Plywood can handle a variety of ways, as a standard manual or electric woodworking tools. However, it should be noted that the glue in the plywood causing rapid wear of cutting tools, it is recommended to use the tools of hard alloys. Veneers can also be cut with modern cutting systems, laser beams and hydraulic pressure of 3500 bar. Sawing sawing best result is obtained by using tape or a circular saw. To get a clean cut, cutting should be done correctly. First, cutting is performed across the grain of the front side, then go along. This method avoids the splitting angles. At best, the front side of the plywood is hand-sawn or band saw, on the other side - the disk or contour. When sawing a circular saw blade is recommended high speed and low delivery rate. Limit the penetration of teeth saw blade to be small. Drilling holes with smooth edges are obtained if the drill bit rather sharp and is equipped with front cutter. Drilling should begin with the front side. Splittings on the back plate can be avoided by use underlayment sheet. The use of nails for panels to the walls, ceiling and floor are best suited nails with thread or special screws, preferably hat has been hidden or dented. For a secret nailing fit the usual wire nails. Acid nails are recommended for nailing nails exterior cladding panels, because they give better protection against rust on the surface of the panel. The length of the nails should be the thickness of 2.5-3 bar. Considered suitable interval between the nails for panels to the walls and ceiling - 10-20 cm along the edges, 20-30 cm - in the middle, depending on the load and the type of nails. In the panels under the floor of the interval should be 20-30 cm along the edges and 40-50 cm in the middle. Due to the fact that the structure of a plywood board represents the strip of veneer with a transverse fibers, the nails can score close to the edge. Considered suitable distance from the panel edge at 12-15 mm. In structures that are resistant to stress the important role played to their strength and integrity of fixation nails. Nails need to nail down in the correct order, they should be long with big heads. You can use screws. As noted above, the fixation structures may also be improved through the use of glue at the joints. Screw connections in many areas of the plywood panels are fastened with screws. In finishing, the manufacture of furniture, exhibition stands and shipbuilding, the preference is screws. Auxiliary holes may be pre-drilled, with the hole in the panel must match the diameter of the screw and the smaller openings in the frame, the diameter of the latter will be half of its predecessor. Vkruchennogo screw cap should not penetrate the face veneer. If you use nails with a domed cap, you must use the washer. When fastening the plywood sheathing to metal components designs can use special screws to secure the plywood panels on the back side without damaging the front side. Panel under the floor of cargo containers and trailers are normally attached to the metal chassis using Self-tapping screw thread. For example, the plywood boards 27 mm thick can be fastened with screws M6h40 mm. Screw first penetrates the plywood and then cut through the threads in the metal. This method is fast enough. Thin plywood panels for transport engineering as easily attached to the metal structure by means of the above Self-tapping screws. Plywood boards is easily fixed by bolts. Bolt hole should be 2 mm larger than the diameter of the bolt. Under the caps bolts must be nuts and washers to protect the panel surface. To avoid damaging the wood under the bolt does not tighten the bolt too much. Where plywood is used outdoors, too much tightened bolt can press into the surface of the plate, and it will swell from moisture. This will lead to the formation of cracks in the surface of the plywood around the bolt. Locks, hinges, shelves, etc. can be easily and securely attached to the surface of the plywood on either side or edge. The most durable is fixed with jigs. If you want to put the screws on the edges of the panels, the holes for them should be pre-drilled. Installation of Plywood can be attached to the design with glue, nails, staples, screws, rivets or bolts. When deciding how to mount, it is important to take into account the operating conditions, required strength and appearance. Before mounting the plywood should be prepared in terms of the final operating conditions should be taken precautions to prevent the possible expansion or compression plate from exposure to moisture or temperature changes. Deemed necessary clearance in the joints of 2 mm. You can use an elastic filler, for example, between the edge of the panel and steel frame construction. In designs with heating is necessary to ensure adequate ventilation of the plywood boards. Types of connections joints and connections are important components of plywood structures. There are many types of connections plywood: groove and tongue, spikes, and others. If done correctly, they provide a reliable design of walls, floor and supporting elements. The ends of plywood sheets - this is usually the most sensitive part, so special attention should be given to treatment of joints, especially if the plywood is intended for use outdoors. The walls and ceilings are recommended splice, open, groove-ridge, seam and joint bars. In the outdoor, various compounds stripes provide the best protection against external influences. Vertical and horizontal profiles made of aluminum, effectively protects the edge of the plywood boards. Resistance to rust, making them suitable material for facades. However, if for architectural reasons to use outdoors preference is an open connection, the edges must be properly processed. About 2 mm / m should be kept under the extension of the panel. In the butt, this distance should be 3-6 mm. Groove-ridge compound commonly used for flooring and panels that go under the roof. It effectively prevents the lifting of panels and damage to roofing materials, can withstand heavy loads than conventional butt. The panel is attached with a secret prikolachivaniya nails. The best load-carrying capacity is achieved by applying a stepped profile or similar special section with flanges that support the edge of adjacent panels. These profiles are used, for example, in the construction of floors for cargo containers or trailers. Bonding Exposed plywood is usually glued to any wood glue. The choice of adhesive depends on the method of operation, the moisture content in the final use and the strength required. Conventional types of glue: PVA, phenol, epoxy, polyurethane, etc. PVA glue suitable for indoor use. This adhesive is colorless and has a good strength adhesive. Phenol and epoxy adhesives have high strength adhesive that can withstand adverse environmental conditions. When gluing the plywood with metal epoxy adhesive is recommended type. Contact adhesives are typically used for bonding large surfaces and veneered plywood, designed for indoor use. Not recommended glue laminated plywood. Plywood, film-coating is not capable of long-term bonding. If the plywood is attached to the coated adhesive stuck to the surface must first clean up to the layer of wood, for example, using sandpaper. It is desirable that the adhesive was epoxy. Bonded surface must be clean and dry. Glue should be applied uniformly to both bonding surfaces by roller or brush. The desired pressure force is achieved by means of clips, screws or nails. Appropriate spacing between the nails - 1 nail a 40 cm2. Any excess glue should be removed prior to freezing. You should always carefully read the manufacturer's instructions glue. Grinding surface of plywood is usually sanded relatively coarse sandpaper (№ 80 - 100) perpendicular to the texture of wood. If you want exceptionally smooth handling, for example, for high quality coating, it is recommended fine sanding paper in the longitudinal direction of wood grain. Surface finish of polished, smooth surface of plywood is an excellent basis for further finishing. Can be laminated plywood, laminated, dyed, impregnated with a special paint or mortar, etc. When selecting paint or soil solution, it is important to take into account the tendency to form cracks in the veneer veneer. The surface may also be covered with laminate or veneer of valuable timber. Possible to use a thin film. Veneers can also be papered with wallpaper. If the plywood boards was stored in high humidity conditions, before finishing them must be dried to a normal moisture content. The surface should be thoroughly cleaned from dust, which appeared as a result of previous treatment. This procedure must be repeated before each stage finish. Depending on the desired quality, 1 -2 applied coating layer. Treatment of the edges to align the edges of the plates after cutting, they can be a little trim. The best result is achieved if the chip in a direction from the corners toward the middle, thus avoiding splitting at the corners. Edge of the panel can also be sanded. Colouring edges is 2-3 times with acrylic paint with special additives. Primer Wood refers to natural materials, which expands and contracts depending on the combined effect of temperature and humidity of the environment (despite the transverse layers of veneer within the plate). On the inner side of the face veneer observed cracks, which expand and contract under the influence of humidity fluctuations. Because of these reasons requires pre-primer for subsequent painting. Used elastic paint, and it is important the right combination of colors. Painting the base paper is completely prevents the formation of cracks in the layer of paint due to moisture in high humidity and outdoor use plywood panels must be painted and the back side. In such circumstances, Edges is important and should be done carefully and repeatedly. Plywood, designed for outdoor use, should be painted with special paints. Painting Drawing paint gives a natural texture veneer pattern. The surface of the plate can also be painted in full, without the hassles of wood texture. Apply by brush or spray. Color plywood is acceptable for both internal and external decoration. But before final painting the surface should be treated with a special solution to prevent the appearance of blue and fungi as biological stability of transparent colors is limited because of the minimum content of binder. Lacquered birch plywood with lacquered surface is pleasant to look at and easy to keep clean. Before varnishing the panel surface to be polished fine-grain sandpaper. Dust, formed during grinding must be carefully removed and the surface is covered with diluted varnish.
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