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How Often Should I Have My Knives Sharpened

“How often should I get my knives sharpened?”

This is easily the most asked question that I get from my customers.

My response every time is:   It depends.

  1. It depends on the quality of the knife (the steel used, the heat treat/hardness, the grind that was put on the knife)
  2. It depends on how often you use your knives
  3. It depends on how you use your knives – what you are cutting
  4. It depends on what kind of cutting board you are using
  5. It depends on how you maintain your knives
  6. It depends on how you clean your knives
  7. It depends on how you store your knives
  8. It depends on your knife technique.  For example, do you use the cutting edge to sweep food from the cutting board?
  9. And, it depends on what YOU consider sharp.
    For example, I have a low tolerance for a dull edge. All my knives need to be razor sharp at all times.

There may be other factors… but you get the picture.
I enjoy repeat business because it means my customers trust my work, but my goal is for you to enjoy using your tools.  So let’s talk about how to maximize the performance of your knives and tools.

The question is not “how often” but “how they are treated

A knife that gets hard use is going to need more maintenance.  Meanwhile, that beautiful $600 Masamoto KS in white steel that you are afraid to use is still as sharp as it ever was after 3 years of being on display in the block.  It’s not a factor of time.  It’s about how they are treated.  The answer to that question depends on the following variables.

  • The quality of the knife
    I’ve already demonstrated that I can sharpen a cheap cafeteria butter knife to the point that it will shave the hair on your arm. The difference between a good knife and a great knife is how long they stay sharp.
  • Cutting surfaces
    Only use the following as cutting board surfaces:  wood, bamboo, and HDE (high density polyethylene).  HDE is basically a soft (usually white) polymer.  Anything else will dull or damage your knives.
  • How often and how you use your knives
    If your knife edge is hitting bone with any frequency, that may be hard use and you’ll see some nicks and rolling of the edge as a result.
  • How you store your knives
    (Stored loosely in a drawer = dull knives)
    Always store knives in a way that they are separated.
    Suggestions:  Magnetic strip, a block, or a drawer divider where each knife has its own slot.
  • How you clean your knives
    (Dishwasher = Bad;  Very very bad)
    Wash by hand and dry.  Don’t leave a knife in the sink or drying try. It just keeps moisture next to the knife.

I only have 3 knives in my kitchen that I use; a chef’s knife, a utility/carving knife, and a paring knife.  And 90% of the time I am using my chef’s knife & paring knife.  We cook every single day and those knives get used all the time.  I can go 6 – 12 months without needing to sharpen because I clean & store them right, and I use a strop & honing steel to maintain the edge.

When you pick up your knives from me, I will teach you how to do the same.

How Sharp Is My Stuff ?

There are several common ways to test sharpness:

  • The fingernail test:  will the edge grip the nail or will the edge just slide on off?
  • Hair shaving:  can you shave the hair off your arm?
  • Paper cutting:  how easily will the edge slice or push through thin paper?
  • The 3-finger test:   gauging the grabbiness of edge with just the fingerprints.

But what is “sharp”?  How do you measure sharpness?  Is there a sharpness scale or standard?  Why yes… yes there is.

The Brubacher Edge Sharpness Scale (BESS) is what I use to quantify the sharpness of a cutting edge.  BESS is administered by BESS Universal (www.bessu.org) which is a not for profit organization.  To get a BESS reading on your cutting tool’s sharpness, I use the Edge On Up Professional.  It simply measures the force required to cut a BESS certified filament.  This gives us a very good idea of how sharp the tool is.

edgeonup_pt50b-z

Now, with that said, there are factors which can skew the results one way or another.

  • Example #1:  The tool is not as sharp as measured.
    I have found that toothy edges will often sever the filament with greater ease than blades with edges sharpened to a mirror polish.  It’s not a huge difference on the scale, but it is noticeable.  The issue is that this does not fully represent the real world applications.
    Different steels have different compositions.  Some steels are carbide heavy, which means that they have very hard “teeth” at a microscopic level.  These steels are often harder to sharpen and they are more rust resistant.   Others are made from purer, high-carbon, steels. Such steels are highly valued by chefs and purists for their ability to get sharper but they require far more maintenance to prevent rust and to keep sharp.   Chefs and hunters prefer the high-carbon steels because they slice meat easier and they do so in a way that causes less cellular damage.  Yeah, I know that sounds crazy, but it is true.  Some knives rip through the meat and others slice.  And yes, we’re talking about something that is happening at a microscopic level.  And that is why a toothier edge can often show up as sharper than a less toothy edge on the BESS scale.
  • Example #2:   The tool is sharper than measured.
    I sharpened a couple of straight razors for a client.  Both razors were ready to shave when I returned them to this gentleman.  They were able to top hairs (cut hairs midway up without).  He was really happy with the results and the shave he was getting.  But one of the straight razors got dull on him faster than he expected, despite him stropping them.  I offered to check it out.  I honed it back to razor sharp and then put it on my tester.  It took over 1000 grams (that’s approximately 2.2 lbs to us Americans) for it to sever the filament.  My razor was taking 70-75 grams.  When I inspected the customer’s damascus blade, I found that even though it could slice through hair, the edge rolled hard where it was in contact with the BESS filament.  The customer’s damascus steel straight razor was using a steel that was not sufficiently hardened.  So no matter how sharp it gets, it will not keep that edge for as long as a properly hardened steel.

So, as you can see, sharpness is affected by several factors, particularly blade geometry and the qualities of the blade steel  (hardness & carbides – amount and size).  Different blades have different purposes.  Most people don’t need an axe blade to be as sharp as a knife blade.  And some knife blades need to have different geometries (type of bevel, edge angle) for different applications.  But we still need a way to to measure whether something is sharp or not and understand what that measurement means.  And that is why we have the BESS system.

I measure the sharpness of every knife before it goes out.  It has to meet my standard before I say it’s ready.  I hunt and cook… a lot… and I shave with a straight razor.  I go camping and my camp knives need to have a balance of sharpness and edge retention.  Every application is different, but each will have to meet my standard.   I invite all of my customers to tell me what your needs are.  If you want your axe to be able to shave arm hairs, then so be it.  Just let me know.  And if you want to know the BESS rating on your tool’s edge, please feel free to request it.

Bark River – A video tour

Bark River is one of my favorite knife brands.  They produce high quality semi-custom knives that serve just about every need from the sportsman to the home chef and they are widely known for having some of the most beautiful and comfortable handles. I have several of their knives and can say that they are worth every penny. They are also as attractive as they are functional.  Here’s a video tour of their manufacturing facility from “Girl in the Woods”.

Re-handling a partial tang knife

A customer recently brought in a knife to have a new handle put on.  It was a special knife because it was his wife’s mother’s knife and it had sentimental value.  From my perspective, the knife had fantastic bones.  Though it wasn’t a full-tang knife, it was made with a good steel and was a great tool.  It simply needed a solid handle.

The challenge with a partial tang knife is making the handle secure so that downward pressures do not create a fulcrum effect within the handle.  It is also a matter of aesthetics.  Since the metal tang does not extend the full length of the handle, the metal would be visible for half the length and there would be a void for the rest. So, what I did to resolve that was to remove 2 mm from the top and bottom of the tang.  And then I used a piece of black G10 liner material with the same thickness as the metal. This liner material went between the handles behind the tang, and it also went above and below the tang where I removed the metal.  This is how the tang was secured and concealed without detracting from the appearance.

The owner selected a rather exotic wood for the scales, African Blackwood.  It is a very dense, attractive wood from which woodwind instruments such as clarinets and oboes are made.  It has a beautiful grain but it is very subtle and not overly visible.  It does offer some challenges when using for knife scales.  African Blackwood is a rather oily wood and, without proper treatment and preparation, bonding with epoxy could pose a challenge.

I am confident that this knife is stronger now than it ever was in its original handle. The customer was very pleased and I am looking forward to hearing about how his wife likes it.

Working Knives: The Camp Knife

Knives are specialized tools.  Some are meant for carving.  Some are intended for cutting fruit, chopping vegetables or slicing meat or fish. Some can endure downward forces and others (such as the yanagi-ba) cannot.  And some knives are simply ornamental.
There are all sorts of different knives with many different specialized uses.

In this video I take one of my favorite camp knives (Bark River Bravo 1 in A2 steel) and put it through some exercise that would leave many other knives severely dulled if not chipped or broken.  But this knife keeps a keen edge after all of the abuse only to be back to a hair-popping edge after some passes on the strop.  Indeed, it is more than just a camp knife.  It actually falls into the category of survival knife.  The development of the Bravo 1 was a result of input from Force Recon of the U.S. Marine Corps.

This is the type of knife that can handle hard tasks such as batoning (splitting) wood, carving and light chopping, making nice, thin, curly feather sticks, fire starting, and even using the tip to drill holes.  It’s good for hunting tasks with medium & large game.  And while it can do all that and still stay sharp enough to cut rope, it’s not the right choice for filleting fish and there are other knives which are more efficient at slicing strawberries & peeling potatoes.

I do love A2 steel.  It gets sooo sharp and stays that way.