There are countless different types of screws, bolts, and other fasteners and fixings. Machine screws are one of the more widely used products among dozens of standard fastener types.
Despite their widespread use, there is no strict definition of a machine screw. The term ‘machine screws’ covers a broad range of fastener varieties.
Stainless steel machine screws
Brass machine screws
Plated machine screws
Slotted or flat-head machine screws
Phillips head machine screws
Torx head and hex head machine screws
Fillister or cheese-head machine screws
Pan head machine screws
Tamper-resistant machine screws
Machine screws can be either coarse-threaded or fine-threaded, and are usually available with a wide range of head types, as demonstrated above. So, what is a machine screw, and how can you easily define one? Moreover, how exactly are machine screws different from other types of bolts or fixings?
The simple answer is that machine screws are typically distinguished from other common fasteners like wood screws by their physical features and intended uses. Here are some of their typical characteristics:
1. Standard machine screws are usually smaller in both length and diameter compared to many other types of bolts and fasteners.
2. Machine screws are almost always blunt-ended (flat-tipped), unlike many other screw types that taper to a sharp point.
3. Although not always the case, most machine screws are fully threaded, with the threading running the full length of the shank from just below the head to the end.
4. Machine screws are generally stronger than many other screw types. They are manufactured to high standards using refined techniques, which results in better overall quality, precision, and thread uniformity.
5. Machine screws are typically designed with finer and more accurate threads than alternative fasteners. They are generally intended for use with a pre-drilled, internally threaded hole or a nut.
6. Machine screws are most often used for securely fastening metal parts together in various types of machinery, construction, vehicles, engines, tool assembly, electronic devices, and large-scale industrial equipment.
7. Machine screws are sometimes abbreviated to 'MS'. In certain specific applications, some types of machine screws might also be referred to as 'stove bolts'.
Machine screws are most commonly used for securely fastening metal parts and panels together. This is a daily necessity in various industrial, manufacturing, construction, assembly, process, and production settings.
Using machine screws is similar to using any other type of screw or bolt. Here are the steps for using machine screws:
1. You use a machine screw by drilling or tapping it into a pre-drilled hole or nut, using either a manual or powered screwdriver.
2. Power tools are often used with machine screws because they are typically required for heavy-duty or industrial-scale assembly and construction tasks.
3. In most cases, machine screws are used with a nut and driven into a pre-drilled (tapped) hole. When using a nut with a machine screw, the nut usually goes behind the rearmost component or part being fastened.
4. Machine screws are versatile and are often used to join two or more different parts or components. They are also chosen to hold down or sandwich gaskets and membranes, as well as being used on terminal strips and for making various electrical connections.
5. An alternative use for machine screws is to separate and secure parts or panels that need to be kept at a fixed distance from each other. This is done using a threaded coupling that allows two machine screws to be driven in from opposing directions. The required separation distance between parts will determine the length of the coupling inserted between the two fasteners.
Machine screw drive types (socket types) refer to the shape of screw driving tool you will need to fasten or unfasten a particular machine screw from a threaded hole or nut. Common machine screw socket types include:
Slot – a common standard featuring a single straight socket running across the head of the machine screw, for fastening with a flathead screwdriver.
Cross or Phillips – cross drive machine screws have an X-shaped socket in the head, providing slightly more potential torque than a standard slot drive.
Hex – hexagonal recessed drive sockets in the head of the machine screw usually indicate that they are to be driven with a hex driver or Allen wrench.
Hexalobular Recess – often called Torx or star drive, the socket takes the shape of a six-pointed star, and can only effectively be driven with a matching star drive or Torx tool.
