Tips & Techniques » Self-Sharpening Blades | Do They Work? Do self-sharpening rotary blades actually self-sharpen? Theshort answer is, yes. Since every United Rotary Trimmer comes equipped with a self-sharpening rotary blade, it isgood practice to know how your equipment functions. Let’s take a look. Getting to Know the Rotary Trimmer To start, the rotary trimmers work because they contain a self-sharpeningrevolving blade that slides along a track making cuts in both directions. Cuttingin both directions makes cutting for a left handed person just as easy as for aright handed person. The rotary blade is mostly enclosed, with only a verysmall section exposed where the cut is made. Because of this, the chance forinjury under normal operation is eliminated, making this one of the safest and mostpopular options for a trimmer. Self-Sharpening Rotary Blade, How it Works The idea of a self-sharpening blade is to keep the blade sharpfor a crisp clean cut, every time. The trimmer accomplishes this by it’sdesign. As the blade housing unit glides along the rail, the rotary blade slidesalong the other blade, the metal edge of the base. Due to the angle at whichthe rotary blade is mounted, as it glides along the stationary metal edge, it activelysharpens and hones the cutting edge with every rotation. This action is verysimilar to sharpening a knife. Paper does not have to be present inorder for this to take place. Why it Works and the Benefits Now that you know the engineering behind the idea, let’s talk about the benefits and why it works better than a cutter without a self-sharpening feature. Blades without this function will dull over time and may develop small chips or nicks in the blade. This will have a negative effect on your edges and give you poor cuts, possibly without you noticing because of the gradual dulling that occurs over time . With self-sharpening blades, that gradual dulling does not happen, it maintains it’s like-new sharp edge through the life of the blade. Self-sharpening blades will also automatically fix any chips or nicks that may occur in the blade edge. This will give you a consistent clean cut, every time, and when working with important prints, this is a big deal. Here are some of the benefits self-sharpening rotary blades offer over non self-sharpening blades… Longer, higher quality blade life Crisper and more precise cuts More pages per cut Less cutting effort Less money spent on new blades Will I Ever Need to Buy a New Blade? This technology is always sharpening and maintaining the blade edge, but is not self-replenishing. Metal does wear down over time and will need to be replaced at some point. This will depend upon how often you use it, the type of paper being cut, the amount of paper being cut per pass, as well as many other determining factors. Once you determine that the blade needs replacing, contact us for help or replacement parts here. Find our complete line of Rotary Trimmers here. To check pricing or to purchase one of our Rotary Trimmers, you can find them here. Close up of the underside of the United rotary paper trimmer rotary blade running along the stationary blades edge. This is the whole rotary blade head unit that glides along the rail. From this view, you can easily see the small portion of the rotary blade that is exposed for cutting. This is also a good visual for realizing how the rotary blade makes cuts in both directions. Here you can see the angle of the the rotary blade running along the stationary blades edge. This angle is ideal for self-sharpening and getting the most precise cuts. Here you can see from the side where the rotary blade is positioned and how inaccessible it is, for safety purposes. The blade housing is purposefully designed to keep you safe. Full view of our United RT26 - 26" Tabletop Rotary Trimmer. We offer 18", 37", and 51" rotary trimmers as well.