Finding the Sweet Spot - Positioning Your Knife from Front to Back
The easiest way to find the 'sweet spot' for a given knife is to mount the knife with the blade approximately centered in the clamp and then color in the entire bevel with a Sharpie marker. After setting the angle, lightly swipe one of the fine stones down the length of the blade to see where the marker is removed. If the stone is removing the marker from the edge along the straight portion but then dipping down into the shoulder toward the tip, you know you need to reposition the knife with the tip closer to the clamp. If the opposite happens - that the stone removes the marker at the shoulder of the bevel along the straight portion and then moves to the edge along the curve, then you need to reposition the knife with the tip further from the clamp. Once you find the sweet spot, measure your knife's position using the alignment guide and record the settings on the chart for future touch-ups.
The technique above will give you a consistent bevel throughout the length of the blade. For certain applications, you might want to position your knife differently so that you have either a more acute or more obtuse angle along the belly and out toward the tip. Below are some examples:
- Chef's Knife - I prefer to have the angle along the belly and out to the tip to be more acute so that it is sharper for slicing and detail work. I like the straight portion, especially at the heel to be a little more obtuse to better stand up to chopping.
- Tactical / Utility Knife - I prefer a more obtuse belly and tip for greater strength in cutting hard materials and thrusting.
- Boning / Fillet Knives - I like the belly and tip more obtuse for greater strength due to the constant contact of the belly and tip with bones.
To create a more acute edge along the belly and out to the tip, position the knife with the tip farther away from the clamp. To create a more obtuse edge along the belly and out to the tip, position the knife with the tip closer to the clamp.
*Even though the angle is remaining constant throughout the curve of the blade, you might experience a wider bevel toward the tip of the knife due to the way the knife is ground. As the belly of the blade curves toward the spine of the knife, the edge is often cut from thicker stock resulting in a wider bevel. An 1/8" thick blade with a 22° per side angle will have much smaller bevels than a 1/4" blade with the same 22° angles. On knives where the tip is inline with the spine and where there is not a distal taper, the effect is more pronounced. A wider bevel in this circumstance is a purely cosmetic concern since the angle is constant.