Examining the Different Rackmount Screws Available
What Are Rackmount Screws?
Rackmount screws are used with racking systems, commonly to attach electronics or components to the vertical members of the system. A common example is the audio equipment used at concert venues. Servers are also often mounted on racks for organization and optimum operation.
An interesting thing about racks is that they don't have a standard thread type. It can be different depending on where you are located (often US-built racks use the imperial rack rail which requires M5 screws while in Europe you'll most often see rack strips or full hole rack rails which use M6 screws) and varies from manufacturer to manufacturer. Many rack rails on the market today actually have square tapped holes that require the use of a cage nut for mounting.
Different Rackmount Screws Available
Find the screws you're looking for here.
The original rackmount screw type has a 10-32 thread. The "10" refers to the size of screw, while the "32" designation is a count of the threads - specifically 32 threads every inch. This is still the most commonly seen rack screw on the market and is available in a few different driver styles (Torx and Phillips are common).
Becoming more popular in the industry is the 12-24 rack screw. Slightly larger (the "12" again designates a size) and with thicker, coarse threads (24 per inch as opposed to 32), the 12-24 rackmount screw is being used more and more today.
In Europe there is another type of rack rail that requires a metric rack screw. The M6 measures 6mm based on the outside diameter of the thread. Standards for the M6 screw vary, but most often an M6 x 01mm is used. Those working in the computer industry should note that HP often calls for M6 rack screws.
Unthreaded Tap Holes
You may also come across a rack that has unthreaded tap holes with a round shape. A clip nut is needed for this application and that nut needs to match the rackmount screw being used. Looking closer at the computer manufacturing industry again, you might notice that Dell has a line of rack rails specifically made with round and unthreaded holes. They are not nearly as popular as the square holes when an unthreaded rack rail is needed.
