Check the progress in raking light: Hold the blade angled away from you and twist it in the light. You will be able to see your new coarse scratches from the old surface finish.

Don’t change grits until you are certain the back is completely flat. Changing grits too soon will just make you come back to the coarse one and you will have wasted the work at the next stone.

Don’t get to discouraged, this chisel took me about 40 minutes to get through the first grit... but I will never have to do it again. Rinse the blade and stone between grits to prevent transfer.

Once you are ready to change grits do a dozen or so passes with the blade turned 90° to what you have been doing. This will give you a scratch pattern that will show through when you are working on the next grit.

The second grit should go fast: all you are trying to accomplish is complete removal of the scratches from the coarser grit. Always finish with some scratch marks at 90°, it’s quick and easy from here out!

Take it out to the finest grit you have available: The more polished the edge is the sharper it will be and the better it will be at retaining that edge. Once you hit about 8000 grit there are few gains to be made.

Photos: Progressing through flattening the back of a 1/2" chisel.