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Wood finishes (paint, varnish, and stain, for example) give a desired appearance, protect wood surfaces, and provide a cleanable surface. Many people consider appearance most important when choosing finishes for wood (lumber and wood composites). However, from a technical aspect, protection is most important for wood used outdoors, and providing a cleanable surface is most important for wood used indoors. When selecting a finish, one should consider appearance,
anti slip decking suppliers in northern irelandprotection, and cleanability and also how bulk and surface properties of wood affect finish application and performance (how long a finish lasts��its service life). Wood properties such as density (specific gravity), growth rate, heartwood�Csapwood, earlywood�Clatewood, grain angle, vessels,and texture vary within and across wood species.
Wood composites, such as plywood, fiberboard, and oriented strandboard (OSB), have different properties. Of the 18,000 to 25,000 known wood species (exact number varies depending on the grouping of species), approximately 50 are commercial species used in the United States and Canada. Chapters 2�C4 give their properties. Of these commercial species, researchers report finishing characteristics for only a few species common to North America, Europe, Japan, and the tropics. However, if one understands how wood properties, finish, and environmental conditions interact, it should be possible to estimate finish performance for most wood species.
abrasion resistance plastic wood products thailand Performance depends on choosing an appropriate finish for wood, considering the use conditions, and applying finishes correctly in sufficient amount. For long service life, choose wood products and finishes appropriate for environments where they are used. Indoor use places less stress on finishes than outdoor use. A climate having severe seasonal changes (U.S. Upper Midwest, for example) places greater stress on finishes then does a mild climate (such as the Pacific Northwest). Guidelines in this chapter explain how to obtain long service life for contemporary finishes on lumber and wood composites used in the United States and Canada.
The chapter begins with a review of wood properties important for wood finishing and describes effects of water and weathering on wood and finishes. This background establishes a basis for describing finishes for wood, their application, and common types of finish failures (and ways to avoid them). Publications listed at the end of this chapter provide additional information.Most wood cells (called tracheids in softwoods, fibers in hardwoods) align parallel (axial) to the stem or branch.
composite materials wood plasticSoftwood tracheids support the tree and transport water and nutrients. Hardwood fibers just support the tree; hardwoods have special cells (vessels) for transporting water and nutrients. Vessel cells are open at each end and stacked to form ��pipes.�� Axial tracheids and fibers are hollow tubes closed at each end. In softwoods, liquids move in the axial direction by flowing from one tracheid to another through openings called pits.
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