1. Hold the planer with both hands and press down. Grind the planer into a 40-degree section with the rough surface on the opposite side of the grindstone.

2. Pull back and forth, and the planer and grindstone form a 30-degree angle. Secondly, grind it roughly first, then grind it in a place with strong light until you see a little cutting edge on the blade, and then use a fine grinding stone mill. If you look closely, you will know that there is no sand hole in the blade.

3, or a few scratches on your hand, feeling Mao Mao means success. If you feel slippery, you must grind it again. Then turn off the lights slowly with the reverse side. In the process of grinding, the force must be uniform, and after 2 times, add some water to grind.