Wood is valuable natural material which was created by nature itself. People have been using this wonderful raw material for many centuries to build houses, create furniture, decorative items interior, and also used for industrial purposes. For these reasons, proper processing of a felled trunk is an extremely important task. Sawing and planing wood are the most important operations with wood. In this article we will talk about what wood sawing is and what types of sawing exist.

Log sawing is the process of converting valuable natural raw materials into lumber. When sawing wood various methods lumber can be obtained in various sizes. To obtain high-quality products, you need to choose high-quality, even logs that are not damaged by pests.

Types of wood cutting

The quality of the final product depends on large number factors - type of wood and quality of raw materials, professionalism of workers, proper drying. However, there is another important aspect - this is the method of cutting timber.

There are the following cutting methods:

• tangential
• radial
• rustic
• longitudinal
• transverse.

Rustic is a cut that is performed under acute angle to the direction of the fibers. This method is used in the production of lumber for rustic flooring, which can be called the most heterogeneous and original in pattern and shade.

During tangential cutting, the cut plane lies tangentially to the annual layers of the material at a certain distance from the core. Since wood fibers are most often located in different directions, a natural pattern in the form of fancy “arches”, “curls”, “rings” is obtained on the surface. The structure of the board with this cutting option is heterogeneous; wood pores may be present. At the end of the tangential cut, the boards are characterized by an increased coefficient of shrinkage and swelling. Also, this log sawing scheme makes it possible to increase the useful yield coefficient, which causes a reduction in the cost of the final product.

Sawing wood blanks using the radial method is carried out perpendicular to the annual rings. Thus, a homogeneous board is obtained with the smallest gaps between annual layers. This creates an attractive pattern and also increases the strength of the lumber. Radial materials are characterized by high resistance to deformation and wear resistance. Also, such boards have lower rates of shrinkage and swelling compared to tangentially cut lumber. Therefore, finished products, for example, parquet board, floorboard, block house, lining, practically do not crack on the front part, but tangential sawing materials are susceptible to such phenomena. Glued laminated timber is created only from radial and semi-radial cut boards, because the mechanical and geometric parameters are directly dependent on the resistance of the fibers. This resistance increases during gluing of layers with multidirectional annual rings at an inclination angle of no more than 45°.

Only 10-15% of radial boards can be obtained from a single log. Therefore they have a high cost. The most best performance demonstrates material having an angle between the growth layers and the cutting plane from 80 to 90 degrees.

Sawing wood across the grain

The technology of sawing wood across the grain is the most common method of processing timber in carpentry. At the same time, such sawing can be called the simplest. Longitudinal sawing wood requires much more effort and certain skills.

Tools for cross-cutting timber are selected depending on the required accuracy, the amount of work and the conditions available in each individual workshop. You can use:

• electric circular saw. She makes neat and fast cuts. For household use, a model with a 1000 W motor and a disk cross-section of 180 mm is perfect. Most circular saws have a combined blade included, which can be used to implement the most various works. The teeth of this blade are something between the teeth of a transverse and longitudinal saw. For long-term work, it is better to take a blade that is coated with carbide. Its cost is higher, but it takes 10 times longer to dull
• miter box and tenon saw. They are used for finishing. These tools can be used to make the most precise cuts.
• circular saw
• cross saw. When purchasing, please note that the teeth of such a tool should be alternately positioned to the left and to the right of the blade itself. They must be well sharpened and beveled. The most popular is a saw with 10 teeth per 25 mm blade. With 8 teeth, the saw will cut faster, but will create rough cuts.

The cut of wood determines the texture of the parquet board and the row performance characteristics. There are 3 main types of cuts: tangential, radial and rustic. Less commonly, mainly for artistic parquet, transverse or, as it is also called, end cutting of wood is used, in which entire growth rings are preserved. In addition, there are mixed cuts - semi-radial and semi-tangential.

The radial cut is made perpendicular to the growth rings, the layers are clearly visible on the die, they are located parallel along the length, the texture of the parquet board is uniform and monochromatic.

Advantages and disadvantages of radial cut

Due to the fact that the process of shrinkage and swelling occurs along the thickness, the coefficient is only 0.18 and 0.2 accordingly: the value is 2 times higher than that of tangential cut wood, which changes dimensions along the width.

Parquet has increased strength characteristics and exceptional stability in various climatic conditions. However, you have to pay for everything: the radial cut yield does not exceed 15%, which significantly increases the cost of lumber.

Tangential cut

The tangential cut runs tangentially to the annual layers, but bypasses the core of the log. The texture is heterogeneous and variegated; natural patterns are created on the dies that convey the uniqueness of the breed.

Pros and cons of tangential cutting

However, with all the originality of the parquet texture less resistant to humidity and temperature changes. Due to the minimal amount of scrap, tangential cut boards are cheaper.

Rustic cut

The cut is made in any direction at an acute angle to the wood fibers: boards are obtained with a wide variety of textures. That is why the rustic cutting method is extremely rarely used in the production of parquet: it is almost impossible to select uniform dies that are comparable in color.

The cutting method determines the texture and color of each die, and also directly affects the stability and strength of the floor covering.

The range of lumber offered is quite wide; woodworking products vary in quality, cost, as well as in the types of wood cut. Let's take a closer look at what types of wood cutting exist, and for this we first look at general outline what exactly is the technology of cutting wood?

Forest cutting

First of all, the log is unraveled on a belt or disk sawmill, turning into a gun carriage. If all sides are sawn, then the output will be edged material, which is divided into timber, small timber and edged boards. Planed patronage is called lining, floorboard, platbands and baseboards. Glued products include, for example, furniture panels.

There are two main types of cutting wood (logs) into boards (lumber):

• radial;
• tangential,

as well as three additional types:

• mixed;
• semi-radial (rustic);
• central.

Types of board cuts

Radial cut- this is a cut in which the axis of the cut passes through the core of the log and, as a result, the lines of annual rings in the section of the board form an angle of 76 - 90 degrees. with its faces (two main planes of the board). The wood of radial cut boards is quite uniform in color and texture. Such boards practically do not deform when dried and do not swell when moistened, because the change in wood dimensions occurs mainly along the line of the rings (across the grain), and for radial cut boards they are located along the thickness. Radial cut lumber has the highest performance indicators compared to lumber of other types of cut.

Tangential cut- This is a cut that is made along tangents to the lines of the annual rings of the trunk at some distance from its core. The surfaces of such boards have a pronounced texture and a bright wave pattern. different pattern annual rings. For tangentially cut boards, the coefficients of shrinkage and swelling due to moisture are twice as high as for radially cut boards, which causes their significant deformation when the humidity state changes. For this reason, tangential cut boards are less preferable for use in wet conditions than radial cut boards.

Rustic (semi-radial) and mixed cuts- these are cuts with signs of two main types of cuts at the same time: radial and tangential and, as a result, have indicators averaged between them. In a rustic cut, the lines of annual rings have the form of straight lines located at angles of 46 - 75 degrees. to the layers, and in a mixed cut these lines change from straight at the edges (along the width) of the board to arched in the middle.

Central cut- This is a cut made directly in the center of the trunk and including its core. Considering that the core of the trunk consists of the least durable wood, center-cut lumber has the most heterogeneous structure in terms of strength of all the types considered.

Features of the main types of cutting

At tangential cutting the cut plane runs tangentially to the annual layers of the tree at some distance from the core. Since wood fibers, as a rule, do not have a single direction, they create natural patterns on the surface of the board in the form of fancy “arches”, “curls”, “rings”. The texture of the resulting tangential cut board is uneven and may contain wood pores. Some of the dry boards may develop delaminations on the surface after finishing planing. After tangential cutting, boards are characterized by higher coefficients of shrinkage and swelling; moreover, such a scheme for sawing logs allows an increase in the useful yield, which in turn leads to a reduction in the cost of the board.
For radial cutting of wood, the cutting plane is located perpendicular to the annual rings. With this method, the texture of the board is quite uniform with a minimum distance between the annual layers. This not only creates a beautiful pattern, but also increases the strength of the lumber.

Boards radial cut have good resistance to external influences, have greater resistance to deformation and wear resistance than tangential cut boards.

The shrinkage and swelling coefficients of radially cut lumber are 0.18% and 0.2%, respectively, which is almost two times better than that of tangentially cut lumber. The reason for this phenomenon is that for radial cut boards, shrinkage and swelling occur along the thickness of the material, in contrast to tangential cut boards, in which dimensional changes occur along the width of the board. This explains the fact that in finished products (parquet boards, floor boards, block houses, imitation timber, lining) made from radially cut lumber, there are almost no gaps on the front surface, which is not excluded in products made from tangentially cut lumber. To obtain laminated veneer lumber by splicing wood without knots, blanks and boards of radial and semi-radial cuts are used, since mechanical and geometric characteristics beams depend on the resistance of the fibers, which increases when gluing layers with multidirectional annual rings with an inclination angle of up to 45°.

The average useful yield of radial cut boards is only 10-15%. This explains their high cost. Radial cutting includes lamellas in which the angle between the annual rings and the blade is 60-90°. If the specified angle is in the range of 45-60°, such boards are classified as semi-radial cut. The best performance properties are found in lumber in which the angle between the annual layers and the cutting plane is 80-90 degrees. Taking into account semi-radial cut boards, the useful yield coefficient can reach 30%.

Typically, when radial sawing, the log is initially sawn into quarters, and then from each quarter, boards are sawn off alternately from two layers. For sawing logs in a radial way, for example, UP-700 longitudinal sawing machines can be used. The microprocessor control and optimization system UP-700 is important, which is used by technologists to determine the percentage of yield of radial cut boards based on the criteria for optimizing the maximum yield finished products, as well as the conditions of radial and semi-radial cutting.

Comparing radial and tangential types of cuts, several conclusions can be drawn:

• Radial lumber has best properties shrinkage and swelling.
• Radial cut boards have better mechanical characteristics and dimensional stability.
• The wood of radial cut boards has a uniform shade and uniform texture, which gives special decorative value finished products made of wood.
• Due to their characteristics, radial boards are more wide application, although they have a higher price.

Main dimensions of lumber

There are standard dimensions of lumber. For example, the cross-section of a beam can be 10x10, 10x15 or 15x15 cm, and the length is 6 m. Deviation from these standards will require a special order and will also be associated with additional financial costs. The most expensive is profiled timber, manufactured to the highest cleanliness class.

The edged board can be 2.5 cm, 4 cm or 5 cm thick, 10 cm, 15 cm wide, and a standard length of 6 m. The length of small timber, in addition to the standard value of 6 m, can also be equal to 3 m Its cross-section will be 4x4 cm or 5x5 cm. A by-product of the production of these lumber is a slab, on one side of which there is a face, and on the opposite side there is untreated wood.

Criteria for choosing lumber

Before you choose good lumber, the first step is to find out the type of wood being offered. It can vary from 4 to 0 depending on the number of knots and their quality. It is imperative to check the length of the lumber and the cross-sectional dimensions. If bends or rotational deformations are visible, then it is better to refrain from purchasing such products. You can check the evenness of the lumber by applying a stretched cord.

You probably noticed that parquet boards have different patterns when cut: even stripes or random, with a large number of lines and circles.

Radial cutting of wood - elite boards for select parquet

To get that same “striped” pattern, the log is sawn strictly along the radius. But radial cutting produces a lot of waste, so ready-made boards rise in price. In addition, the wood is less porous and therefore more wear-resistant, which also affects the cost. That's why radial cutting is considered elite.

Tangential cutting of wood - ordinary parquet boards

When producing a regular board, the cutting plane runs at a distance from the center tangentially to the growth rings. This way you get more boards from one log, but the pattern will be unpredictable, with a lot of curls, lines, spots and rings. Wood looks more natural. Unlike radial cut boards, in this case the wood is more porous and less resistant to wear. Therefore, tangential cut parquet belongs to the economy class.

Thanks to modern technologies production, as well as special compounds for impregnation of parquet, the durability of tangentially cut wood increases.

For many centuries, humanity has been using wood as a building material and, despite the constant emergence of new ones, modern materials, the popularity of natural wood is not decreasing at all.

How to choose the right lumber from a huge assortment? What causes the differences in price and quality?

The quality of finished wood materials depends on many parameters - the type of wood and the quality of the original timber, the professionalism of machine operators, compliance with the technology of drying lumber and the production of finished products. Another factor that has a significant impact on the quality and appearance lumber, as well as their mechanical properties, is the method of cutting wood that determines the texture of the board.

There are several types of wood cutting - tangential, radial, rustic and transverse, of which the first two are most widespread. To understand the difference between types of cuts, you need to have a good knowledge of the structure of wood and understand the technology of sawing wood.

At cross cut The wood is cut across the grain. The method is used in the production of artistic parquet. A rustic cut is any cut made at an acute angle to the direction of the grain. The method is used in the production of lumber for rustic flooring - the most heterogeneous and original in pattern and shade.

With a tangential cut, the cut plane runs tangentially to the annual layers of the tree at some distance from the core. Since wood fibers, as a rule, do not have a single direction, they create natural patterns on the surface of the board in the form of fancy “arches”, “curls”, “rings”. The texture of the resulting tangential cut board is uneven and may contain wood pores. Some of the dry boards may develop delaminations on the surface after finishing planing. After tangential cutting, boards are characterized by higher coefficients of shrinkage and swelling; moreover, such a scheme for sawing logs allows an increase in the useful yield, which in turn leads to a reduction in the cost of the board.

For radial cutting of wood, the cutting plane is located perpendicular to the annual rings. With this method, the texture of the board is quite uniform with a minimum distance between the annual layers. This not only creates a beautiful pattern, but also increases the strength of the lumber.

Radial cut boards are distinguished by good resistance to external influences, have greater resistance to deformation and wear resistance than tangential cut boards.

The shrinkage and swelling coefficients of radially cut lumber are 0.18% and 0.2%, respectively, which is almost two times better than that of tangentially cut lumber. The reason for this phenomenon is that for radial cut boards, shrinkage and swelling occur along the thickness of the material, in contrast to tangential cut boards, in which dimensional changes occur along the width of the board. This explains the fact that in finished products (parquet boards, floor boards, block houses, imitation timber, lining) made from radially cut lumber, there are almost no gaps on the front surface, which is not excluded in products made from tangentially cut lumber. To obtain laminated veneer lumber by splicing wood without knots, blanks and boards of radial and semi-radial cuts are used, since the mechanical and geometric characteristics of the timber depend on the resistance of the fibers, which increases when gluing layers with multidirectional annual rings with an inclination angle of up to 45°.

The average useful yield of radial cut boards is only 10-15%. This explains their high cost. Radial cutting includes lamellas in which the angle between the annual rings and the blade is 60-90°. If the specified angle is in the range of 45-60°, such boards are classified as semi-radial cut. The best performance properties are found in lumber in which the angle between the annual layers and the cutting plane is 80-90 degrees. Taking into account semi-radial cut boards, the useful yield coefficient can reach 30%.

Typically, when radial sawing, the log is initially sawn into quarters, and then from each quarter, boards are sawn off alternately from two layers. For sawing logs in a radial way, for example, UP-700 longitudinal sawing machines can be used. Of great importance is the UP-700 microprocessor control and optimization system, which is used by technologists to determine the percentage of yield of radial cut boards based on the criteria for optimizing the maximum yield of the finished product, as well as the conditions of radial and semi-radial cutting.

Comparing radial and tangential types of cuts, several conclusions can be drawn:

1. Radial lumber has better shrinkage and swelling properties.
2. Radial cut boards have better mechanical characteristics and dimensional stability.
3. The wood of radial cut boards has a uniform shade and uniform texture, which gives a special decorative value to finished wood products.
4. Due to their characteristics, radial boards are more widely used, although they have a higher price.