A pocket knife is an essential tool for any man’s toolkit. You never know when it’ll come in handy. Unfortunately, even the best quality pocket knife won’t hold its sharpness forever like any knife. The last thing you want is to find yourself in a position where a sharp knife is crucial to your very survival and find yours left blunt as can be from years of use and neglect.
Pocket knife sharpening is surprisingly easy to do, yet also surprisingly easy to neglect and even forget about. For this reason, we decided to put together a comprehensive guide on how to sharpen your pocket knife at home. Whether you’re dealing with flat-blade or serrated, whether you have all the right tools or need to go DIY, this article will give you the info you need to keep your blade sharp as – well – a well-sharpened knife’s edge.
Before we begin, we’d like to add a quick disclaimer that if you’re unsure about any of the advice presented in this article, try and acquire the assistance of a more experienced person or even a professional. If you’re not an adult, be sure to stay away from knives and not attempt any knife sharpening without the express supervision of a responsible adult. With that said, let’s get into it.
How to sharpen a pocket knife with a stone
If you don’t already have one, you’ll want to purchase a sharpening stone, as this is the best way to sharpen a pocket knife. If you can’t get your hands on a sharpening stone, other less conventional methods can get the job done, which we’ll get to later, but we would recommend a sharpening stone for the best results.
Which type of sharpening stone should I get?
There are three main types of sharpening stones on the market: whetstones, ceramic, and diamond. Which you purchase will depend on your sharpening requirements and budget.
Whetstones are the most common and most affordable type of sharpening stone you can get. They aren’t as fast or as durable as ceramic or diamond, but they get the job done and are easy to use.
Ceramic sharpening stones are slightly more durable than whetstones, faster to prepare, and can sharpen your knife much quicker. The only downside is that they’re a bit more challenging to use, so they might not be the best option if you’ve never used a sharpening stone before.
Like Ceramic Stones, Diamond Stones are a more advanced type of sharpening stone that can sharpen your knife very quickly and will generally last a very long time. Diamond Stones are the best type of sharpening stone you can get and are usually constructed from a metal plate with diamond-encrusted surfaces. However, as you might have guessed, they’re very expensive due to the diamond fixtures used.
Soak your sharpening stone
If you’re using a whetstone, you should first soak the stone in clean, cold water for at least 10 minutes. If you’re using a ceramic stone, you only need to soak it for around half that time. Diamond stones can be used wet or dry, but we’d recommend giving them a short soak too for the best results.
Lubricate your sharpening stone
Once your sharpening stone has been soaked, it’s time to lubricate it. This will saturate the pores in the stone to stop them from getting clogged up with the debris carved off the metal blade (known as ‘swarf’) and absorb a lot of the heat energy generated to stop the blade from warping during the sharpening process. We recommend using mineral oil for the best results.
Identify the bevel angle of the blade
The most important thing at this point is to check you’ve got the correct bevel angle for your blade. The bevel angle is the angle at which the blade chamfers off toward the knife edge. Different knives will have different bevel angles depending on their intended purpose, so it’s best to check the manufacturer’s website for the best results. Most pocket knives are bevelled at between 25 and 35 degrees.
Glide the knife along the stone
Once you know the correct bevel angle, position your knife at that angle against the stone. Glide the knife along the stone in a continuous motion whilst trying to maintain as steady of an angle as possible. You may want to purchase a sharpening guide to help with this stage if you have trouble maintaining the correct angle.
Once one side of the knife is acceptably sharpened, flip the knife over and do the other side to match in the same method outlined above.
If your sharpening stone is double-sided (i.e. it has a rough and a smooth side), you can then flip over to the smooth side to refine the edge and work out any rough chunks from the metal.
Test for sharpness and repeat if necessary
As you sharpen, periodically test the knife on something like a piece of paper to see if it’s sharp enough. Repeat until you’re satisfied with the sharpness of your pocket knife. A good test is usually to hold a piece of paper up and slice the knife against the paper at a 90-degree angle. If the knife cuts the paper without tearing or pulling it down, then it’s at optimal sharpness.
How to sharpen a serrated knife
Serrated knives don’t need to be sharpened as often as a flat-edge knife because their unique shape reduces the amount of overall contact time the blade has with the objects it’s cutting. However, the problem is that due to their awkward shape, knowing how to sharpen a serrated edge knife is a bit more challenging.
Sharpening a serrated knife with a sharpening rod
Serrated knives can’t be sharpened with an ordinary sharpening stone. Instead, they require a special ‘sharpening rod’ designed for this specific purpose. These tools tend to have a tapered diameter to be used on various sizes of serration.
Simply place the sharpening rod at a 90-degree angle to the blade at the appropriate bevel angle (this is usually around 15 degrees but be sure to check the manufacturer’s website). Then slide the rod through until it matches the diameter of the gullet (be sure to approach from the bevelled edge as most serrated knives are only bevelled on one side of the blade). You can then move the rod back and forth through the gullet (maintaining the proper angle) to sharpen it.
Once you’ve sharpened the gullet a little (a few strokes should do), check the back of the blade for a ‘burr’ – a protruding deposit of metal shavings behind the groove. This indicates that a serrated knife has been sufficiently sharpened, and you can now move on to the next gullet. Rinse and repeat for each gullet until the whole blade is sharpened end to end. You may need to adjust the position of the sharpening rod to account for changes in the groove size.
Finally, you can use a nail file or fine-grit sandpaper to file away the burrs on the back of the blade for a smooth finish.
How to sharpen a pocket knife without a whetstone
If you can’t get your hands on a whetstone, we have a few other tips on how to sharpen a pocket knife at home. Some involve other specialist sharpening tools, but there are also ways to sharpen a knife without any specialist tools at all.
How to sharpen a pocket knife with a honing rod
One way to sharpen a knife without a sharpening stone is using a honing rod. Honing rods are technically designed for ‘honing’ rather than sharpening. This means that rather than filing away blunted metal from the blade, they run along its edge to straighten it out. Regardless, it achieves a similar effect in making your blade sharper and more effective, just through different means.
The easiest way to use a honing rod is by holding it vertically against a table or countertop with the tip against the surface and a tight grip on the handle. Hold the blade at the appropriate bevel angle (as set out above) and begin by resting the blade’s heel against the top of the metal part of the rod with the tip of the knife angled upwards.
Next, slide the blade down the honing rod, maintaining the appropriate bevel angle until the tip of the blade touches the steel rod’s bottom. Your hand should remain in roughly the same position so that the angle of the blade rotates as it slides down the rod. Repeat this 5 to 10 times on each side of the blade to achieve a sharper edge.
How to sharpen a pocket knife without tools
Sometimes you just don’t have the tools at your disposal, so you’re probably wondering if there’s a way to sharpen a pocket knife without any tools. The answer is yes, and we’ll share our tricks for this with you below, but please take note that there is always a risk that these methods will damage your blade irreparably if done incorrectly, so proceed with caution.
Using a coffee mug
That’s right; you can get a sharp pocket knife with something every house is likely to have in the cupboard – a coffee mug! Ceramic is a very strong material, and coffee mugs have an almost perfectly-designed rough edge on their bottom rim for sharpening blades.
Simply flip over the coffee mug, so it’s upside down, then run your blade along it as you would a normal sharpening stone (see above for more details). This won’t be as effective as using an actual sharpening stone and is likely to do more damage to your knife if used as a long-term solution, but it gets the job done.
It doesn’t have to be a mug either; you can achieve the same effect with plates, bowls, or any ceramic utensil with a flat, rough, protruding base edge.
Okay, it may be something you’d usually find in a toolbox, but it’s not technically a tool, so we’re counting it. Sandpaper can be used to sharpen a pocket knife in much the same way as a sharpening stone.
You can either wrap the sandpaper around a wooden or metal block and sharpen as you would with a whetstone, or you can use the sandpaper directly on the blade to file down the steel (just be sure to take great care and always have the blade moving away from you to reduce the chance of any accidents).
Start with a coarser grit to file down the bulk of the material, then work your way down to a finer grit for a smoother, sharper finish.
Literally, use a stone (make sure it’s a smooth one)
It may sound ridiculous, but the very first sharpening stones were literally just rocks that had been found lying around. They worked pretty well for centuries, and they don’t do an awful job now either. Just be sure to use a smooth stone (like the type you would find at the beach); the finer the texture and flatter the surface, the better. It may take a long time, but it will get the job done.
Bear in mind that – as with any tool not designed for the job – you are inevitably going to do more damage to your blade over time using a non-conventional tool, so if you’re sharpening any good quality pocket knives that you’re particularly fond of, be sure to invest in a sharpening stone for a proper way to sharpen your pocket knife.