What Is an Oil Stone?
An oil stone is a stone that is soaked in oil to be used for grinding metals and other materials.
The whetstone used in ordinary households is a water whetstone, which is used to grind kitchen knives by dipping them in water. Unlike water whetstone, oil whetstone is used to grind knives and other metals with oil.
In recent years, synthetic oils specially designed for oil stone have been sold, but in the past, kerosene was used for grinding.
Uses of Oil Stones
Oil stones are still commonly used in the United States and other countries in recent years.
In the Middle East and inland areas of the United States, water is more expensive than oil. Therefore, oil stones, which can sharpen knives without the use of water, have become the mainstream.
Oil stones are generally used in industrial applications because they are harder than water stones and wear less easily.
Principle of Oil Stones
Since oil is more lubricious than water, oil stones are made of hard, rough materials.
Water stones are made up of a collection of hard minerals, the same as oil stones. For metals with a rough surface finish, use a coarse-grained grindstone, and for finer-grained surfaces, use a fine-grained grindstone. However, the finer the grain size, the shorter the life of the wheel. Therefore, the wheel should be selected according to the required surface roughness.
There are also standards for the grain size of oil stones, which are numbered according to the average grain size. The rougher the grain size, the smaller the number, and the finer the grain size, the larger the number.
Oil stones come in a variety of shapes. The most commonly used shape is rectangular, but there are also paper-shaped grinding stones similar to sandpaper and cylindrical grinding stones.