A flat whetstone is essential for maintaining a consistent sharpening angle and an even knife edge. This six-step guide explains how to secure the whetstone, mark its surface with a pencil grid, wet the stones and use a diamond flattening plate with controlled movements. Continue until all pencil marks disappear, then rinse both surfaces thoroughly. Regular flattening prevents hollow areas, uneven bevels and inaccurate sharpening from developing over time.
A perfectly flat sharpening stone is essential for maintaining your knives. When your stone is completely level, it guarantees your blade maintains a consistent sharpening angle from heel to tip. If the stone is dished or uneven, it changes the angle of the edge mid-stroke, leading to dull spots, uneven bevels, and eventually a warped blade profile.
To fix a dipped stone, here is the quick breakdown on how to level it using a diamond truing stone:
1️⃣ Secure the whetstone you wish to flatten with a stone holder.
2️⃣ Place the diamond stone (that will act as the truing stone) on top of the whetstone.
3️⃣ We recommend lightly drawing a grid on the whetstone with a ballpoint pen or a pencil (do not use markers; those can be absorbed into the surface of the stone).
4️⃣ Use circular and up-and-down movements to begin the flattening process.
5️⃣ When the grid is no longer visible, the stone is flattened.
6️⃣ Thoroughly rinse both stones to remove any excess material.
Flattening whetstones to up to #5000 grit will get you good results even if you only use a diamond stone. For higher granulations, we recommend finishing with a dressing stone to achieve a smoother/finer surface.
Browse our collection of flattening stones.
