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Ali Hamza
Ali Hamza
Mechanical
18 Jan 2019

What is seasoning of Timber??

Seasoning of Timber :

Timber cut from freshly felled trees is too wet for normal use and is dimensionally unsuitable. The strength, stiffness and dimensional stability of wood are related to its moisture content. Hence, if wood is dried (seasoned) before use, not only can higher strength values be used in a design, but a more durable structure will result. 

Seasoning is the process of reducing  content (drying) of timber in order to prevent the timber from possible fermentation and making it suitable for use. It can also be defined as the process of drying the wood to a moisture content approximately equal to the average humidity of the surroundings, where it is to be permanently fixed. Very rapid seasoning after removal of bark should be avoided since it causes case hardening and thus increases resistance to penetration of preservatives.

Timber must be stacked, supported and sometimes restrained so  as to minimize distortion during seasoning. If drying is too rapid,  the outer parts, in particular the unprotected ends, shrink before  the interior does, and this leads to surface checking and splitting,  as well as the possible extension of ring and heart shakes. Some  timber species are more difficult to season satisfactorily than  others. 

Some of the objects of seasoning wood are as follows:

1. Reduce the shrinkage and warping after placement in  structure. 

2. Increase strength, durability and workability.

3. Reduce its tendency to split and decay.

4. Make it suitable for painting.

5. Reduce its weight.