Abrasives

Below Coated and bonded abrasives

Pink The same as white, with less than 0.3% chromium, which gives it the pink colour and makes it less friable than white.

Ruby The same as white, with more than 0.3% chromium, which gives it the ruby colour and makes it sharper and less friable than pink.

Blue The same as white but using a blue bond.

White This is 99% pure aluminium oxide. It has sharp grit and is 100% friable.

Pink The same as white, with less than 0.3% chromium, which gives it the pink colour and makes it less friable than white.

Ruby The same as white, with more than 0.3% chromium, which gives it the ruby colour and makes it sharper and less friable than pink.

Blue The same as white but using a blue bond.

Abrasives are sharp grains of various materials that can be used to wear away another material. There is a large selection of materials offering different cutting properties to meet tho wide variety of applications used in industry. They also come in a regular range of sizes, which affects removal rates and surface finish.

Below Coated and bonded abrasives

Aluminium oxide

This is a synthetic mineral (man-made grain), which comes in a number of different forms.

Blue/grey Regular aluminium oxide with 35% titanium oxide. Highly resistant to wear and extremely durable, it is used for high-speed grinding and finishing of metals and other high tensile strength materials without excessive fracturing or shedding. In this respect, grey aluminium oxide will outperform all other bonded abrasive grains.

Brown A lower fired version of blue/grey aluminium oxide.

White This is 99% pure aluminium oxide. It has sharp grit and is 100% friable.

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Ceramic

This is a specially manufactured crystalline abrasive, structured for high stock removal when grinding exotic materials. It Is visually similar to blue/grey aluminium oxide.

Garnet

The garnet used in coated abrasives is Almandite. a reddish-brown mineral of medium hardness. It has good cutting edges, which tend to break or re-fracture in use. forming new cutting edges. It is used as a wood abrasive.

Vegetable

As a complete contrast to the above, vegetable products such as cob husk and walnut shells are used for abrasives, mainly as blast media.

Below A selection of different abrasive grits.

Flint

This mineral is quartz (silicon dioxide) and is white in colour. Finely ground, it has the appearance of white sand and fractures into a sharp-edged grain. It is not a good abrasive, even though it is the abrasive used in common sandpaper.

Emery

Emery is a natural mineral composite ol iron oxide and corundum. It is black in colour and its grains are hard, round and blocky in structure. It cuts slowly and tends to polish the material being abraded: it is used primarily in the automotive industry. There are natural emery mines in Turkey - the only ones in the world.

Silicon carbide

A very friable grain, silicon carbide cuts faster under light pressure than any other grain used in coated abrasives. Dark green high purity is for sharpening tungsten carbide-tipped tools. Black is used wet or dry for sanding between finish coats, especially on metal surfaces. It has flexible, tear-resistant backing. Silver grey is a very hard, sharp, man-made abrasive suited for non-ferrous materials and non-metallic materials, such as concrete, marble and glass.

Zirconium

Zirconium is a very fine, dense, man-made crystalline grain, which can be used for aggressive stock removal. It has a unique self-sharpening characteristic and so has long life on heavy stock removal operations.

Grit

The crude grains are crushed and separated into sizes, called grit sizes, using calibrated screens. The size Is the number of openings per linear inch in a controlled sieving screen, through which the grains fall. Grits range from 12, which is very coarse, through to 1,200. which is very fine.

Below A selection of different abrasive grits.

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Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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