Report, Tema 21U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, 1945 |
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Términos y frases comunes
acre air seasoning air-dried stock amount annual average board-foot volume boxes and crates brush areas cants central supply yard central yard charcoal and fuel conifers consumer consumption cords cost crooked logs Cuba dimension stock domestic Dominican Republic dry kiln economical END RACK equipment estimate expanded export factory Federal Forest finished forest areas forest drain forest land forest resources fuel wood grades growth Haiti handle hardwoods imported lumber inches industry island kiln dried kiln trucks less locally produced logs longleaf pine lumber production mahogany and cedro methods of operation mill million board feet millwork minimum moisture content normal demand obtained percent pile pine planks plant practice present probably produced locally Puerto Rico Development requirements resaw Rico Development Company Rip saw San Juan sawlog sawmill sawn SHADA shed shipment space species squares standard stickers tabonuco termite thousand board feet Trujillo United Whipsawed Wood fuel wood products
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Página 44 - When possible it is good practice to season the stock in the board or plank form before working up into dimension stock. The handling costs are also materially greater than for an equal footage of material in board form. The requirements of the various consumers may mean a considerable number of standard sizes would be required. Production efficiency and quick handling of stock may mean that the number of sizes produced be kept at a minimum, making only those standard items in greatest demand.
Página 32 - These improvements in the quality of the stock occur where certain piling practices, that have been found to give the best results, are followed. Some mill operators in Chile have adopted the same practices in whole or in part, and consider them a distinct improvement over the customary piling method. Piling that is correct for air -seasoning must be of a type that provides suitable...
Página 43 - ... which means that a large number of pieces of identical size and shape are required. In producing these pieces from boards a certain amount of waste in making the cuttings is inevitable, the yield in clear cuttings often being only 50 to 60 percent of the original footage in the upper grades of lumber and less in. the lower grades.
Página 44 - There are, of course, certain problems in producing dimension stock that must be considered and overcome for successful operation. Seasoning, for example, has been one of the big stumbling blocks in dimension stock production. When dimension stock is cut from green material, it is more likely to warp and twist during subsequent seasoning than when seasoned in the board fora.
Página 32 - On the other hand, hardwoods are in general much more difficult to season than most of the conifers and require a much longer period in the kiln. This means that several times as much kiln space is required to dry a given amount of hardwood compared to an equal volume of conifers. Moreover, most hardwood forests contain mixed species that require separation since they cannot "be economically dried together under the same drying schedule.
Página 43 - The same problem of cutting applies to the manufacture of most furniture items, such as tables, beds, dressers, etc., and also to planing mill products, such as doors, windows, parquetry flooring, and some items of interior trim. It applies to the box and container industry in producing box shooks and to most of the other woodworking industries to some degree. If these standard sized cuttings were produced at the central supply yard, a number of definite advantages accrue.
Página 34 - The space provided below the pile allows this cool moist air to escape readily. (2) The pile is given a slope, front to rear, so as to permit easy and positive drainage of any rain or snow water that may gain entrance to the pile. (3) The stickers are placed close enough together so as to furnish adequate support against warping between supports. The amount of surface...
Página 43 - In making cuttings for tables and beds where relatively long lengths are required, there are numerous pieces that are left as waste that would produce short or narrow cuttings suitable for use in other products.