Coniferous trees generally have a soft wood, so the facial details in the articles are rarely used. This is due to the fact that the soft wood is sensitive to mechanical damage and shocks. Practice shows that when the requirements to the process coniferous species can be successfully used for the manufacture of furniture. Products of small size are produced mainly from softwood without knots, with beautiful, pronounced growth rings (cypress, juniper, larch, red pine, etc.). Spruce with lots of knots, as well as white pine and fir - the breed that need more toning decorative or ornamental carvings. Softwood easily stained, but intense color hue suppresses its ornamental value. After drying, the wood shrinks in volume and subjected to the natural warping. In joinery needed to correctly determine the drying of wood, so as nedosushenny and over-dried material is equally unfit for the job. In conditions of normal humidity environment overdried wood inevitably will absorb moisture from the air and winced. At normal wood adversely affects the variable change in temperature: the material in this crack. The state of the wood, its drying and swelling affects a number of reasons: time, harvesting, duration, conditions of exposure, etc. A tree, harvested in winter, wood (compared with summer harvesting) are less wet, as during this period, it slows its growth . It must be remembered that nedosushivanie and overdrying strongest impact on solid and tight and less - the soft and loose. For items to be collected wood homogeneous structure of rocks, to the degree of shrinkage of billets was the same. In sawing the material dries observed deflections and convexity that is going to warping. In central board warpage will be barely noticeable, as the firm heartwood shrinks considerably less than the sapwood. Suitability joinery material to some extent be determined by the external signs svalennogo trunk of the tree. When selecting wood draw attention to the radial crack in the edge: the absence or presence of small cracks indicates the purity of the material, deep cracks are a sign of poor quality. With deep radial cracks in the trunk can be a cavity, which, for example, a pine tree, filled with resinous substance - turpentine (pine, this defect is called pitching). If the cracks are on a one-year segments of wood, ie, by the arcs, then the tree is not suitable for joinery. When you select a soft wood conifers pay attention to the density of growth rings. Than they are thick and their transition smoother, the wood is denser and more homogeneous, and therefore better. Coarse-grained wood points to its friability and the slight strength, products of such timber shall not be subjected to harsh and variable loads. Parallelism of growth rings indicates the relative straightness of wood in longitudinal section, and consequently, the purity of the material. In a separate growing trees after felling and sawing can be observed non-parallelism of wood fibers, ie kososloynost. Together with kososloynostyu of such trees to offset part of the sound sapwood. Wood from these evils more cracks and more warped. When selecting wood should pay attention to the age of the tree. Young wood is soft and friable, and the old are more susceptible to decay, so it is best to choose timber medium, the mature period of growth. So, for joinery is the best pine wood at age 80 ... 90 years oak - 80 ... 150, birch and ash - 60 ... 70, ate - 120, Alder - 60 years, etc. Age svalennogo tree is determined by its transverse transect, which are clearly visible annual layers. In joinery some tree species considered to be more, others - less flexible (elastic). At the same time of the autumn wood harvesting is more flexible than the winter. Established that the greatest flexibility of the tree is shown in his middle age. Flexible breed easily bend, but it is difficult to break. You should know that the flexibility gives linden pine and alder - birch. Linden, birch, elm, aspen are the most flexible, followed by oak, beech, elm, ash, maple, the least flexible are larch, alder, hornbeam, fir, pine. The flexibility of the tree depends on its place of growth, the availability of various nutrients in the soil elementovokruzheniya in which the tree grows (in the middle of the forest or open space), the presence of knots, etc. The joinery for bending wood is very important is its property as viscosity. At high viscosity tree bends in all directions without breaking, but without taking the former straightness. Such as having a maple, elm, juniper, hazel, birch, ash, larch, beech, oak, and the young, etc.; brittle rocks are alder, aspen, spruce, etc. To a large extent on the viscosity and fragility of the wood affects the soil on which the tree grows. Thus, if the pine and beech growing on damp soil, their wood will have a high viscosity, and if dry - then the average. Oak has a high brittleness, if it grows in wet or too dry conditions. In production conditions to obtain a homogeneous viscosity certain breed, before processing pre-steamed, saturating the wood moisture, and then subjected to bending. Wood tends to crack in the direction of the fibers and the more straightforward, its structure, the easier it breaks. Dense and flexible soft-rock split easier. Knotty, curly gain, naplyvnost and entanglement of wood fibers reduce the degree raskalyvaemosti. It is easier to split an oak, beech, ash, alder, spruce, etc., are more difficult - pear, poplar, hornbeam, etc. For a thread picked up rocks with a lower degree raskalyvaemosti. Long storage timber reduces its strength, so the carpenter must comply with conditions of storage of material and finished products to protect against atmospheric influences, covering them with varnish, mastic, etc. In selecting material for joinery, joiners pay attention to color in a cut or flake wood . If its color is uneven or too bright, it indicates which began fungal diseases. Such a tree is not suitable for carpentry work. Knots in detail designs are undesirable because it reduces the strength of wood. Drying of wood, they usually fall. In softwood cavity fallen bitch filled resinous substance, and then there is a "tobacco" twig. Material to the large number of knots used for irresponsible designs.
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