Today I’ll be answering a reader question specifically about sharpening stainless steel knives. Let’s start by taking a look at the question I was asked first.
John’s Knife Sharpening Question
Well, I have one question. It’s a timeless one, so there must be lots of good answers.
Is there a best way to sharpen most any (non-serrated blade) stainless steel knife?
Carbon steel blades seem easy to sharpen. I once had a 440 stainless knife what would take an edge in an instant … and keep it for a while. But otherwise, for me, it’s pure guess work at whether 5, 10 or 15 minutes will produce a decent blade on any stainless knife (high dollar or cheap).
I have a nice set of 3 stones. I’ve tried various oils. The most effective technique seems to depend on pressure – LOTS OF IT! But still, after scores of years, I’m a complete novice at putting an edge on a stainless blade.
Our Response: Stainless Steel Knife Sharpening Tips
Howdy John! Excellent question. It really can be quite tricky to go from sharpening carbon steel to sharpening newer stainless steels like CPM S110V. While carbon steels are easily sharpened on Japanese waterstones or standard Arkansas stones, newer stainless steels frequently have high carbide forming allies like vanadium thrown in the mix, making them much more difficult to sharpen.
The trick is actually not in the technique you use, but rather it’s with the abrasive that’s being used to sharpen. Softer abrasives, like aluminium oxide stones, Japanese water stones, or Arkansas stones, are simply not abrasive enough to remove material and form an edge on modern stainless steels.
Ultimately, you have four options for sharpening when it comes to modern stainless steels:
Different Ways to Sharpen Stainless Steel Knives
Option #1: Sharpening Stainless Steel with Diamond Based Stones
Sticking to stones is fine so long as you go with diamond based ones like DMT. They will sharpen pretty much any steel around, as no steel is as hard as diamonds.
With diamond stones, use very light pressure, as heavy pressure will cause the diamond layer to strip away (ask me how I know!).
Diamond stones can be quite expensive, but it’s is a method that you will be very familiar with going from sharpening carbon steel to stainless steel. It takes roughly 5-10 minutes to sharpen a stainless steel blade using this method.
Option #2: Sharpening Stainless Steel with Manual Systems
Your second option is to purchase a manual system that has preset angles, and offers diamond abrasives as an option. These manual sharpening systems range from (relatively) inexpensive Spyderco Sharpmakers, to fully loaded Wicked Edge/Edge Pro systems.
The Spyderco Sharpmaker is a classic for a reason, and in my opinion, a very intuitive system.
Wicked Edge/Edge Pro style systems are much more finicky, since they have so many more adjustments and parts. Of course, Wicked Edge/Edge Pro sharpeners are frequently used by knife aficionados to put really sick mirror edges on their customs, so keep them in mind if you’re looking for something like that. The level of sharpness and how clean the edge will look won’t be rivaled by much.
That being said, the financial investment is pretty high, and it does take a while to put an edge on using those systems (about 20 minutes).
The learning curve isn’t steep, though, you can definitely manage to put on a nice edge, even without much experience, though it will take a lot more of a time investment than if you were using a Sharpmaker (which would only take about 5-10 minutes).
Option #3: Sharpening Stainless Steel with Sandpaper
The budget option. Go to your local hardware store, purchase a bunch of silicon carbide sandpaper sheets, ranging from 60 to 1200 grit, and lay them on a very flat surface, a slab of marble will do. Whilst most sandpaper is aluminium oxide based, if you go for silicon carbide, the abrasive is hard enough to grind away even the hardest stainless steel. Obviously, an extreme low grit like 60 will form an edge much quicker than the standard 220/400 grit stones. Be aware that the initial edge will be very rough, and you will have to graduate to finer grits to get an acceptable, non-toothy edge. Of course, if you like a toothy edge for cutting material like cardboard, then just take the edge up to 200 grit and leave it at that! Expect around 5-10 minutes of work using low grit.
SOG S240 NW Ranger Hunting Knife – Amazon
Option #4: Sharpening Stainless Steel with Mechanized Systems
Your last choice is to take the nuclear option and go with a mechanized system for sharpening.
Personally, I use a full sized belt grinder, running 3M trizact belts, which will put an edge on Wolverine’s claws in 20 seconds flat.
The speed at which you can sharpen a knife will really astound you, and if you’re interested, you may also be able to make your money back on the grinder by sharpening knives professionally on the side.
If you have any more questions, let me know in the comments and I’ll clear things up further!
If you have a survival, preparedness, or gear related question you’d like us to answer, don’t hesitate to let us know! Find out how to reach us via the contact page. Although we don’t publish every question we’re asked on the blog, we try our best to respond to each and every one we receive.
In case you’re interested, you can also view our past responses to reader questions here.