts (e.g. the Tripp Lite ones we use in our Las Vegas datacenter) but you probably save a minute every four installed so there certainly is value in the system.
We installed RackStuds in April but waited until the end of May to publish this review because we wanted time to see them perform over time. After hitting the limit on an install, the fact remains, they are time and time again faster to install and remove. For active development racks like we have in the Silicon Valley, these work exceptionally well with lightweight gear. We keep a wide selection on hand and did order another set for our Mountain View, CA lab and are keeping spares in Fremont, CA. Just to give one an idea regarding how impressed we were with these, we even purchased an additional 100 Reds for our test lab.