Choosing a band sawmill

There are many manufacturers and many design features band sawmill. In order not to bore the reader, we briefly discuss the major key aspects of the choice of quality sawmills. 1. The design of the portal machine: the machine portal is to be made of square-shaped tube with the largest possible number of reinforcing elements. This allows for maximum rigidity and minimal vibration as a consequence of the saw assembly during the cutting of thick wood. Some manufacturers are especially popular brand can afford to save on metal and simplifies the construction of the portal machine by reducing the reinforcing elements, which undoubtedly affects the quality of the cutting material (this corrugation, wave) and in the life machine. He just falls apart, covered with microcracks in welds. 2. Rolling pin guides vertical movement of the saw unit: Must be made of solid metal, be sure to ground its entire length. This is the main criterion for this machine on the rules of engineering. If you are told that the guides are made of square-shaped tubes, even polished a machine not worth buying. Why? The average thickness of the walls shaped tubes of 3mm. In the process of polishing removed a certain layer of metal, as a consequence of reduced wall thickness of the guide tube to 2 mm! This is unacceptable, because in the process of cutting the main burden falls on rails, and then to the portal machine. For several months there bedsores, and for the year there are holes in the ground movement of the saw unit in the guide, made of hollow core or round tubes. Some manufacturers cover the rails with rubber ribbed, ostensibly to protect against dust, dirt, sawdust in the process of cutting, but often in fact, they usually hide the water pipes are often unpolished. Beware!, Round pipe can be abraded from the top, mimicking the one-piece metal, because the inside look and check it is not possible. How to identify? Need to knock on a metal object on the rail, if the sound turns out to be deaf, it means that the hollow tube packed with sand. If the sound will be ringing - it's all metal rail. 3. Mechanism for vertical movement of the saw unit: There should be a screw with two rotors, coupled with the slow-speed engine of growth. Screw-nuts should be made of bronze, not iron, which has a brittle and not suitable for these purposes. The screws should be closed with protective rubber ribbed. Recently, some manufacturers use a band saw machines as a mechanism for vertical movement of the saw unit (instead of screws) Automobile chain, referring to the ease and reliability of the structure. This is not true because in the process of chain stretch, which carries a skewing and jamming the saw unit. It is also not suitable for this purpose rope, which entangled in the mechanism of recovery. Gearmotor, which sets in motion a chain or rope eventually wears out, it appears under the weight of spontaneous rotation and gradual lowering of the cutting unit, particularly from vibrations during cutting, the result - a board at the exit is thicker than at the entrance. Supporters of the chain or rope lifting the saw assembly being persuaded that a weak point screw lift is a bronze nut, which over time can also wear. But in the process of choosing between the replacement of obsolete gear motor or a substitute for bronze nuts economically more expedient to replace the nut, rather than expensive, in most of the imported motor-reducer, which is more expensive than 10 times. 4. Pulleys, which moves the saw tape: There should be no less than 500mm diameter, all-metal, barrel-shaped without spokes as the spokes of cast-iron pulleys in the process occur cracks that lead to its destruction. To facilitate weight pulley allowed a round hole, located on the perimeter of 4 to 6 pieces up to 100 mm. Rubber (futurirovannye) pulleys shall have the following disadvantages, which reduce to zero all the advantages associated with soft rubber speed saw blade: buildup of sawdust on rubber-coated surface, and as a consequence of the appearance of cones from a mixture of sawdust with resin; Failure to use scrapers that clean the saw pulleys, so as with the sawdust cleared rubber layer; impossibility of cutting fluids based on diesel and kerosene, as they corrode the rubber coating. Have the summer to apply water with detergent, which adds moisture timber, and in winter, use antifreeze or non-freezing liquid for washing the windshield of cars, which, of course, expensive; Finally, even under ideal conditions of the rubber coating is sufficient only for a few months, and then should be replaced. Usually, this automobile seat belts, which pull on the saw pulley with montirovok, and belt should be flat with no bumps and hollows, and this is one good belt for 20 low-quality domestic production. 5. Rollers, guides and adhere to the guide tape in the process of sawing: Must have a maximum of adjustments, both in vertical and horizontal planes, as well as rotated by 30 to meet the movement saw the tape. That allows, as if to throw in the process of movement saw blade with a pulley. This reduces the contact of the rear part of the tape guide roller collar in the process of cutting, and as a consequence reduces the number of microcracks grow in the body of the saw, which lead to its destruction. This certainly extends the service life of saw blade. 6. Pulley main engine: There must be a minimum diameter of 140 mm, number of drive belts at least two. On smaller diameter pulleys belts stalled and stretched due to overheating in the maximum diameter of the logs at times, reducing the efficiency and speed of the belt in the process of cutting. The result of cutting the rate falls, there is a feeling that the saw dull. It does not saws, and "nibbles" timber. As a rule, saw in such machines are 2-3 times smaller because of the occurrence of microcracks in the back of the saw blade than on well-designed machines. The optimum belt speed shall be not less than 30 meters per second, less speed saw blade manufacturers do not recommend. Therefore, carefully study the technical details of the machine before you buy. In this paper, we used follow the work of more than two dozen band sawing machines from different manufacturers during the warranty period. 7. Location bandsaw with respect to the log. Consider the main types of location bandsaw with respect to the sawing material: Band saw is perpendicular to the sawed a log, is the most common and well-proven method of cutting. Bandsaw is located at an angle, right shoulder forward. Such an arrangement does not improve the work of sawmills, as increasing the load on the saw, it is more heated and less used, and besides, the machine harder to serve. These tools were created as a new promising development, but in practice did not show good results.