Wood warping

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Different types of wood warping Wood warping.png
Different types of wood warping

Wood warping is a deviation from flatness in timber as a result of internal residual stress caused by uneven shrinkage. Warping primarily occurs due to uneven expansion or contraction caused by changes in moisture content. Warping can occur in wood considered "dry" (wood can take up and release moisture indefinitely [1] ) when it takes up moisture unevenly, or when it is allowed to return to its "dry" equilibrium state unevenly, too slowly, or too quickly. Many factors can contribute to wood warp susceptibility: wood species, grain orientation, air flow, sunlight, uneven finishing, temperature, and cutting season.

Contents

The types of wood warping include:

Wood warping costs the wood industry in the U.S. millions of dollars per year.[ citation needed ] Straight wood boards that leave a cutting facility sometimes arrive at the store yard warped. Although wood warping has been studied for years, the warping control model for manufacturing composite wood hasn't been updated for about 40 years.[ citation needed ]

Zhiyong Cai, researcher at Texas A&M University, has researched wood warping and was working on a computer software program in 2003 to help manufacturers make changes in the manufacturing process so that wood doesn't arrive at its destination warped after it leaves the mill or factory. [2] [3]

See also

Related Research Articles

<span class="mw-page-title-main">Wood</span> Fibrous material from trees or other plants

Wood is a structural tissue found in the stems and roots of trees and other woody plants. It is an organic material – a natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include the same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree it performs a support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients between the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips, or fiber.

<span class="mw-page-title-main">Lumber</span> Wood that has been processed into beams and planks

Lumber is wood that has been processed into uniform and useful sizes, including beams and planks or boards. Lumber is mainly used for construction framing, as well as finishing. Lumber has many uses beyond home building. Lumber is referred to as timber in the United Kingdom, Europe, Australia, and New Zealand, while in other parts of the world the term timber refers specifically to unprocessed wood fiber, such as cut logs or standing trees that have yet to be cut.

<span class="mw-page-title-main">Plywood</span> Manufactured wood panel made from thin sheets of wood veneer

Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that have been stacked and glued together. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboard (MDF), oriented strand board (OSB), and particle board.

<span class="mw-page-title-main">Corrugated fiberboard</span> Composite paper material

Corrugated fiberboard, corrugated cardboard, or corrugated is a type of packaging material consisting of a fluted corrugated sheet and one or two flat linerboards. It is made on "flute lamination machines" or "corrugators" and is used for making corrugated boxes. The corrugated medium sheet and the linerboard(s) are made of kraft containerboard, a paperboard material usually over 0.25 millimetres (0.01 in) thick.

<span class="mw-page-title-main">Pulp (paper)</span> Fibrous material used notably in papermaking

Pulp is a fibrous lignocellulosic material prepared by chemically, semi-chemically or mechanically producing cellulosic fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemicals or plant-based additives, pulp is the major raw material used in papermaking and the industrial production of other paper products.

<span class="mw-page-title-main">Medium-density fibreboard</span> Engineered wood product

Medium-density fibreboard (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibre, often in a defibrator, combining it with wax and a resin binder, and forming it into panels by applying high temperature and pressure. MDF is generally denser than plywood. It is made up of separated fibre but can be used as a building material similar in application to plywood. It is stronger and denser than particle board.

<span class="mw-page-title-main">Firewood</span> Wood used for fires

Firewood is any wooden material that is gathered and used for fuel. Generally, firewood is not heavily processed and is in some sort of recognizable log or branch form, compared to other forms of wood fuel like pellets. Firewood can be seasoned and heat treated (dry) or unseasoned (fresh/wet). It is generally classified as either hardwood or softwood.

<span class="mw-page-title-main">Pulpwood</span> Timber intended for processing into wood pulp for paper production

Pulpwood can be defined as timber that is ground and processed into a fibrous pulp. It is a versatile natural resource commonly used for paper-making but also made into low-grade wood and used for chips, energy, pellets, and engineered products.

<span class="mw-page-title-main">Woodworm</span> Wood-eating beetle larva

A woodworm is the wood-eating larva of many species of beetle. It is also a generic description given to the infestation of a wooden item by these larvae.

<span class="mw-page-title-main">Woodturning</span> Craft

Woodturning is the craft of using a wood lathe with hand-held tools to cut a shape that is symmetrical around the axis of rotation. Like the potter's wheel, the wood lathe is a mechanism that can generate a variety of forms. The operator is known as a turner, and the skills needed to use the tools were traditionally known as turnery. In pre-industrial England, these skills were sufficiently difficult to be known as "the mysteries of the turners' guild." The skills to use the tools by hand, without a fixed point of contact with the wood, distinguish woodturning and the wood lathe from the machinist's lathe, or metal-working lathe.

<span class="mw-page-title-main">Log house</span> House built from wooden logs

A log house, or log building, is a structure built with horizontal logs interlocked at the corners by notching. Logs may be round, squared or hewn to other shapes, either handcrafted or milled. The term "log cabin" generally refers to a smaller, more rustic log house, such as a hunting cabin in the woods, that may or may not have electricity or plumbing.

<span class="mw-page-title-main">Dry rot</span> Fungal wood decay

Dry rot is wood decay caused by one of several species of fungi that digest parts of wood which give it strength and stiffness. It was previously used to describe any decay of cured wood in ships and buildings by a fungus which resulted in a darkly colored deteriorated and cracked condition.

<span class="mw-page-title-main">Ard (plough)</span> Simple light plough without a mouldboard

The ard, ard plough, or scratch plough is a simple light plough without a mouldboard. It is symmetrical on either side of its line of draft and is fitted with a symmetrical share that traces a shallow furrow but does not invert the soil. It began to be replaced in China by the heavy carruca turnplough in the 1st century, and in most of Europe from the 7th century.

<span class="mw-page-title-main">Wood drying</span> Also known as seasoning, which is the reduction of the moisture content of wood prior to its use

Wood drying reduces the moisture content of wood before its use. When the drying is done in a kiln, the product is known as kiln-dried timber or lumber, whereas air drying is the more traditional method.

<span class="mw-page-title-main">Quarter sawing</span> Woodworking process

Quarter sawing or quartersawing is a woodworking process that produces quarter-sawn or quarter-cut boards in the rip cutting of logs into lumber. The resulting lumber can also be called radially-sawn or simply quartered. There is widespread confusion between the terms rift sawn and quarter sawn with the terms defined both with opposite meanings and as synonyms.

This glossary of woodworking lists a number of specialized terms and concepts used in woodworking, carpentry, and related disciplines.

<span class="mw-page-title-main">Wood flooring</span> Product manufactured from timber that is designed for use as flooring

Wood flooring is any product manufactured from timber that is designed for use as flooring, either structural or aesthetic. Wood is a common choice as a flooring material and can come in various styles, colors, cuts, and species. Bamboo flooring is often considered a form of wood flooring, although it is made from bamboo rather than timber.

<span class="mw-page-title-main">Parallel-strand lumber</span> Form of engineered wood

Parallel-strand lumber (PSL) is a form of engineered wood made from parallel wood strands bonded together with adhesive. It is used for beams, headers, columns, and posts, among other uses. The strands in PSL are clipped veneer elements having a least dimension of not more than 14 inch (6.4 mm) and an average length of at least 300 times this least dimension. It is a member of the structural composite lumber (SCL) family of engineered wood products.

<span class="mw-page-title-main">Wood-burning stove</span> Type of stove

A wood-burning stove is a heating or cooking appliance capable of burning wood fuel, often called solid fuel, and wood-derived biomass fuel, such as sawdust bricks. Generally the appliance consists of a solid metal closed firebox, often lined by fire brick, and one or more air controls. The first wood-burning stove was patented in Strasbourg in 1557. This was two centuries before the Industrial Revolution, so iron was still prohibitively expensive. The first wood-burning stoves were high-end consumer items and only gradually became used widely.

<span class="mw-page-title-main">Moisture meter</span> Instrument used to measure moisture content

Moisture meters are measuring instruments used to measure the percentage of water in a given substance, as physical properties are strongly affected by moisture content and high moisture content for a period of time may progressively degrade a material. Meters exist for various substances, including wood, building materials, concrete, and soil.

References

  1. Loffer, Larry (2020-09-30). "Acceptable Moisture Levels in Wood - Knowing the Moisture Content". Wagner Meters. Retrieved 2024-03-09.
  2. "WARPED IDEA: WAYS TO STOP SWAYED WOOD MAY BE AROUND THE BEND". today.agrilife.org. 15 April 2003. Retrieved 2018-09-12.
  3. Cai, Zhiyong, Dickens, James R (2004). "Wood composite warping: Modeling and simulation". Wood and Fiber Science. 36 (2). Soc Wood Sc Tech: 174–185.{{cite journal}}: CS1 maint: multiple names: authors list (link)

Further reading