Scary sharp is a method of sharpening

Sharpening

Sharpening is the process of creating or refining a sharp edge of appropriate shape on a tool or implement designed for cutting. Sharpening is done by grinding away material on the implement with an abrasive substance harder than the material of the implement, followed sometimes by processes to...

 woodworking

Woodworking

Woodworking is the process of building, making or carving something using wood.-History:Along with stone, mud, and animal parts, wood was one of the first materials worked by early humans. Microwear analysis of the Mousterian stone tools used by the Neanderthals show that many were used to work wood...

 tools with sandpaper

Sandpaper

Sandpaper, also known as glasspaper, is a heavy paper with abrasive material attached to its surface.Sandpaper is part of the "coated abrasives" family of abrasive products. It is used to remove small amounts of material from surfaces, either to make them smoother , to remove a layer of material...

 instead of conventional methods of oilstone or waterstone

Sharpening stone

Sharpening stones, water stones or whetstones are used to grind and hone the edges of steel tools and implements. Examples of items that may be sharpened with a sharpening stone include scissors, scythes, knives, razors and tools such as chisels, hand scrapers and plane blades...

sharpening. The sandpaper referred-to here can be any abrasive impregnated sheet used in the various industries to smooth surfaces and examples include glass paper, silicon carbide, emery cloth, etc. The sandpaper is affixed to another hard, flat substrate to create the sharpening surface. Sheet-glass is commonly used, but a machinist's granite surfacing block, marble baking slabs, plywood, medium-density fibreboard (MDF)or even jointer out-feed tables will produce satisfactory results. The method of fixation is usually a matter of the user's preference, and can include plain water (by means of surface tension), sprayed-on adhesive, or by simply using adhesive-backed abrasive paper.
The basics of the method involves holding the cutting area of the chisel or plane iron flat to the sandpaper and gently moving back and forth in either side to side or back to front motions, as one would with a sharpening stone. The blade is taken through a series of increasingly finer grades of sandpaper.

Advantages

The most notable advantage of the scary sharp system is speed and cost. Anyone with access to sandpaper and a reasonably flat surface can sharpen any cutting tool, often with good results. Unlike traditional stones, no maintenance is required for the scary-sharp set-up, since the sharpening surface does not form a hollow with repeated, uneven usage. A hollowed surface is undesirable in most sharpening situations, an example being the flat surface required in the back (as opposed to the beveled surface) of most woodworking plane irons. Compared to stones, sandpaper is lower in cost as well. A fresh sheet of sandpaper often cuts significantly faster than a bench sharpening stone. For this reason, coarse-grit papers can be used to dress damaged cutting edge quickly, removing chips along the edge and preparing it for the next stage/grit of edge refinement.

Disadvantages

The blade is assumed to be well shaped, with a clean accurate bevel. The back of the chisel is also flattened and cleaned up using the same grades of sandpaper to ensure a clean sharp edge where the back and bevel meet. Nicks, deep scratches, or excessive wear call for shaping the profile on a low speed grinder before beginning the method.

External links

• Early Usenet rec.woodworking posting on Scary Sharp (1995)
• another instance of the same, with commentary and condensed version
• Article on the technique in Fine Woodworking Magazine (2000)
• Sandpaper sharpening demonstration video