What is an oilstone whetstone?

What is an oilstone whetstone?

Oilstone is  a kind of rock rich in oil. There are generally six types of materials: green silicon carbide, white corundum, brown corundum, boron carbide, ruby (also known as sintered corundum) and natural jade.


Oilstone is a sintered natural mineral. "oilstone" is originally black or brownish-black, while those exposed on the ground are grayish white due to weathering. The surface does not look like oil, but when it is distilled with hot gas, the organic matter in it decomposes into kerosene, hence the name. Its texture is fine and tough, and can be used as an abrasive tool. Later, the strip-shaped consolidated abrasive tools made of abrasives and bonding agents were also called whetstones.


The Features 

Oilstone is similar to coal, kerosene, and bitumen because it is made of organic matter accumulated by ancient animals and plants. The accumulation of its beds is always in shallow coastal waters, which are rich in inferior organic plants, scales, insects and other deformed animals that are difficult to identify. The structure is very fine, with lime and sand inside, and the texture is tough. It is a kind of delicate rock, used to sharpen tools and other metal surfaces.

Industrial application

Ruby oilstone: It is a kind of microcrystalline corundum product that is sintered at high temperature. It has a compact and delicate structure, and has high hardness and strength.
The product is rose red, and the products are divided into three categories: small grinding wheel type whetstone, standard type whetstone, and grinding head type whetstone. When grinding a workpiece, it can maintain a sharp edge and a stable geometry for a long time.
It is suitable for forming and grinding of instrument industry, precision parts, micro tools, tools, precision abrasives, etc. The processing precision and surface roughness can reach about 0.05μm.
Product specifications: small grinding wheel type flat grinding wheel whetstone with a diameter of less than 100, standard type whetstone with various geometric shapes within 200*50*25cm, and grinding head whetstone of various shapes with a grinding head diameter of less than 25cm.

The oilstone classification

Diamond oilstone
It has the advantages of good elasticity, cutting force, wear resistance, etc. It is difficult to reach for mold manufacturing, tool repair, various workpiece bends, holes and ordinary abrasive tools. It is an ideal abrasive tool and other oilstone Irreplaceable.

The specifications are 100*2-10*0.5-1.2, and the grits is 320#-1200#

Ordinary oilstone
Widely used in machinery manufacturing, mold manufacturing, instrumentation and other fields

Super fine grinding oilstone
Super fine grinding stone and powerful grinding stone are widely used in machinery manufacturing, mold manufacturing, instrumentation and other fields. Ergonomics is twice that of ordinary oilstone

Ruby oilstone
Ruby is a kind of corundum microcrystals made from alumina powder and sintered at high temperature. The structure is compact and delicate, with high hardness and strength. Because it is a sintered product, it has no characteristics such as various hardness grades, particle sizes and different strength ranges, but it has a dense structure and a pore structure. Therefore, the product is marked with a structure and the product is rose red.

Boron Carbide oilstone
Boron carbide is a hard black shiny crystal. Hardness is lower than industrial diamond, but higher than silicon carbide. Whetstone particle size is between 400 and 1000, the smaller the particle size, the rougher, the greater the amount of grinding, used for the grinding of semi-finished tools. Because of its strong hardness, it is particularly wear-resistant and not easy to scratch.

Grinding method

Diamond paste, the particle size ranges from W40 to W0.5. W40 is the coarsest and has a large amount of grinding, and W0.5 is the finest. It is used for polishing, and even harder knives can be ground without annealing.

Coating coarse W40 grinding paste on the boron carbide whetstone can speed up the increase of the grinding amount without annealing.
Then, after cleaning the rough abrasive paste on the knife, apply W0.5 abrasive paste to ruby or natural jade for polishing. The result is a mirror surface.

The three types of green silicon carbide, white corundum, and brown corundum are not hard enough. In addition, the grain size is a bit coarse, which makes it easy to grind the knife. Moreover, the other three types of whetstone will not be annealed during polishing and grinding.
There is no difference if the particle size is greater than 1000. It is mainly determined by the abrasive paste used. Apply the W1.5 abrasive paste on the ruby of 1000 mesh, and its abrasive effect is the effect of the W1.5 abrasive paste, which is 2500 grit. Whetstone effect.

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