BLOG LINKS for WOOD and WOOD FINISHING

Post 582 by Gautam Shah

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These are few links on Wood and Wood Finishing processes and materials. Categories covered are:

● WOOD-TIMBER

● WOOD FINISHING

● WOOD COATINGS

● PAINTS-THINNERS

● COMPOSITES

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Sawn Timber > Wikipedia image by Kotivalo

 WOOD-TIMBER

WOOD RESOURCES Blog Post 217 Dt 14 Oct 2014

SOFTWOODS and HARDWOODS Blog Post 513 Dt 8 Sept 2015

WOOD COMPOSITES Blog Post 378 Dt 28 March 2015

ROSEWOOD Blog Post 376 Dt 26 March 2015

SOME VARIETIES of WOODS of Indian subcontinent Post 126 Dt 12 July 2015

WOOD-BASED PRODUCTS Blog Post 177 Dt 7 Sept 2014

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Finishing a kokeshi in Japan >Wikipedia image by Fg2

WOOD FINISHING

WOOD SURFACE FINISHING Blog Post 472 Dt 13 July 2015

WOOD FINISHES Blog Post 306 Dt 15 Jan 2015

WOOD FINISHES- Dt 22 July 2014

NATURAL OBJECTS and SELF FINISHES Dt 1 Aug 2014

SURFACE FINISHING PROCESSES Blog Post 504 Dt 24 Aug 2015

SURFACE LEVELLING Blog Post 291 Dt 31 Dec 2014

WHAT ONE CAN DO TO A MATERIAL ? Blog Post 334 Dt 12 Jan 2015

JOINTS in SURFACE FINISHES Blog Post 469 Dt 9 July 2015

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Japanese Lacquer ware in the Ostasiatiska museet, Stockholm, Sweden >Wikipedia image by Daderot

WOOD COATINGS

WOOD SURFACE PREPARATIONS for CLEAR COATINGS Dt 28 April 2014

CLEAR COATINGS Blog Post 182 Dt 12 Sept 2014

CLEAR COATINGS- Post 119 Dt 4 March 2015

SHELLAC or LAC COATINGS Dt 26 April 2014

UNDERSTANDING LACQUERS Blog Post 498 Dt 16 Aug 2015

LACQUERS or NC LACQUERS Blog Post Dt 27 April 2014

VARNISH Dt 25 April 2014

COATINGS as thin Surfacing Blog Post 482 Dt 25 July 2015

CLEAR versus PIGMENTED COATINGS Blog Post 553 Dt 29 Nov 2015

PRIMER COATINGS Blog Post 442 Dt 7 June 2015

APPLICATION of COATINGS Blog Post 300 Dt 9 Jan 2015

COATINGS -surface finishing technologies Blog Post 238 Dt 8 Nov 2014

FILM FORMING PROCESS in COATINGS Blog Post 173 Dt 3 Sept 2014

SINGLE or MULTI-COAT SYSTEMS Blog Post 437 Dt 30 May 2015

METAL COATINGS Blog Post 438 Dt 1 June 2015

GILDING Blog Post 471 Dt 13 July 2015

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Exterior Maple Wood deck staining Flickr image by Olger Fallas

PAINTS-THINNERS

SOLVENTS and THINNERS for coatings Blog Post 320 Dt 29 Jan 2015

PAINT THINNERS – 1 Blog Post 416 Dt 8 May 2015

PAINT THINNERS – Part 2 Blog Post 423 Dt 30 March 2015

SOLVENTS for THINNERS Blog Post 492 Dt 9 Aug 2015

OSB-Platte

Wood chips composite board > Wikipedia image by C. Sander and durch Urheber

 COMPOSITES

FILLERS and COMPOSITES Blog Post 169 Dt 30 Aug 2014

COMPOSITES – Part 1 Blog Post 156 Dt 17 Aug 2014

INTERFACE OF MATRIX AND FILLER in COMPOSITES Blog Post 180 Dt 10 Sept 2014

MATRIX of COMPOSITES Blog Post 168 Dt 29 Aug 2014

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Glue laminated Large span wood beam at Richmond Olympic Oval, > Wikipedia image by Thelastminute (Duncan Rawlinson)

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WOOD SURFACE FINISHING

WOOD SURFACE FINISHING

Post 472 by Gautam Shah

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Woods’ surfaces have some inherent qualitative characteristics. These relate primarily to the species of wood, broadly the Softwoods and Hardwoods. Other features include presence of oils or resins, food transfer cells, pores, nature of grains (straight, entwined, interlocked, curly or mottled), and local variations of grain colours. Timbers in spite of good seasoning practices show changes in the wood surface during various seasons, stresses and over long term conduct. Wood products are created from young timbers (freshly seasoned) as well as reuse of aged timbers. Wood finishes, are applied on fresh timbers, for conservation of existing status, and for rejuvenation or reformation exercises.

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Soft-wood knot

Wood finishes are broadly of three classes: 1. Finishing done to timbers, 2. Finishing fashioned after a product or item is formed and 3 Finish processes for repairing or reconditioning an existing product.

Clonfert Cathedral Choir Stalls being Ammonia fumed to darken the colour and enhance grains

1 Finishing done to timbers is accomplished with sizing and shaping operations, and include levelling and straightening of the surface.

2 Finishes fashioned after a product or item is formed, are of two types: Finishing with tools, relating to micro-removal of surface material, by grinding, sandpapering, burnishing, singeing, etc. Finishing, a surface, with applique materials, such as surface sealing, putty application, staining and coating. In some instances it may include covering with film, foil or printing.

3 Finish processes for repairing or reconditioning an existing product may involve full or partial removal of existing applied finishes, re-levelling or straightening of an original timber surface to correct deformation of bending, warping, surface irregularities caused by differential shrinking. The removal of existing applied finish is most difficult as it is a matter of conservation, preservation, correction, all in a very limited scale of intervention.

Soft wood planks

Differential wood grain colour

SOFTWOODS are in dull in colour, light in weight and soft grained, but not always inferior in quality. The sap and heart portions are not very different in colour. Soft woods are easy to finish by planing and sanding. A finished surface exposes the tender portions, the remnants of food transfer areas. And these are likely to shrink and decay over a long period, in spite of seasoning. Small amounts of aliphatic compounds, waxy and resinous substances give a fresh wood, a short lasting, smooth feel and slight sheen. Softwoods due the grain structure and the constituents are difficult to stain. Its surface cannot be well sealed and levelled by chalk or oxide pigments, but a coat of very low viscosity NC Lacquer can seal the face.

Pine wood

Softwood articles are difficult to restore, as the wood grains of aged article show uneven settlement. To correct this, entire applique coating must be removed, and surface re-ground, or heavy surface filling by low opacity minerals is required. Old timber articles show very dry surface, which is prone to chipping along the grain.

HARDWOOD Quebracho colorado wooden sleepers of Argentine origin in Uruguay

 HARDWOODS are darker in colour and heavier in weight. In hard woods, the heart portions are fairly distinguishable from the sap portions. On planing and sanding the hardwood surface, intermittent branches of pores, the food transfer areas are clearly visible. The pores are very narrow in width and short in length. The pores on drying tend to shrink in but being fewer and tightly packed by the surrounding fibres, effect of moisture transfer is not very acute as with soft woods. Hardwoods are tough grained and require greater efforts for smoothing, but the finished surface retains its fairness much longer.

Abies grandis (grand FIR) Trunk section

Rough finishes are cheaper, take less time to prepare and require simple tools and techniques. Some rough surfaces give better bondage to preservatives and coatings. Rough surfaces are good for moisture movement but are highly vulnerable to insect and bacterial growth. Rough finishes hide local defects such as stains, knots, ugly grains, fine cracks etc.

Rough or as sawn finish of Hardwood

Smooth finishes are costly, require fine tools and superior techniques. Smooth finish often give poor bondage to preservatives and coatings but one requires much lesser quantity for coverage. Such finishes collect little dirt. Smooth finishes are not as susceptible to bacterial growth as the rough finishes. The timbers for smooth finish should have a fine grain pattern. Heart portions are much better for smooth finish then sap portions. Sap portions may however be finished fairly smooth, provided are immediately covered with moisture proof coating. Hardwoods usually provide smoother finish and of permanent type then soft woods. Woods with resinous or oily substances generally have smooth feel, however, if the substances are reactive or soluble in water or aliphatic solvents, may create problems during coating. Sisam and rosewood have oily or waxy face, which does not allow oil paints or varnish finish. Such woods need to be covered with very thin coatings based on solvent evaporation drying; like nitro cellulose lacquer. Timber surfaces are flame charred or singed to provide slightly darker to black tone to selected areas. The flame is either ‘cool’ capable of depositing carbon, or `hot’ to singe the surface.

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WOOD COMPOSITES

WOOD COMPOSITES

Post 378 ⇒   by Gautam Shah 

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Woods derived from trees and large-trunk plants, consist of timbers, twigs and barks. Woods also include forest-based products, crop wastes, and plant materials like grasses and fibres. Woods have been used for the timbers, for animal feed, as manure and fuel. Many of the wood products have wood in the original form and character, in the re-composed, or derivative form. Wood processing technologies, offer several wood-based products to enhance the peculiar characteristics, overcome the qualitative and sensorial deficiencies, offer new uses, add economic value or ecologically sustain the natural materials.

Wood waste of turnings

Woods are used for constructing geometric or structural compositions, used as filler for forming composites and form the raw materials for many industrial goods. Timbers’ wastes such as very thin or small cuts, chips, shavings, turnings, dust, shavings are used as filler in composites. Leaves are used for manure making or composting. Stems and soft branches yield fiber used for yarn and rope making. Long leaves such as of palms are used for mat weaving, basket making and brooms. Barks and other useless components are compressed and extruded as fuel bricks. Wood derivatives such as its cellulosic matters go through various levels of pulp conversion, and used for boards and casts.

Rice chaffs or husks for particle board making

Wood composites have wood as the filler component. The fillers in the form of could be, Large solids (such as blocks in block-boards), Particulate matter (such as chips, shavings, turning, sanding dusts, farm husks, etc. in particle boards), Sheets (such as for Veneers and plywoods in layered composites), Fibrous materials (for in-fill and reinforcement material in cement and gypsum boards).

Wood and plant products with cellulose as the chief constituents are pulped to produce different grades of materials. This could be soft boards, Hard boards, High, medium and low density (HDF, MDF, etc.) fibre boards. At higher pulping level and with addition of rags it could turn into grey boards, card-boards and paper.

Wood particulate with cement

All wood composites, except the refined cellulosic or pulped formations, require a matrix for bonding of the fillers. The simplest of bonding is mechanical tying. It binds the materials only at selected points, so the filler materials need to have sufficient mass and strength to distribute the stresses. Chemical or glue bonding is the most common method for holding the components. Bonding materials such as adhesives, resins or cementious products are water or solvent based. Polymeric materials are thermosetting or thermoplastic materials and may need heat.

Plywood -a layered composite

Veneer is a thin (as low as 0.6 to 0.8 mm) sheet of wood with uniform thickness, produced by peeling or rotary cut (by rotating a log against a knife), slicing, or by sawing a wood. All parts of a tree such as trunks, round, square or rectangular cut logs, and subterranean part of a trunk with root nodes, and heavier branches, are used for veneer cutting. More than 90 percent of all veneer is rotary cut, but thicker figured wood veneer for furniture and other decorative purposes are sliced. Sawn veneer was considered a wasteful operation, but modern sawing equipments can saw a wood into very thin sections with very little material turning into dust. Some veneer waste is stacked, composed and recut again as veneer. Plywoods are also one form of thick veneers. Veneers form a layered composite. Plywoods are re-composed to form large-span wood beams (20mts) for exhibition halls, malls and departmental stores. These beams are lighter in density and have greater fire-exit time (catching fire and distortion of the structure), compared to a steel beam.

Wood composite beam

Composite wood Bridge

Block boards and Cored plywoods are composite materials with a filler core. Batten or block board and flush doors have a solid or partly filled core of strips of solid woods, which may or may not be glued together. These however, are covered on both sides with sheets of plywood or other composite boards.

Chip boards are entirely made of chips, and other cutting-dressing wastes bonded with an amine resin. Particle boards have particulate matter or agri husks, etc. as the filler, bonded with a resin matrix.

Wood waste or Chip board

Composite boards have a core of polymer latex, styrene or PU foam, encased on both sides with plywoods or other sheets.

Foam cored boards

MDF, HDF, LDF, Soft and Hard-boards are not wood composites, but wood pulp-based products. Mechanical or semi chemical processes are used for pulp preparation. In one process wood or wood waste is reduced to fine size and subjected to a high pressure steam treatment and forced out through a valve to reduce the mass to pulp. In wet felting pulp is cast into sheet form of various thickness, and density is controlled by the pressure. In dry felting process, the pulp is drained, separated and additives are mixed. Additives include glues (1 to 4%), waxes, paraffin, rosin, polymers, colourants, chemicals to improve the resistance to microbes, insects, and fire. Dry felted fiberboard with thermoplastic resin bonding materials are available in low, medium, and high densities. These are extensively used for Panellings and also as a core material for various composites.

Particle board

Hardboard is dry felted Fiberboard with one or both sides finished smooth, available in various densities. The fibres are hot pressed, to form a board bonded by lignin, with small addition of binding agent. Hard boards are available from 3 mm to 12 mm thickness. Tempered Hard boards have one or both face impregnated or coated with a resin to provide better stiffness, wearability and moisture resistance. Hard boards are generally dark in colour due to the use of phenolic bonding media. MDF is fiberboard but with a greater amount of binding agent, almost comparable to a particle board.

Soft-board is very similar to hardboard, with the mass being less cohesive due to the wet felting process. These boards are used for insulation, sound proofing and as tack or pinup boards. Soft-boards with bitumen impregnation were produced for slightly better weather resistance.

Polymer + wood composite board

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ROSEWOOD

Post 376 – by Gautam Shah 

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640px-Topvieuw_of_a_tambura_bridgeRosewood refers to any number of dark red to brown hued woods with darker veins. It is accepted that genuine rosewood belongs to genus Dalbergia. It is known as Brazilian Rosewood, and also as Bahia Rosewood. Its popular name rose-wood derives from the long lasting strong sweet smell and reddish colour. The woods of Dalbergia are now listed as endangered species, and its felling and trading, are banned. The Dalbergia has many subspecies such as Dalbergia nigra, Dalbergia maritima (Madagascar rosewood known as bois de rose), Dalbergia latifolia (East Indian Rosewood or sonokeling wood), Dalbergia oliveri (S.E. Asia Rosewood) and Dalbergia sissoo (also known as Indian rosewood, sissoo or sisam).

 

RosewoodPiecesRosewood has become a generic or representative name for hard dark reddish-purple to brownish coloured woods of tropical regions. No agency regulates, the use of word ‘rosewood, and anyone can use it freely. So we have ‘rosewoods’ of Brazil, Honduras, Jamaica, Africa, Burma, Thailand, China, Nepal and India, differently named as Indian rosewood, African rosewood, and Burmese rosewood or Amboyna wood. Not all woods of genus Dalbergia provide rosewoods. Other woods of in the same family include African Blackwood, Cocobolo, Kingwood, Tulipwood and Australian Rose Mahogany (Dysoxylum fraserianum).

 

Low-back_armchair,_China,_late_Ming_to_Qing_dynasty,_late_16th-18th_century_AD,_huanghuali_rosewood_-_Arthur_M._Sackler_Gallery_-_DSC05918

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Rosewood has denser grain near the core, but its outer sapwood is soft and porous. Rosewood trunks are very large, but squared logs or planks are rarely cut because before the tree reaches maturity, the heartwood begins to decay, making it faulty and hollow at the center.

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WLA_lacma_Herter_Brothers_Parlor_Cabinet

Rosewood is strong and durable than teak. Rosewood is dense so pre-drilling or hole punching is advisable before nailing or screwing. Working with rosewood can dull cutting blades and put a heavy load on power tools. Some varieties of rosewoods have oily grain, which do not allow oil varnish coating or adhesive joining. Rosewood items must be finished with Nitro cellulose lacquer or waxed with little oil. Its lighter colour grains are stained with spirit soluble waxoline red dye (similar to dark tan show polish).

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Falaknuma_Palace_09_-_Dining_table

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Hans Wegner chair in Pompidou, Paris

All rosewoods have dense grain, so take good polish and retain it for long period. Rosewoods are considered ideal material for tool handles (chisels, screw drivers, hammers) door-window handles, wood pegs for joinery, paper weights, scales, rulers, decorative table pieces, agriculture implement, diamond polishing handles, weaving shuttles, silk yarn bobbins, chess sets, musical instruments, billiard cues, weapon handles etc. Rosewood shavings and sanding dust are added to hair-oils as a natural dye. Rosewood veneers and borders are highly valued items. Rosewood allows very thin sections for furniture items such as chairs, teepoys, tables, etc.

Sisam wood

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INDIAN ROSEWOOD

In India best rosewood is called sisam, and is found almost everywhere. Mysore or Karnataka rosewood is of a deep red purple colour with black streaks. Dangs in Gujarat, MP, Nepal border areas with Bihar and UP, and Haryana, provide rosewood of ruddy brown to purplish-brown colour. India padauk or narra wood is usually of red or rose colour, often variegated with yellow, and is hard and heavy. Narra wood is known also as Burmese rosewood, Andaman redwood, and kiabooca wood. A Jacaranda is a tree of Brazil origin with timber of purple to blackish colour, often stained to match sisam for veneer making.

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Sisam in India (or shisham) is known by other names: aguru (Sanskrit), Bombay Rosewood (English), Dalbergia (Arabic), nakku katti (Tamil Nadu), ostindisches Rosenholz, pradu-khaek, pradu-khaek, shinshapa (Sanskrit), shisham (Hindi), shishu (Bengali), shisu (Bengali), sisam (Hindi), sisham (Nepali), sissai (Hindi), sissau (Nepali), sisso (English), sisso (Tamil), sissoo (English), sissoo (Arabic), sissoo (Hindi), sissu (Hindi), sisu (Bengali), sisu (Spanish), sisuitti (Tamil), skuva, sonoswaseso (Javanese), tali, yette (Tamil).

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BURNISHING

BURNISHING

Post 288 ⇒   by Gautam Shah  →

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Burnishing is a material surface finishing process. It polishes and hardens a surface, so that the endowed finish lasts longer. Surfaces that depend on the smoothness for reduced friction, and take lots of wear, need to be burnished. A burnishing rubs the rough surface texture and makes it shinier, but it is not intended as a polishing process. Polishing removes all excess (protruding) materials to level out the surface, whereas Burnishing removes minimum surface material and hardens the surface. It is true that a well polished or a smooth surface takes better burnishing.

Burnishing

Burnishing is mainly a Metal surface alteration process. It is used in various versions for Ceramics, Wood, Leather Paper Cement, Textiles and Artwork. Burnishing occurs on a surface, where another surface sliding on it creates a contact stress which locally exceeds the yield strength of the material. It induces plastic deformation of the surface component, hardens the surface by generating compressive stresses.

Bearing Surface -burnished metal face

Burnishing is not always desirable process for all metal items. It affects the behaviour quality of the surface significantly and often unpredictably. A burnished face, visually seems smoother but with repeated sliding marks grooves over the surface in the sliding direction. Heavy burnishing forces separation of top layer causing peeling of it. Burnishing generates heat which is greater than rubbing or polishing. This excess heat deforms thin body parts. A part deformed due to heavy burnishing, takes greater friction, creating a ‘runaway’ situation where the part fails.

Ceramics burnishing are a treatment in which the green mass of the pot (before drying for baking) is polished and compressed. Compressing the mass and allows excess water to come to the surface, increases the density of the mass and provides a glossy surface. Burnishing is also done after coating the raw item with the slip. As part of surface compaction, sometimes patterns are embossed on the surface. Hard smooth surfaces like wood, bone, glass, metal, or ceramics are rubbed on the surface.

Tripod vessel with lid, Maya culture, Mexico or Guatemala, 4th-5th C, hand-built ceramic with incised decoration and burnished slip, Honolulu Museum of Art

Wood Burnishing is done by rubbing hard grained wood piece along the surface of the wood. Burnishing generates heat, to dry out the surface, melt and fuse the resinous substances or additive substances such as oils, wax etc. Burnished surfaces retain the natural feel (grain and colour) of the wood, and is more natural looking then any coating treatment. Lacquer coated woods are burnished with wool fabrics to gain a natural sheen. Sometimes rubbing compounds that have very fine abrasive grains, wax, oils, lubricants like silicone oil and colouring dyes are used.

Leather Burnishing is used for top and under surfaces as well as edges of leather products. Hard wood pieces are rubbed over leather with or without rubbing materials like oil or wax to achieve a compressed mass and glossy face. The heat also facilitates penetration of rubbing material. The process is also conducted at leather sheet and product formation level. At a leather sheet level-heated roller with pattern compresses the leather. A process, reverse of burnishing is done to produce suede surfaces.

Leather edge finishing

Paper Burnishing is a post paper forming process. It is done to compact the grain-mass and provide sheen, by heavy calendering. Calendering is accompanied by bodying with starch, minerals or resins. It is done to emboss textures or patterns. Photographic mount-boards have such ingrained textures.

Plaster Trowelling -burnishing

Cement Burnishing is done to plasters and cast concrete surfaces. Cement plasters are re-trowelled after the initial setting of the cement. Trowels of wood or metal sheets are rubbed to compress the mass, bring the excess water to the surface and polish it. In case of Tri-mix concrete floors, post setting vibration compacts the surface bringing out the excess water, which is than suctioned out.

Tri-mix concrete -burnishing process

Textile Burnishing is a fabric finishing and texturizing process. Fabrics are hot pressed and passed through rollers. Sized and chemical treated fabrics get a sheen and smoother surface. Fabrics are singed during the process to burn standing or loose fibres and to compact the mass. Shrinking also reduces the mass.

Art-Work Burnishing involves applying colours and than rubbing them to level the surface. The technique was used for Encaustic or wax colour painting. Wax colours were rubbed and polished to achieve a saturated effect. Tempera paintings were also treated or touched with same techniques. Modern day application uses wax crayons or pencils to fill in colours, which are then rubbed with smooth glass or stone. The surface gets warm to melt and fuse the colours.

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WOOD RESOURCES

Post 217 – by Gautam Shah 

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Wood’s appearance, warmth to touch, its ability to be worked with simple inexpensive tools, wide range of tonal hues, grain patterns and textures make it, the most versatile craft material. The only drawback for using wood, is the effect of moisture on its structural properties and its susceptibility to decay. No two pieces of timber are similar, the great variations in structural properties, colour, texture etc., make it suitable for different uses. These wide variations in a quality put the timber to a disadvantage in comparison to many naturally available materials.

Wood products

Wood products

Wood products

Wood products

Trees can be basically classified into two groups – exogenous trees (exogens) and endogenous trees (endogens).

  • Trees may be broadly grouped into exogenous and endogenous trees according to the way in which their stem diameter increases.
  • Endogenous: are trees with inward growth, and have longitudinal fibres such as canes, bamboo, palms etc. Typically it is not possible to see any growth rings in this set of trees.
  • Exogenous: are trees with outward growth (such as additions of annual-seasonal rings), like Conifers (narrow leaves) (pine, fir), Deciduous trees (broad leaves) (teak, rose). These are used as engineering timbers.
Exogenous conifer

Exogenous conifer

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Endogenous plant Bamboo

Endogenous plant Bamboo

Exogenous plants as the name suggests grow outward. The stems are formed by successive additional layer on outside. Timber is essentially derived by the new mass formed in the cambium between the wood and the bark every year. Trees of cold climates and substantial numbers trees of warmer climates are exogenous. Rings in the trunk or branch section, and pith with medullary rays extending outwards to the bark are two distinguishing features of exogenous trees. Exogens yield timber for furniture and construction. Exogenous trees are subdivided into two main classes: broad-leaved trees and needle-leaved trees, or conifers. Broad-leaved Woods generally contain no resins, and the density or weight is greater. They are usually hard, and due to their irregular structure, net yield is lower.

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The other botanical group of endogenous trees or endogens or grow inward from a hard exterior shell or, more commonly, end-wise by the acquisition of a new joint. Endogenous trees grow by forming new fibres within the trunk interspersed with the old fibres. Old endogenous stems have older and harder wood near the surface, whereas younger and softer centre. Timber from these trees has very limited engineering applications. Examples of endogenous trees are Palms, bamboos, canes, etc. These are not broadly useful for furniture or construction work, yet have their specific advantages and uses.

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640px-Thonet_chairs_Wien_museum_Karlplatz

Commercial timbers of exogenous trees are classified as softwoods and hardwoods, though a very misleading nomenclature. Softwoods are timbers obtained from conifers, growing above certain altitude, and are supposed to be soft and lighter in colour. Hardwoods, are timbers that originate from the mainland and tropical areas are supposed to be hard and darker in colour. Many softwoods, though, are much harder and often of darker in shades than some of the hardwoods. Inversely many hardwoods are fairly soft and lighter in colour than some of the softwoods. Botanical names and commercial names of trees or timbers do not provide a true picture. There are multiple botanical names for the same specie adding to the confusion. Same timber is likely to be differently known commercially in various parts of the world.

Thanjavur_Palace'

Thanjavur Palace India

Timber is a very precious commodity. It takes decades to grow a commercially viable timber tree. Deforestation has become a prime issue from ecological points of view. Several countries have banned or severely curtailed and controlled the export of timber. Similarly many countries have banned import of timber to limit deforestation world wide. Many governments and local authorities discourage timber structures and other uses of timber. Government of India has enforced conditions, so that usage of timber as doors and windows and other structural purposes are nearly banned, in government schemes. Similar conditions are likely to be followed by state governments also. So over the years use of timber is likely to be severely curtailed not only due to legislation but also its difficult availability and consequent upward pricing.

Wood products

Wood Composite products

Timber grown in planned plantations is of consistent variety due to standard or a singular source of seedling or genetic derivation and grown in very controlled conditions. These results in trees with identical grain, colour and texture, belying the natural variations associated with woods.

wicker-furniture

Wood replacement products are of broadly two types. Wood-based composites such as plywood, block boards, chip and particle boards are likely to remain available, but only for a while. The availability of such products is also going to taper off in future. Wood ‘look-a-like’, make-believe, or pseudo wood products made of polymeric composites, painted, printed or layered materials are in the market.

Unlike a metal or plastic, wood is inherently a replenish-able resource, provided production and use are controlled and matched.

 

 

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