Abrasives

An abrasive is a material, often a mineral, that is used to shape or finish a piece of material through rubbing which leads to part of the work being worn away.

The main abrasive we use in Clounagh is sandpaper, emery paper and wet and dry emery paper.

Sandpaper is a form of paper where an abrasive material has been fixed 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 (painting and wood finishing), to remove a layer of material (e.g. old paint), or sometimes to make the surface rougher (e.g. as a preparation to gluing). When the planning has been done it is a good idea to use the sandpaper wrapped around a cork block to give a final smoothness to the wood prior to varnishing.

You used this type of abrasive to smooth the wooden part.

Emery paper is a type of paper that can be used for sanding down hard and rough surfaces. It can also be used for resistant technology purposes to give a smooth, shiny finish to manufactured products and is often used in the finishing of high-end watch movements. Similar to sandpaper, it is made by gluing small particles of the mineral emery to paper.

You used this type of abrasive to give a final smooth to the plastic before using the polishing machine.

Emery paper can also be used on metal.

Other Material as an abrasive.

Materials used for the abrading particles are:

• flint — no longer commonly used

• garnet — commonly used in woodworking

• emery — commonly used to abrade or polish metal

• aluminium oxide — perhaps most common in widest variety of grits; can be used on metal (i.e. body shops) or wood

• silicon carbide — available in very coarse grits all the way through to microgrits, common in wet applications

• alumina-zirconia — (an aluminium oxide – zirconium oxide alloy), used for machine grinding applications

• chromium oxide — used in extremely fine micron grit (micrometre level) papers

• ceramic aluminum oxide — used in high pressure applications, commonly known as CubitronTM a 3M Corp.