Editing Pencil sharpener (section)

=== Linear blade sharpeners ===
[[File:Temperowka.na.zyletke.jpg|thumb|A linear sharpener that uses a [[razor|razor blade]]]]
Unlike prism sharpeners, linear blade sharpeners do not rotate relative to the pencil being sharpened, and may be viewed as just a special form of knife, with a mechanical guide for increased safety and convenience. Some models use replaceable shaving [[razor blade]]s, while others have permanently-fitted blades. Linear blade sharpeners may require more skill, but they allow one to sharpen the tip of the pencil into any desired shape and angle of taper, whereas prism sharpeners have a fixed sharpening angle and produce circular symmetry.

While most linear blade sharpeners are simple and directly hand-operated, some devices in the past were crank-operated, using mechanisms to convert crank rotation into linear motion.<ref name="officemuseum">{{cite web |url=http://www.officemuseum.com/pencil_sharpeners.htm |title=Pencil Sharpeners|access-date=9 July 2011}}</ref>