Sanding is one of the most essential operations in DIY work. But to obtain a smooth surface, without any roughness, it is still necessary to know choose the right sandpaper. We tell you everything.
What is sandpaper or abrasive paper?
Sandpaper or abrasive paper is a product composed of a hard material reduced to micro-fragments and fixed on a support which is used to polish the surface of a material in order to be able to glue it, paint it or assemble it. Historically, the first prototypes of abrasive paper date back to the 12th century, in China.
At the time, they were in the form of a parchment made up of sand, seeds or shell fragments. The version of sandpaper that we know today was for its part developed from 1833 by the London company of John Oakey who created the techniques of bonding and manufacturing.
The different kinds of sandpaper
There are basically three main categories of sandpaper. At first, we find the flint which is at the origin of the famous “sandpaper”. It is generally used in the manual polishing of raw wood. Then comes the corundum on canvas or on paper which is a crystallized aluminum oxide dedicated to sanding old paintings or very hard woods. Mastics, varnishes or paints will not resist this material which can also be declined in a synthetic version, appreciated for its high resistance capacity. In principle, corundum is used by machine but is also suitable for manual sanding. Last but not least: emery cloth which is suitable for metals, curved or complex surfaces. It has the advantage of not fearing intensive use.
It is important to specify that the nature of the support on which the abrasive is fixed must correspond to the work to be carried out. Traditional and manual operations are done with a paper backing, while machine work requires the use of a canvas backing that resists tearing and overheating. In terms of format, abrasive paper is available in sheets, discs (mainly reserved for machines), rolls or strips.
What to use in DIY?
On dry, flat surfaces, sandpaper finds its application in various DIY jobs. It is used to carry out a roughing which relates to the preparation of a particularly rough and damaged support.
The abrasive is also essential in stripping. This operation consists of removing old traces of glue, paint or rust on a material. Finally, this material makes it possible to carry out finishing work in order to obtain a surface completely free of asperities.
How to choose the right sandpaper for the right rendering?
The choice of sandpaper is mainly made according to the type of sanding to be carried out. The key element to consider is certainly the grain size. Namely that this determines the roughness of an abrasive. The higher the grain size, the more aggressive the abrasive. The size can range from 16 for the biggest to 400 for the thinnest.
Thus, to work very dirty and rough surfaces with a lot of scratches and shocks for example, an extra-coarse abrasive (16 to 40) will be required. If the imperfections are less and the surface is delicate, a medium paper (80 to 100) will suffice. Finally, if it is a question of ginning, an extra-fine model (280 to 400) will do the trick.
A good choice of sandpaper contributes to achieving a beautiful effect on the material. In order to better control the work, starting with a strong grit and ending with a fine grit is an additional tip that should not be overlooked.