Step 4- Grinding the Bevel

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With the shape and thickness of the knife steel now correctly ground, we turn our attention to grinding the actual bevel of the knife blade itself. Nothing in the knifemaking art is likely more controversial among knifemakers than the type of bevel and how one grinds it (except maybe for what steel is used)! Some makers prefer hollow grinds while others prefer flat grinds, scandi grinds…etc. While I occasionally make hollow-ground blades, I generally prefer to make flat ground blades. There really is no right or wrong answer here as both are excellent grinds, and both have their merits.

A hollow grind is simply where the sides of the knife blade are ground up against a wheel. For example, we hold the steel against the 10" wheel of our belt grinder thereby making a corresponding curvature on the blade. The blade is then drawn across the wheel while simultaneously taking the angle and front curvature of the blade into consideration. The hollow grind creates a lower cross section on the blade that is thinner for a longer period of time as it is followed toward the top of the blade in comparison to a flat grind. The benefit is greater weight reduction, and a slightly easier time sharpening the blade over the course of many years under hard usage. The downside is that the blade thickness is therefore thinner over a larger area than with a flat grind.


A flat grind is exactly as it sounds. It is a grind where rather than holding the blade against a wheel, it is instead held against a flat surface. In this case the flat platen of our grinder. Again, the blade is drawn across the belt while taking into consideration the angle of the bevel as well as the curvature of the blade. This sounds simple, but takes quite of bit of experience and practice. I can assure you that a lot of blades have gone airborne in frustration when a grind hasn't turned out as I would like. I have had an instance where a simple sneeze turned what was almost a great blade into a piece of scrap! But grinding in this manner by hand becomes more natural and almost second nature with lots of experience. 

Anyway, the flat grind creates a consistent angle across the side of the blade. Therefore the average cross section of the blade is greater than that of the hollow grind – making for a slightly stronger blade. On the negative side, it makes the blade heavier (if you consider that a negative), and also makes sharpening it over many years a more difficult task as the steels gets wider faster as you go up the blade. To overcome this later issue, we often back-bevel our blades when sharpening them. More on this later, but with this method, the average end user has a much easier time keeping the blade re-sharpened for a very long time. Furthermore, I can provide advice on how to keep the blade back-beveled and sharpened in a manner that anyone can do it with little effort. (For those who don't like to sharpen their own blade, I can do this for you at a nominal fee whenever required.)


A few years back I was hunting with a German hunter. He killed a nice buck and was testing out one of my knives, admiring the 3/16" CPM S30V steel on an initial Bushbuck prototype. This appealed to him as he said he kept breaking some knives. Upon hearing the brands (which were German with an excellent reputation), I was a bit puzzled. As he field dressed the deer he asked if I usually break open the pelvis. I usually do not, unless quartering the animal for a pack-out is required. He did, and proceeded to yank the blade toward him through the pelvis bone with his tremendous 6'5" frame. Ok, a bit rough, but good knives should be okay there. Then the blade got stuck, essentially wedged into place. He nonchalantly stood up, held a hind leg of the deer and then with his foot on the side of the knife like a car brake, placed brute force on the side of the handle to crack the pelvis open. I cringed at the gross neglect and abuse the knife was taking. Once the job was done he looked at the knife, smiled, and raved about how much he liked it. I was still in disbelief at how a nice custom knife was completely abused. Certainly the great steel, and thickness of it were brawny enough to take the abuse. However, by all accounts, the very tip should have chipped. This would have been understandable. Even though we build a stout blade, the tip of any blade is its smallest, thinnest and therefore most vulnerable part. Had the tip lodged itself in bone before receiving the type of lateral pressure he put on it, it would have broken as well. I am thinking of making blades with a 5mm thickness for that German market now. Either way, we ask that you NOT abuse ANY knife in this way! They are simply not designed to be crowbars (or screwdrivers). 

Since that time I have purposely broken many blades in testing. This usually involves a big bench vise, a pipe, and a whole lot of force. It's kind of sick to watch your knives break, but its something I do to ensure quality and give me peace of mind that I am selling a quality product. It is also through this that we found that the flat grind is slightly more durable than the hollow grind. Either will serve the user just fine – especially when used correctly and as designed.

So, before I start the actual grind, I again place layout dye on the blade steel, however, this time I do it on both sides as well as what will be the knife edge. I then run a center scribe along the edge of blade – the part that will be sharpened. Placing this center-line down the middle helps me  make sure I am grinding both sides evenly.  I also have to simultaneously pay attention to where the grind ends relative to the top and front of the blade as these must be even on both sides as well. If the angle is not the same on both sides, the blade will appear grossly geometrically disproportionate. The blue layout dye helps in the constant visual inspection of the grind lines during the process. 

I  also need to make sure the ricasso of the blade is even on both sides. The ricasso is the area where the bevel grind stops and the full thickness of the blade steel begins – usually just before the start of the handle or bolster. I mostly create straight ricassos, however, sometimes I feel a bit more artistic and blend it along a greater distance. It is really just a preference or artistic expression – there is no right or wrong. So a keen eye and good feel on the blade are important.

Again, the steel is drawn across the platen with even pressure against the abrasive belt. As with profiling, I start with an aggressive belt (ie. 36 or 50 grit) and then start to smooth out the surface with between a 180 and 300 grit belt (or an equivalent micron belt). I do not go for a perfect finish, as the blade steel still needs to be heat-treated and then finish ground. But a little extra effort here does pay off in the ease of finish grinding later. 

I also make sure to leave enough stock on the blade to both compensate for the additional grinding to take place after heat treating, as well as to help prevent any warping of the blade during the stress of the heat treatment process.

Once I am satisfied with the bevel grind, we update our checklist as always and the knife steel is ready for drilling for bolsters, handles, pommels…etc.