Clear & Descriptive (Best for a short summary) A quick guide to sandpaper grits. 1000 grit is significantly finer than 400 grit. Learn what each is used for in sharpening, woodworking, and metalwork. 400 grit is for material removal and shaping. 1000 grit is for refining and polishing. This explains the key differences and applications. https://knivesarea.com/best-ceramic-honing-steel/