Monday, December 1, 2014

Differences between sandpapers

There are many varieties of sandpaper available on the market today. They come in different grits, sizes, abrasions, materials and backings. Each has its own purpose. Here is a list of the different characteristics and types of sandpapers.

Sandpaper materials – They are responsible for the smoothing and shaping of materials.

  • Ceramic – one of the hardest materials that are used to make sandpaper, they are also the most expensive. They are used to shave and level woods.
  • Garnet – it is made from fine sand particles. It is cheap but less durable. Also primarily used on wood.
  • Silicon Carbide – this type of sandpaper can come in many grits and is very coarse. It is primarily used to cut metals, plastics and fiberglass. It can be used even on wet surfaces.
  • Aluminium Oxide – this is available in all type of grits, making it perfect for general use. Its primary use is for sanding down wood and metals.
  • Chromium (III) oxide – this has an extremely fine grit, measured at micrometre levels.
  • Emery – commonly used to polish metals.


Grit level – this is the abrasive measurement for sandpapers. It is responsible for the coarseness of the sandpaper. The higher number of grits is used for polishing and refining, while sandpaper with a lower number of grits is used for shaping materials. Below is a table of sandpaper grits and their recommended usage.

Size
Grade
Recommended Material(s)
Purpose
30 – 40
Very coarse
Metal and Wood
Shaping, Removing rust
40 – 60
Coarse
Metal and Wood
Removing scratches, shaping and removing paint
60 – 100
Medium
Wood and Plaster
Removing marks or dents, smoothening of walls
100 – 160
Fine
Wood and Plaster
Used before finishing
160 – 220
Very-Fine
Wood and Plaster
Final sanding
220 – 250
Extra-Fine
Wood and Plaster
Final sanding
250 - 400
Extra-Fine
Wood and Plaster
To provide a silky feeling
400 - 800
Super-Fine
Wood, Plaster and Glass
Used for wet-sanding, it provides sheen
800 – 1000
Ultra-Fine
Glass, Car Paint
Primarily used for polishing


Backings – the most common sandpaper backing is made of paper. Other backings include cotton, polyester, rubber, fibre, rayon and mylar. Special backing materials like cloth are used for sandpaper discs, mylars are mainly used for finer grit sandpaper backing. The softer the backing material, the more flexible the sandpaper will be.

Backings are also classified into different weights – ranging from A to F. “A” being the lightest and “F” the heaviest.

Shapes and Forms– there are many sandpaper shapes to suit every application. The common shape is the sheet type.
  • Sheet type – usual size is 230 x 280mm.
  • Rolls.
  • Triangle – specifically made for “palm sanders”.
  • Sponge – used for tight areas.
  • Belt – specifically made for “belt sanders”.
  • Disk – specifically made for “orbit sanders”.

The above information is essential for sanders. If not used properly, sandpaper may do more harm than good.


Sealants Tools & Direct offers a wide array of sandpapers that are available in many forms, sizes and grits. We offer our sandpapers in bundles for maximum savings. For order placements you may reach us on 01626 333360. Alternatively, you may visit our website and use our online order form.