Sawing yield

Posting of the log is a geometric method with the aim to get the maximum volume of sawn products from stock. The result, called sawing yield is greater for coarse than for thin logs.

The decomposition speaks of the center yield and lateral yield depending on what part of the tribe that is sawn. Center yield comes from the tribe's central part and is generally taken as plank with thickness from 38 to 63 mm. Only in exceptional cases is cut thicker planks. Centre exchange characterized by high proportion of core and normal knottiness. Redwood logs are used for joinery timber, such as timber windows. Whitewood logs are used it to lumber, construction timber and plank position. Side yield comes from the tribal peripheral parts and sawn into planks in thickness from 19 to 32 mm.

It is not certain that the maximum sawing yield is also optimal from an economic standpoint. The optimal mill output depends on the price and demand for various dimensions and grades of sawn timber. It also depends, in part, the price of round timber.

Posting and sawing

Posting refers to both the determination of the geometric pattern that stocks should be sawn up after and the insertion of blades and blade in block sawing and through sawing - distance setting. There are various posting and sawing patterns.

The posting determines how the log is sawed to make the largest possible volume sawn product out of stock. Sawing the blocks and then sharing commonly are called Lighthouse sawing. It is the most common way to disintegrate the coniferous timber. For specific applications, there are other saw manner, such as cutting and quarter sawing.

Cutting is used almost always sawing hardwood. In some cases, it is also intended for cutting softwood joinery purposes. Cutting is fast while the products are more easy to be warped.

Quarter sawing shared stocks are firstly cut in two perpendicular directions through the marrow and then sawed into incisions in the 45 ° angle against the first cut surfaces. Quarter sawing is relatively expensive because of lower yield and less shrinkage/swelling and is mainly used for nobler aims to cut wood or surfaces where the rings are perpendicular to the boards' flat side. Quarter sawn wood for furniture manufacturing is preferred.

Examples of posting

Examples of posting

Schematic picture of block sawing, which is the most common method of decomposition
Schematic picture of block sawing, which is the most common method of decomposition.
Cutting and sawing block used for specific purposes
Cutting and sawing block used for specific purposes

European Wood (in China)
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Sino-European Wood Center
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