Build Daily

August 12, 2017 18:06

Types of timber and lumber characteristics

None of today available on the market of building materials does not have such unique qualities as a natural wood.It is very convenient and easy to handle, so that you can do anything, even a spoon, though the aircraft fuselage.Wood has excellent strength, it is light and has a pleasant smell.Working with wood brings a real pleasure, if to understand that what are the types and characteristics of wood lumber.

Construction of wood

Construction of wood

Species cuts wood

If you look at any wood blocks, you can see it on the texture pattern formed annual rings.Its appearance depends on the trunk of the tree was sawn in what direction.Adopted saw him in three directions: up and down fibers, and also at an angle of 45 degrees.If you make the cut at an angle, it is called tangential.It forms a texture similar to the cone-shaped line.

Three different kinds of sections depending on the direction

Three different types of sections depending on the direction

If the cut is made parallel to the grain, it is called a groove.It is clearly visible parallel lines formed by the fibers.A

cross section in all its glory, we presents the annual rings of a tree trunk.Image is important for the outer beauty of wood products, so before making the wood itself should clearly represent the direction in which we want to have patterns.

internal structure of wood

In order to understand the structure of the tree trunk is necessary to make a full cross-sectional view.The top layer is called the cortex.It is of no interest, so it is removed.Next a thin layer - the so-called growth zone.It is difficult to see, but if a young tree, after the removal of the bark can be seen green fibers, wet to the touch.They are called the cambium.After it begins the wood itself with pronounced growth rings.The professionals it is called sapwood.In the center of the trunk is darker or merges with the nucleus of the sapwood.It depends on the type of wood that can be sapwood or heartwood.

Sound tree species are represented by all coniferous (cedar, pine, spruce, larch, yew) and some common deciduous species such as oak, poplar, ash.The vast majority of the trees are deciduous sapwood: birch, alder, hornbeam, maple.

density wood cells influences the strength and other physical properties of wood, but on the creation of artistic compositions and the possibility of using one or another raw material in the impact pattern of annual rings and heart-shaped vessels.It macrostructural elements, and they include more knots, growths, undeveloped sprouts, deflecting annual rings and form a variety of irregular grain.

Wood with clearly marked macrostructure is most interesting for processing because diy used, without exception, all conifers

Physical characteristics of wood

Like any building material wood has a number of physical properties:

  • density is measured in g / cm3, depending on the breedwood and its moisture content.The higher the number, the stronger and harder material, it is more durable and less susceptible to rotting.The most dense considered oak, ash, maple and larch, and the lowest density exhibit aspen, spruce and fir.
  • wood Humidity speaks volumes about its quality and durability.Room-dry is 8 - 12% moisture, dry air from 12 to 18%, and atmospheric-dry 18 - 23%.If more moisture, it is called a raw wood.
  • sound conductivity and thermal conductivity of the important qualities.High-quality dry wood retains heat well, and the sound in the transverse direction.Along the thermal conductivity of the fibers is reduced, but the sound is perfectly distributed along the barrel.It's even an indicator of the quality and dryness.
  • corrosion resistance, which is higher in softwood, thanks to the resin therein.
  • texture, color, smell and shine it possible to determine the breed of timber and determine its decorative value.

All of these physical properties are very important for the use of a particular tree species.

Mechanical properties of wood

mechanical properties of different types of wood are more important.After all, they affect the strength and durability of structures or wood products.Mechanical strength - the ability to resist to various static and dynamic influences from outside.The strength of a material is dependent on the direction of action of the load.In this regard, to distinguish shearing strength or shear, bending and compression.Any wood has great strength along the grain than across them.

Test the strength of a piece of wood on the loading direction

strength test on a piece of wood

load direction should be noted that wet wood becomes less strong.This is seen in the light and loose rock.

Plasticity - this is a property that allows you to create bent parts made of wood.More plastic rocks retain their shape, obtained by a certain long-term exposure.Humidity and temperature greatly increase the rate, so the bent parts for producing wood is exposed to hot water or steam.High plasticity boasts beech, elm, oak, ash.This is not the conifers, because the structure of the fiber is too straightforward.

hardness of wood - the ability to resist the introduction of different foreign bodies into it.There are hardwood, such as beech, maple, larch, oak, ash, elm (the hardest are boxwood and acacia) and soft, such as basswood, alder, fir, pine.wood durability level depends on its hardness.

characteristics of different types of wood

for different purposes use a particular type of wood.All of them are divided into coniferous and deciduous.The former have a sharp smell of resin and expressed macrostructure.The most common conifers are: cedar, pine, fir, spruce and larch.

  • Pine is the most common building material.Its color changes from pale yellow to reddish yellow.The wood is light enough and strong.The main thing is that it is very easy to handle.It contains a lot of resin, so it rots badly and not particularly afraid of rainfall.Because of its softness, it easily takes a variety of dyes and varnishes.Warping during drying almost pine occurs.The disadvantage is the impossibility of quality finishing and painting.However, it is successfully used for the production of furniture and plywood.
  • Spruce can be put on the second place after the pine trees on the level of use.Resins it is not much, so it is more susceptible to rotting and exposed to precipitation.Wood spruce strong and light, but it has a large number of knots, which significantly reduces its consumer qualities.Benefits include the white color of the wood and a small resinous.It is well retains various fasteners.The construction of it do not the most important details.
  • cedar or Siberian pine correctly does not yield ate in their construction quality, and for resistance to decay is much superior to her.Despite the softness of cedar wood, it has a good density and strength, while perfectly treatable.
  • Fir is no different from eating: it is easy to any treatment and does not accept corrosive chemicals.It is sufficiently small pitch, for which the wood rots too quickly without special treatment.
  • Larch appreciated its hardness and strength.Its density is such that the trunk of the tree sinks in water.But larch practically does not rot.

Hardwood can be divided into hard and soft.Their timber has no odor.He is the only fresh saw cut.It is necessary to carry hardwood oak, ash and birch and softwood to alder and aspen.

  • Oak has a very high strength and resistance to the appearance of decay.Its wood has a beautiful color and texture.It will not crack or warp, so make Oak furniture and luxury goods and art.Tannins have strong antiseptic properties.The most durable and beautiful oak wood is obtained when it held 1.5 years in cold running water.Its color is black.From a stained wood furniture made of expensive items.It is an ideal material for the production of furniture, but it is very inconvenient to process because of its density and strength
  • Birch wood has a high density and hardness.It is sturdy and quite viscous, it is not very pronounced texture, but homogeneous.The disadvantages of this material are subject to heavy cracking and warping, shrinkage is too strong, a small resistance to decay, rather frequent defeat this illness, like a wormhole.However, it is a good idea to process with hand tools, glues in plywood, easily polished and subjected to coloring, gives the ability to produce very fine relief carving.
  • Aspen has a fairly soft wood, which is so small knots, it lends itself well to any treatment.However, its porous structure does not allow for fine details.
  • Linden is highly valued in the manufacture of various carved pieces of furniture production.It does not warp and does not crack during shrinkage.Linden wood has a strong enough structure that lends itself to very little decay.
  • Maple has a strong, dense wood and slabousyhayuschey.It almost does not warp, rot but quickly and strongly subject to a wormhole.This wood is treated bad, glued, painted and finished with.It is used in the carvings, and the manufacture of parts of the array.
  • Red tree that grows in evergreen tropical forests, timber is red.This is something no one type, and the set with similar properties.Wood mahogany wood is very soft and easy to work perfectly, easy to polish and varnish absorbs.Some pieces of furniture made from such timber.Its high cost does not allow to do all of it is completely the product.

Rare wood

Rare wood

Rare wood

Lumber and varieties

Mostly on lesobaze and shop selling dry wood.Crude sold rare.If you decide to build something or to make a piece of furniture, then you come up with the names of species of timber, the meaning of which is understood:

  • Boules is essentially one piece tree trunks without bark or pieces of sufficient length.It is important that their diameter is greater than 25 cm
  • Podvyaznikov -. The same ridge, but a diameter of less than 25 cm
  • poles -. One-piece trunk bark diameter of less than 9 cm
  • Plate -. It is half the ridge, which is sawn along the grain.
  • quarters - half of the plate, sawn along the grain.
  • Lejeune, or in another timber to wane - is trimmed on both sides of the beam, which can be put on one of the two planes.
  • Bruce call log, which trimmed on all four sides with a cross section of not less than 100x100 mm.If it is less, then the product is called the bar.
  • board can be very different depending on the method of processing and sizes: unedged, edged, croaker, planed on all four sides, decking, fanfold.
Cross sections of boards depending on the treatment .

Transverse sections of boards, depending on the treatment.

All lumber, which are usually used in construction, have their own specific names.They differ in the thickness of the product, and this ratio of width to thickness.For boards, this ratio must never be greater than 2. The maximum permissible thickness of the boards is 100 mm.The length of any material from the hardwood does not exceed 5 m and 6.5 m from coniferous.

The main types of lumber

The main types of lumber

reading this article, you are familiar with the basic concepts and characteristics of the wood.So with this knowledge, you can easily purchase timber, operating terms, as good sellers.Today, virtually no major construction or renovation can not do without the use of wood in varying degrees, so that knowledge will be very useful.