How to sharpen a knife?

 3.   Using TWIN® Stone Pro and TWIN® Finishing Stone Pro

TWIN® Stone Pro

HOW TO USE TWIN® Stone Pro:

Preparation:

1. Set the whetstone into the bottom case with the gray side up. The gray side is for rough sharpening and the lighter side for fine sharpening.
2. Only fine sharpen the blade with the blue side after it has been roughly sharpened with the gray side.
3. Place the stone into the transparent bottom case. Then place the case on a flat, dry surface. The rubber feet on the bottom of the case will prevent slipping.
4. Apply a small amount of water on the surface of the stone. Completely soaking it in water is not necessary.
5. Make sure to keep the stone wet while sharpening.
6. A gray liquid will develop while sharpening. Do not wash this liquid away as it is necessary for a smooth sharpening.
7. After sharpening is complete, rinse the liquid from the surface and dry off the stone completely. Keep it in a cool and dry place away from direct sunlight.

HOW TO SHARPEN A KNIFE with TWIN® Stone Pro

FOR A DOUBLE-EDGED KNIFE:
1. Begin sharpening on the coarse (gray) side.
2. Set the blade with the cutting edge faced toward you at an angle of 45 degrees to the length of the stone. The back of the blade should be kept at 10 to 20 degrees (similar to a pile of 3 coins) from the surface of the stone.
3. Place the fingers of one hand lightly on the center of the blade. While maintaining the angle, sharpen the blade by moving it back and forth using even strokes.
4. Sharpen the tip, center and then heel of the blade until a burr appears on the cutting edge.
5. Once a burr appears, turn the knife over and sharpen the other side in the same manner.
6. Turn the stone over to the fine (blue) side and repeat steps 2. - 5. Please be aware that it is difficult to feel the burr when sharpening on the fine side. Therefore, sharpen the knife until it has reached the desired level of sharpness.
7. As a final touch, sharpen the edge a few times in a diagonal direction lightly enough to remove any remaining burrs.
8. After sharpening, remove the grinding paste by washing the knife under the tap and dry it carefully with a towel.
9. A properly sharpened cutting edge should have a shiny finish and cut thin paper smoothly.

FOR KNIVES WITH A ONE-SIDED EDGE:
1. Only one side of the cutting edge needs to be sharpened, in the same manner as described above.
2. As the burr needs to be removed with one-sided edges too, turn the knife over once a burr appears, but move the knife back and forth on tip, center and heel on the non-edge side a few times only.

MAINTENANCE

When the stone is worn out or becomes concave, use coarse waterproof sandpaper to even out the surface by sanding it down. You can also use a touch-up stone to flatten the surface. Click here to view TWIN® Stone Pro

TWIN® Finishing Stone Pro

TWIN® Finishing Stone Pro is the perfect complement to TWIN® Stone Pro for your knife sharpening needs. TWIN® Finishing Stone Pro itself is not suitable for sharpening a knife. It has an extremely fine grit (#3000 / 8000), and is used AFTER sharpening your knives on stone with medium grit.  The result: knives with an extremely fine, razor sharp, mirror-finish cutting edge. Click here to view TWIN® Finishing Stone Pro

TWIN Finishing Stone Pro is NOT a sharpening stone. Any nicks or irregularities on the edge must be smoothed first with the TWIN Stone Pro.  However, if your knife blade has recently been sharpened and still retains a good cutting edge, the TWIN Finishing Stone Pro can be used on its own to refine the edge.

HOW TO USE TWIN FINISHING STONE PRO:
 
PREPARATION

1. For fine finishing, place the whetstone into the bottom case with the light grey side up.  Never use the white side first.  Extra fine finishing should only be done after the fine finishing has been completed.
2. For extra fine finishing, place the stone into the transparent case with the white side up.
3. Place the case on a flat, dry surface. The rubber feet on the bottom of the case will prevent slipping.
4. Apply a small amount of water on the surface of the stone. Completely soaking it in water is not necessary.
5. Make sure to keep the stone wet while in use.
6. A grey liquid will develop while sharpening.  Do not wash this liquid away as it is an integral part of the process. 
7. After finishing is complete, rinse the liquid from the surface and dry off the stone completely. Keep it in a cool and dry place away from direct sunlight.

HOW TO FINISH A DOUBLE-EDGED KNIFE

For a double-edged knife
1. Prepare the whetstone according to the directions above with the light grey side up.
2. Grip the knife handle with one hand and set the blade on the whetstone with the cutting edge faced toward you at an angle of 45 degrees to the vertical axis of the stone. The back of the blade should be kept at 10 to 20 degrees from the surface of the stone.
3. Place the fingers of your free hand lightly on the center of the blade, but take care not to touch the cutting edge. While maintaining the angle, move the blade back and forth the length of the whetstone using even strokes.
4. Polish the tip, center and then heel of the blade with 5-10 strokes in each respective area.  Longer or shorter blades require more or less sections.  Always polish from tip to heel.
5. When one side is completed, turn the balde over and repeat steps 1-4.
6. When both sides are properly finished, wipe the knife dry with a dry cloth to remove all the water and test the sharpness with a sheet of paper.  If the paper cut is not smooth after proper finishing, remove any remaining burrs from the edge by laying a towel or cloth on a flat surface and dragging the blade across the cutting edge on either side. Test the sharpness again aand if no satisfactory result has been achieved, repeat steps 1-5 until desired sharpness is achieved.
7. If a sharper edge and a mirror-polished finish are required, continue with the extra fine finishing surface (white). Repeat steps 2-6.
8. A cutting edge that has been properly finished with the light grey surface should have a moderately shiny finish and a very sharp cutting edge.  A blade finished with the white, extra fine finishing surface should show a brilliant, shiny finish on the cutting edge and cut paper even more smoothly.

For knives with a single-bevel edge
1. Only one side of the cutting edge needs to be sharpened, in the same manner as described above. Follow steps 1-6 above.  Long-bladed knives like the Yanagiba and others need more than three sections to properly finish the entire blade.
2. With single bevel blades, the tapered side is finished first, then the knife is turned over to the straight side and set completely flat on the stone. Move the knife up and down the stone.

MAINTENANCE

When the stone is worn out or becomes concave, use coarse waterproof sandpaper to even out the surface by sanding it down. You can also use a touch-up stone to flatten the surface.

Disclaimer:
Sharpening knives is potentially dangerous. ZWILLING J.A. HENCKELS cannot be held responsible for any possible damages.