Automatic Knife Sharpener provides a precise, efficient and safe method for honing Microtome Knives upto 140mm in length, equipped with automatic timer 0-60 min. to adjust sharpening time. It ensure a knife edge so perfect that no subsequent strooping is necessary. The knife edge is recodtioned to optimum sharpness which is so major importance to every laboratory, where material are routinely sectioned for microscopic examinations. The transparent plexi glass cover encloses the entire working mechanism and provides a safe dust and gritfree sharpening process. The knife strokes against a high frequency glass honing plate and after three exactly equivalent strokes on one side of knife edge, a cam follower automatically flips the knife and three strokes are honed on other side.