This Shapton Naoru Cast Iron Lapping System is made to clean and lap your sharpening stones. Designed for Shapton, but can also easily be used on other sharpening stones. The set is comprised of a cast-iron lapping stone two bottles of lapping powder (silicon carbide grains): coarse and medium.
Even if you use the best sharpening stones in the world, if they are not completely flat you won't be able to use them to their full extent. It is therefore important to lap them. Leave that to this Shapton Naoru. The lapping stone is heavy, hard and nicely sized (25 x 10 cm). It is enhanced with grooves with a crystal structure. These grooves increase the synergy between the lapping stone and the silicon carbide grains and help you get rid of the sharpening slurry to make sure the stone can do what it is supposed to.
The Shapton Cast Iron Lapping System comes with two bottles of silicon carbide grains. One contains coarser grains, made to lap Shapton stones with a grain size between 120 and 320. The other bottle contains medium grains, to lap Shapton sharpening stones with grain size 1.000 to 4.000. Do you also want to lap stones with grain sizes ranging from 5000 and up? Use the bottle with fine grains. This is sold separately
How to use the Shapton Naoru Lapping System
Place the lapping stone on a stable surface. Pour water over the stone and allow the water to reach the corners. Pour the silicon carbide grains over the stone and divide them evenly. Now you can start lapping your stone.
Before you start you need to use a pencil to draw a grid on your sharpening stone. This helps you determine how long you need to flatten your stone. As such you don't remove too much stone.
You place your stone on your lapping stone and move it from corner to corner. Because of this diagonal movement you use the surface to its full extent, making sure that the sharpening stone is evenly lapped. You also make sure the dirt is immediately removed. As such it will be as good as new afterwards! Add water and additional grains if need be during use. Done lapping your stone? Clean both the lapping stone and the sharpening stone to make sure you won't be bothered by scratches.