The humble hand file is a such a common tool that you've probably used one at some point. But most people are using them incorrectly. A file should not be used in a "sawing" motion (pressed back-and-forth), but rather pushed forward then lifted off the work piece each time.
The cutting teeth on a file are forward-facing, which means they work only when the file is moved in that direction. Drawing a file back towards against the workpiece can bend the teeth and permanently damage the tool—and files cannot be sharpened. However, they should be cleaned regularly using a file card, which is a particular kind of wire brush.
There are other types of strokes like draw filing that push the file in a sideways motion to create finer shaving. Just remember to never pull a file back, only push it forward.
Here's a great primer on all types of files and how to use them.
Timothy is a lifelong DIY enthusiast who is fixated on smart home tech, beautiful tools, and wrenching on his FJ62 Land Cruiser. He’s the DIY editor at Popular Mechanics and also the founder of the home improvement site, Charles & Hudson, the Webby-nominated family site, Built by Kids, and Tool Crave. When not working, you’ll find him on his board or bike enjoying the LA weather with his family and friends. Follow him on Instagram and Twitter.
