History of Sandpaper

History of Sandpaper

Although Isaac Fisher JR. patented the first process for mass manufacturing of sandpaper in the United States in 1834, sandpaper was used as far back as the 13th century in China. Sandpaper paper was made out of crushed shells, seeds, sand, and gum. Originally Sandpaper was known as glass paper, because particles of glass was used. Glass paper (Sandpaper) was being manufactured by John Oakey's company in London by 1833, who had developed new adhesive techniques and processes that could be mass-produced. Since then sandpaper has been made in many different ways. In 1916-sandpaper manufacturer 3M invented an abrasive, which was applied for automotive sanding and refinishing. As a result to the success sandpaper had on refinishing automotive materials, many different abrasive products have been introduced for all types of sanding. Abrasives are now used for wood sanding, metal sanding, glass sanding, automotive sanding and much more. Sandpaper by definition is a “paper, which has abrasives material ingrained into it – part of the “coated abrasive family of abrasive products”.
What is Sandpaper?Sandpaper is a form of paper where an abrasive material has been fixed to its surface; it 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).

Abrasives Backing;
In addition to paper, backing for sandpaper includes cloth (cotton, polyester, rayon), PET film, and "Fibre". Cloth backing is used for sanding discs and belts, while mylar is used with extremely fine grits. Fibre or vulcanized fibre is a strong backing material consisting of many layers of impregnated paper made from rags. The weight of the backing is usually designated by a letter. For paper, the letters range from A to F, with A being the lightest and F the heaviest. Letter nomenclature is different for cloth, with the weight of the backing being, from lightest to heaviest: J, X, Y , T and M. Flexible backing is used if it is necessary to follow irregular rounded contours of the workpiece, otherwise relatively inflexible backing should be used for regular rounded or plane surfaces. Backing of sandpaper may be either glued to the paper or form a separate support for the moving sandpaper as in a belt sander.
What is sandpaper grit?Sandpaper grit is the courser or smoother a particular sandpaper product might be. For example: the lower the grit, the more course the sandpaper is. The higher the grit, the more smooth the sandpaper is.
Sandpaper Types and Grits.Sandpaper is available in sheets, belts, discs, disks, hook and loop, rolls, or adhesive. Sheets, usually come in 9 x 11 size however, many other sizes may be available. Belts can come in many different sizes, as they can be used for portable belt sanders, or they can be used for industrial sanding machines. Sandpaper disks are usually made to fit different types of orbital sanders. Common sizes for sanding discs (disks) are 3” 5” 6” or even 8”. Discs usually come with adhesive, plain, or hook and loop backs. Adhesive back sandpaper discs are for the orbital sanders which require adhesive sandpaper. Hook and Loop is for the sanders which require the velco back sandpaper. Rolls usually come in adhesive backs and are simply rolled up in a roll so that they can be pulled like toilet paper. Other types of rolls are continuous rolls which are usually for airfile, or longboard sanding. Sandpaper grits vary depending on the particular project the sandpaper is being used for. The lesser the grit the more course the sandpaper may be. Common sandpaper grits are 40 grit, 60 grit, 80 grit, 100 grit, 120 grit, 180 grit, 220 grit, 320 grit, 400 grit, 600 grit, 800 grit, 1000 grit, 1200 grit, 1500 grit, 2000 grit, and much more.

Sandpaper Materials;
Sandpaper 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, Used in both coated abrasives, as well as in bonded abrasives.
Also, sandpaper may be "stearated" where a dry lubricant is loaded to the abrasive. Stearated papers are useful in sanding coats of finish and paint as the stearate "soap" prevents clogging and increases the useful life of the sandpaper. Aluminium Oxide with stearate is also known as PS33.

Bonds;
Different adhesives are used to bond the abrasive to the paper. Hide glue is still used, but this paper often cannot withstand the heat generated when machine sanding and is not waterproof. Waterproof or wet/dry sandpapers use a resin bond and a waterproof backing.
Sandpapers can also be open coat, where the particles are separated from each other and the sandpaper is more flexible. This helps prevent clogging of the sandpaper. The wet and dry sandpaper is best used when wet and when using material like acrylic where it leaves a nice smooth feel afterwards.

Shapes;
Sandpaper comes in a number of different shapes and sizes.
Sandpaper sheets — usually 9 by 11 inches, but other sizes may be available
Sanding belts — usually cloth backed, comes in different sizes to fit different belt sanders.
Sanding disks — made to fit different models of disc and random orbit sanders. May be perforated for some models of sanders. Attachment includes Pressure sensitive adhesive (PSA) and "hook-and-loop" (similar to velcro).

Sandpaper rolls -
What is aluminum oxide sandpaper?Aluminum oxide sandpaper is most commonly used for wood sanding. It exhibits a high degree of friability and as a result, heat and pressure is applied. The benefit to the user is that it creates sharp edges and lasts longer than other types of sandpaper.

Health and Safety;
Health and Safety should always an important consideration when sanding. Because the sanding process turns the product you are sanding into tiny particles, wearing dust masks might prevent problems associated with sanding. The dust mask will help provide protection from annoying and potentially harmful substances such as, sawdust, metal dust, glass dust, plastic, and much more. By wearing safety goggles, much other health related products might be prevented. AbrasivesOasis recommends that if you are sanding metal and sparks are created, you should wear cotton (not polyester) fabrics. Additionally you should wear safety gloves to protect your hands.