THE PROPERTIES OF THE WOOD

The properties of the WOOD 

Wood properties generally consists of 3 kinds:
1. Physical properties of wood.
Is the condition where determined by internal factors in the structure of the wood. These factors include: the large number of cell wall substances, arrangement and direction of mikrofibril in cells and tissues as well as the chemical composition of cell wall substances.
2. The mechanical properties of the wood.
 It is the ability of wood to hold the charge from the outside, the intent object that is outside of this style tend to change the shape and size of objects.
3. Chemical properties of the wood.
Is the chemical components of wood where each type of wood varies greatly depending on the type of wood.
Properties of non-mechanical wood include: 
moisture content of wood is the content of the water contained in wood expressed in weighty prosen of dry wood furnaces. Moisture content greatly influences on the process of wrinkle flower wood. Wood stated in case of inflates the addition of moisture content of wood, while the wood shrinking process in case of declared reduction of moisture content of the wood. is the content of the water contained in wood expressed in weighty prosen of dry wood furnaces. Moisture content greatly influences on the process of wrinkle flower wood. Wood stated in case of inflates the addition of moisture content of wood, while the wood shrinking process in case of declared reduction of moisture content of the wood.
Water in wood: 
wood Properties against water is sorbsi in addition to this wood have hygroscopic, consisting of:
a. Adsorbsi (absorb)
b. Desorbsi (yawn)
Great his little water is absorbed by the wood is affected by: 
a. the extent of the wood surface.
b. the temperature and humidity in the atmosphere.
c. air pressure in the air.
d. the chemical composition of the wood.
Of the four most important of these factors is the surface area of the wood.
The water in the wood is split into two: a. non-water (water that is contained in the cell cavities) b. bound Water (water that is found in the cell wall) wood moisture content Calculation Formula:
 Ka (%) = Wb-O x 100%
                    Wo
Description: Ka = water content.
WB = weight clean.
Wo = dry weight.
A tool to measure the moisture content of wood called: muisture metres.
 
Moisture content of wood can be divided into four kinds: 
 1. maximum moisture content.
The condition of the wood where the cell wall or cavity of the cell filled with water.
2. Water Levels balanced.
When a piece of wood placed at certain humidity then gradually will achieve a moisture content that is still called the moisture balance.
3. Moisture content.
Almost the same as the maximum moisture content of the wood, however, will never dry the According to condition.
4. Moisture balanced State.
Wood moisture content conditions that follow.
Moisture content of wood affects the wrinkle flower wood that is to say: the wood is said to be inflated in case of addition of water content, while said to be shrunk when wood moisture content decreased.
Wood has three directions: 
a. Radial (thickness): big depreciation schedule = 4-8%.
b. the Tangential (width): big depreciation schedule = 8-14%.
c. Longitudinal (length): big depreciation schedule = 0.1-0.2%.

To avoid the occurrence of wood shrinkage process is then used to do before drying the wood first.