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It seems difficult to manufacture IKEA furniture according to the brand’s guidelines, and it becomes almost impossible when you don’t know what any material is. Of course, you know what a wooden dowel is, but which hexagonal hexagon bolt with elastic band? Do you need nuts? All these issues add unnecessary pressure to an already complicated situation. The chaos is now over. Roy Berendsohn, senior editor of Popular Mechanics, shared a quick lesson on fasteners. According to Roy, the following is a classification of the seven most common screws and bolts that every homeowner encounters in their lives.
Hexagon bolts or hex cap screws are large bolts with six-sided heads (hexagonal!), used to fix wood to wood, or to fix metal to wood. Roy said: “Unlike carriage bolts, they have a tendency to rotate when tightened, so you need to hold the bolt head with a wrench or socket, and use a second wrench to tighten (or loosen) the nut.” Hexagon bolts have small sizes. The threaded and smooth shank can be ordinary steel for internal projects, and stainless steel or galvanized for external use.
Wood screws have threaded shafts for fixing wood to wood. The threading time of these screws may vary. According to Roy, when fixing softwoods such as pine and spruce, it is best to use wood screws with fewer threads per inch. On the other hand, fine-thread wood screws should be used when connecting hardwoods. There are many types of wood screws, but the most common are round and flat. Roy explained: “The head of the round head wood screw is completely above the work piece. The head of the flat head wood screw is recessed into the work piece.” The wood screw can be ordinary steel, brass, stainless steel or weather resistant steel.
Sheet metal screws are used to fix two pieces of sheet metal together, or to connect sheet metal to other types of metal, such as pipes. These screws usually have round, flat, or even hexagonal heads. Roy said that with regard to sheet metal screws, the thing to remember is that they are thread cutting types. He explained: “The shape of the screw head allows the screw to be cut into the receiving metal of the drive screw,” he added, and they are often called “self-tapping” screws. For maximum weather resistance, they are almost always plain steel, plain steel with weathering coating, aluminum or stainless steel.
Machine screws are a mixture of small bolts and screws, used to fix metal to metal or to fix metal to plastic. In the home, they are used to fix electrical components, such as fixing lamps to electrical boxes. In such applications, a machine screw is screwed into a hole, and the matching thread is cut or “struck” in the hole. Roy said that if the holes are not punched, the machine screws need nuts.
Hexagon socket screw is a kind of mechanical screw whose cylindrical head can accommodate socket wrench. In most cases, these screws are used to fix metal to metal and need to be tightly installed to ensure a secure connection. They are usually used when items are likely to be disassembled and reassembled over time.
Hysteresis bolts (often called hysteresis screws) are usually large in diameter and long enough to penetrate deep into the wood to form a strong connection, with little chance of loosening after tightening. Common places where you can find this type of screw are decks, docks, and wooden retaining walls. Because the pressure-treated external wood is corrosive, the square head nails have a corrosion-resistant coating. Roy explained: “They are hot-dipped in zinc or made of stainless steel.”
Bracket bolts (think of the cousin of lag screws) are large bolts used with washers and nuts to hold planks together. Below the round head of the bolt is a cube-shaped extension that cuts into the wood and prevents the bolt from turning when the nut is tightened. This makes it easier to rotate the nut (you don’t have to hold the head of the bolt with a wrench) and prevents tampering. “The nut is almost always on the back of the component. Therefore, once tightened, the fastener cannot be easily loosened because the head of the carriage bolt is round (like an old rivet), so it is difficult to grasp with pliers Hold it or the wrench,” Roy explained.