When you have a job to do, knowing the right tools and supplies to use will help you complete your tasks as efficiently as possible. Even the screws you use play a crucial role in securing your build, and there are hundreds of varieties to choose from.
Nearly all types of fasteners boil down to two essential types — wood and metal screws — each with unique properties that are beneficial in certain situations. Understanding the differences between wood and metal screws will allow you to make the most of your time on the job.
Before we compare wood screws vs. metal sheet screws, it’s worth acknowledging what these two varieties have in common. Both wood and metal screws serve similar purposes — fastening objects together. They often have similar or identical metallic compositions and are available in standard lengths between 0.25 and 3 inches. Both types of screws are drivable using the same tools, like screwdrivers or power tools, and come with flat, round, oval, Phillips and other head shapes.
While they are alike in function and utility, wood and metal screws feature different properties that distinguish them for their specific roles.
Wood screws are similar to metal screws in some ways, but their differences allow them to serve a specific purpose. As the name would suggest, wood screws are best for fastening materials like plywood, lumber or other types of wood. A few key design features make wood screws ideal when working with these softer materials.
For one, wood fasteners feature coarse threading (fewer threads per inch), usually only up to an inch in length. Additionally, wood screws feature smooth shanks or threadless sections underneath the screw’s head. Wood screws’ partially threaded design allows for a strong hold, and it also stops the screw from turning when the thread runs out. A screw can split or crack wooden material if it drives too far, so partially threaded shanks protect your materials while providing a firm hold that lasts.
Metal screws differ from wood screws in their design and specific function, featuring design elements geared toward fastening metal-based materials and hard plastics.
Metal screws feature longer threads than wood screws, usually at least two inches in length. These longer threads also have a higher pitch — or threads per square inch — and they cover the entire body below the head.
Since they frequently serve to fasten materials like sheet metal, metal screws are often self-tapping. Few metal materials are pre-drilled with holes, so it’s sometimes necessary to use screws that can create their own pilot holes for maximum efficiency. Self-tapping metal fasteners can pierce thin metals with ease to cut their own threads and provide a firm hold.
A relatively new design, wood to metal screws feature wings directly above the drill bit tip of the screw with a machine screw thread of 24 threads per inch. The purpose of these wings is that they will ream out the wood, while the drill bit is drilling through, so that the wood doesn’t bind up in the threads before the drill bit starts drilling into the metal. Once the wings hit the metal, the wings will break off. The reaming process is why we call these reamers.
In summary, metal and wood screws have a lot in common regarding their size options and general function, but they feature design elements for unique situations. Wood screws have coarser threads with smooth shanks below the head, while metal screws consist of finer threads that cover the entire body. While you can use either screw for any job in a pinch, these fasteners deliver their best performance when used for their intended purposes.