Sharpening a new chisel
When sharpening a new chisel you are going to need to flatten the face before you sharpen the bevel. This is done by lubricating an extra coarse diamond bench stone (Diamond Whetstone™, Duo-Sharp® & Dia-Sharp® models available) with water and placing the back of the chisel down on the sharpener.
Push downward on the face and move the chisel from one end of the diamond stone to the other with long fluid strokes (see illustration below).
Next, use the coarse grit stone and step down through the grits, ending with extra fine. Use the same procedure as with the extra coarse stone.
After all the diamond grits have been utilised, you can step down into the Dia-Paste™ diamond compound to achieve a mirror finish.
Sharpening the bevel
Now we're ready to sharpen the bevel of the chisel. Put your thumbs under the blade and your fingers on top (see the video below for an illustration of this). Using your hands in this fashion gives you a makeshift jig.
Make long fluid strokes back and forth, pushing the blade downward onto the stone. Use a fine grit diamond sharpening stone unless the blade is very dull or chipped, in which case start with a coarse grit.
Adding a micro bevel
After sharpening the bevel you may want to put a micro bevel on the end of the blade. This is done by holding the chisel in the same manner and matching the bevel to an extra fine stone. Now lift the chisel up a small amount to an angle of about 1 or 2 degrees greater than the bevel. Only a few strokes and you have a sharp micro bevel.
Finally, lay the face down flat again and give two quick strokes to take the wire burr off the bevel edge.