WARNING: Sharpening knives is inherently a dangerous activity, and extreme caution should be exercised during the sharpening process. Neither the author nor the KnifeCenter of the Internet shall be held responsible for any injuries that may occur during this process.
Most of you reading this probably know how to put a good edge on a plain blade. But what about bringing dull serrations back to life? If you are like myself - prefer a partially serrated edge (maybe a fully serrated, too!) for utility work - then knowledge of maintaining those serrations is important. Bear in mind that serrations take longer to dull than a plain edge. To best explain this, here is a quote from Spyderco's dealer catalog:
OBTAIN THE PROPER TOOLS
Second, obtain the correct sharpening tools to perform the task. Many of the sharpening kits on the market offer serration hones as options. For example, Lansky Sharpeners' LS-11 hone. The LS-11 has a "V" shaped cross section that allows it to be worked inside each tooth in a serration pattern. Spyderco's Tri-Angle Sharpmaker includes triangular shaped hones to sharpen both serrated edges as well as plain. Serration sharpeners are not limited to sharpening kits. Diamond Machining Technology (DMT®) offers their Diafold diamond serration sharpener. The Diafold has a tapered cylindrical steel rod that easily accommodates any size serration recess. When finished, the handles fold up to encase the rod so the hone can be carried safely in the pocket. Also, with the Diafold, only water is required for lubrication. Therefore, it is possible to stand at the kitchen sink while using the Diafold.
WALK THAT WALK, AND TALK THAT TALK...
Finally, having the proper tools to do the job is one thing. Another is having the proper technique to use. To sharpen the serrations on my knives, I have DMT's Diafold serration hone, in coarse grit. Therefore, the technique that I am about to describe is what I use with the Diafold. No matter which serration sharpener you purchase, please consult with the accompanying directions for the proper technique to employ. Regardless of which style kit/hone that you choose to help you in this tedious task, the same rule applies. Most factory ground serrations will have the same angle as the plain edge portion (assuming the blade is partially serrated), which means in the neighborhood of 20 to 25 degrees.
Once everything is set up, you can begin the process. Using firm pressure, work the hone in a back-and-forth motion, perpendicular to the cutting edge. Every so often, stop and feel for a raised burr on the backside of the blade. Only move on to the next tooth when you see or feel a raised burr. Once you have completed sharpening the ground side of the blade, flip the knife over. With the hone, LIGHTLY grind the burr off. The operative word here is lightly, as only the ground side of the serrations should be sharpened. After the burrs have been eliminated from the back side, what you have should be a revived serration pattern that is ready for more aggressive cutting action.
Folks, that is how sharpening serrations is done. Do not worry if you do not get the results you are hoping for the first time out, as this takes a little bit of practice. Please be careful when performing this task, as it can be dangerous (for obvious reasons) if you do not pay attention to your work. I hope the information presented in this article is of use to you in keeping your blades well honed.