Prospect : List of Timber Properties

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Rosanna Walsh
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1 Prospect : List of Timber Properties Characteristic Descriptors Details/Conditions Definition tree feature tree height (m) 0 - < < < < < < <70 70 and above The total height of the standing tree in metres. bole length (m) 0 - < < < < <50 50 and above trunk diameter (cm) 0 - < < < < < < < and above The length of the main trunk or stem of the tree in metres. The diameter or girth of the tree at breast height (1.37m above the ground, or 1.37m above any buttress) measured in centimetres. bole/stem form end/splitting on felling straight misshapen cylindrical fluted buttressed not buttressed other very susceptible may occur rare/absent The general shape or form of the main stem. The susceptibility of the bole or stem to split longitudinally during the process of felling. bark width (mm) 0 - <5 5 - < < < < < <50 50 and above The average thickness of the bark, usually measured at breast height. sapwood width (cm) 0 - <5 5 - < < < <25 25 and above The width (thickness) of the sapwood, where it is visibly distinct from the heartwood. brittleheart main heartwood colour frequent/extensive rare or absent/sparse in amount appearance/physical characteristics white / cream yel / golden-yel / orange pale brown brown dark brown pale red / pink red dark red reddish brown ish / greyish purple black The extent of the occurrence of brittleheart (brittleness) found in the heartwood of certain species. The predominant colour of the heartwood after drying. other heartwood colour white / cream yel / golden-yel / orange pale brown brown dark brown pale red / pink red dark red reddish brown ish / greyish purple black Secondary or other heartwood colour after drying, including streaks, bands, stripes etc. sapwood colour light-induced colour change (interior) same as heartwood paler than heartwood well defined white / yel pinkish other colour darker lighter Sapwood characteristics after drying. The change in heartwood colour caused by light during internal (indoor) use.

2 deposits whitish deposits in vessels yelish deposits in vessels stone/gum aggregates gum/resin exudation growth features of the wood gum/resin streaks latex or other ducts included phloem The occurrence of gums and mineral deposits in the structure of the wood. The occurrence of generally undesirable growth features of the wood. silica present <0.1% wt/od wt wood % >0.5% The extent of silica deposits in the heartwood. grain straight wavy spiral interlocked other The alignment of cells relative to the axis of the tree or the longitudinal edge of an individual piece of sawn timber. figure growth ring stripe ripple mottle dimple burr ray irregular colour other The distinctive ornamental markings on the longitudinal surface of wood as a result of the arrangement of its constituent tissues, irregular colouration, defects or the nature of the grain. figure (occurrence) very fine & distinct distinct weak The intrinsic quality of the figure. texture lustre fine fine/ /coarse coarse pronounced lustrous ly lustrous dull Structural characteristics of wood as revealed by touch or reaction to cutting tools. (Largely determined by distribution and size of the various cells). The reflective properties of cell walls before any finish is applied. toxicity non-toxic respiratory effects dermatitic effects poisonous unspecified toxicity A characteristic that provides an indication of the reactive effects which may arise when handling or working a wood. staining properties non-staining coloured water-soluble extract reacts with Fe to discolour wood other staining characteristics Extractives in wood which react, usually in the presence of water, to cause discolouration of the wood or adjacent materials. corrosive properties non-corrosive reacts with metals density (kg/m 3 ) basic air-dry basic air-dry basic air-dry basic air-dry basic air-dry basic air-dry basic air-dry basic air-dry basic air-dry >1000 basic >1200 air-dry movement in service shrinkage - radial shrinkage - tangential shrinkage - volumetric stable not stable/prone to move very fairly very fairly very fairly movement/shrinkage characteristics <3% 3-4.5% >4.5% experiment reputation up to 2% up to 3% % % % % % % >3.5% >6.0% to 12% m.c. to o.d. up to 3% up to 5% % % % % % % >6.0% >9.5% to 12% m.c. to o.d. up to 5% up to 8% % % % % % % >9.5% >15.5% to 12% m.c. to o.d. The corrosive action when a timber comes into contact with metal, such as screws, nails, bolts and plates. The air dry density of wood at 12-15% moisture content (kg/m 3 ) related to basic density (ovendry weight, volume). Movement records dimensional stability subsequent to drying. It is calculated as the sum of the percentage radial and tangential changes consequent upon a change in relative humidity from 90% to 60%. Shrinkage that occurs perpendicular to the growth rings, it is approximately proportional to moisture loss. Radial shrinkage is roughly half that of tangential shrinkage. Shrinkage that occurs perpendicular to the grain and parallel to the growth rings. Volumetric shrinkage is ly less than the sum of axial, radial and tangential shrinkage.

3 mechanical characteristics maximum crushing strength (parallel to grain) modulus of rupture/ bending strength modulus of elasticity/ bending stiffness toughness - total work toughness - work to maximum load toughness - hammer drop toughness - pendulum <10 N/mm 2 <20 N/mm >62 >85 12% to 15% m.c. <32 N/mm 2 <50 N/mm >114 >175 12% to 15% m.c. <8.6 kn/mm 2 <10 kn/mm >17.5 > % to 15% m.c. <0.130 mmn/mm >0.440 <0.070 mmn/mm 3 <0.085 mmn/mm >0.180 > % to 15% m.c. <0.60 m >1.60 <20.3 J >71.2 The maximum compressive strength of the specimen parallel to the grain. The est stresses in the outermost fibres of the wood when the beam breaks under the influence of a load. The linear relationship between stress and strain within the elastic range of a material, providing an indication of stiffness. The energy required to cause complete failure in a beam when the load is applied rapidly. Work to maximum load represents the ability of the specimen to absorb shock with some permanent deformation. A hammer of a given weight is dropped on a beam from successively increasing heights until rupture occurs. The height of the maximum drop that causes failure represents the ability of wood to absorb shocks that cause failure beyond the proportional limit. A pendulum weight is progressively raised and released until it causes failure. hardness (Janka side grain) very soft soft hard very hard <2500 N <3000 N >10000 > % to 15% m.c. The load required to imbed a 11.3mm diameter hardened steel ball into the sample surface to one half the diameter of the ball. shear(parallel to grain) <6.0 N/mm 2 <9.0 N/mm >14.5 >22.0 The measure of the resistance of the timber to shearing, tests being made in both the tangential and radial plane. 12% to 15% m.c. natural durability very durable durable ly durable non durable perishable wood staining fungal attack resistant sapwood susceptible heartwood susceptible Pinworm attack beetle) (ambrosia unusual or absent commonly present present in standing tree attack of felled log occurrence in heartwood durability characteristics (c) years years av. dry wt. loss % >25 >10 nil or negligible 15-<25 5-<10 <5 10-<15 2-<5 5-<10 5-<10 1-<2 10-<30 <5 <1 >30 temperate tropical laboratory test (c) observation/reputation The resistance of timber to fungal degradation and insect attack. The resistance or susceptibility of sapwood and heartwood to the staining effects of fungal attack. Damage caused by one of a group of beetle belonging to the Family Platypodidae and some Genera of Scolytidae.

4 Powder post attack (Lyctid resistantsusceptible Damage to hardwood and softwood & Bostrychid) by beetles of the Families Lyctidae and Bostrychidae. termite attack (Isoptera) resistantly resistantsusceptible Damage caused by insects of the Order Isoptera. Marine borer attack amenability to preservation (heartwood) amenability to preservation (sapwood) drying (rate) drying (ease) kiln drying rate( to 12% m.c.) resistantly resistantsusceptible permeable ly resistant resistant extremely resistant permeable ly resistant resistant extremely resistant fast s rapid fairly rapid rather s s kiln schedule UK=A US=T2D4/T2D3 Fr=1 UK=B US=T2C2/T2C1 Fr=2 UK=C US=T3C2/T3C1 Fr=3 UK=D US=T3D2/T3C1 - UK=E US=T6D2/T3D1 Fr=5 UK=F US=T6D4/T3D3 Fr=6 UK=G US=T8B3/T5B1 - UK=H US=T10D4S/T8D3S Fr=7 UK=J US=T10D5S/T8D4S Fr=4 UK=K US=T13C4S/T11D3S - UK=L US=T14C6S/T12C5S - UK=M - - drying degrade - surface checking drying degrade - end splitting field tes laboratory test observation/reputation salt water test observation/reputation tropical waters temperate waters permeability characteristics complete penetration by preservative lateral penetration 6-18mm lateral penetration 3-6mm effectively untreatable complete penetration by preservative lateral penetration 6-18mm lateral penetration 3-6mm effectively untreatable drying characteristics air drying kiln drying air drying kiln drying (c) <10 days <20 days <30 days >28 >56 >84 up to 32mm thickness 33 to 63mm thickness >63mm thickness (c) Damage caused in marine or brackish water by marine molluscs and marine crustaceans. The extent to which heartwood can be impregnated with preservatives under pressure to protect against fungal, insect or marine attack. The extent to which sapwood can be impregnated with preservatives under pressure to protect against fungal, insect or marine attack. The rate at which timber dries from a condition. The ease or y with which timber can be dried from a condition. The time in days to kiln dry timber from to 12% moisture content. Equivalent kiln schedules used in the U.K. (United Kingdom), U.S. (United States of America), and Fr (France). Separation of wood fibres along the grain forming a crack or fissure that does not penetrate through the timber from one surface to the other. Split at the end of a log or piece. drying degrade - collapse/honeycomb drying degrade - cup Collapse is the flattening or buckling of cells during drying which become manifest in excessive or uneven shrinkage. Honeycomb is the separation of the fibres in the interior of a piece induced by drying stresses. Curvature of a piece of timber across the width of the face. drying degrade - spring/bow drying degrade - twist/warp Bow: curvature of a piece of timber lengthwise in a plane normal to the edge, Spring: curvature of a piece of timber lengthwise in a plane normal to the face. Spiral distortion of a piece of timber lengthwise. drying degrade - knots splits/loosening The splitting or loosening of knots during drying. resin/gum exudation on drying absent present Movement of mobile extractives (gums and resins) which occur when timber is dried as ambient temperatures increase. sawing - general () sawing characteristics The ease or y with which a timber can be sawn when. sawing - general (dry) The ease or y with which a timber can be sawn when air dry (12-15% moisture content).

5 mild sawing - blunting effect () The effect of a timber on the performance of a saw when the timber is. sawing - blunting effect (dry) mild The effect of a timber on the performance of a saw when the timber is dry. machining - general machining - blunting effect fairly machining characteristics The ease or y with which a timber can be machined. The effect of a timber on the performance of a machine when the timber is processed. planing (ease) planing (finish) mortising (ease) mortising (finish) moulding (ease) moulding (finish) turning (ease) turning (finish) boring recessing & routing (ease) recessing & routing (finish) steam bending very very <150 mm >750 radius of curvature supported radius of curvature not supported The ease or y with which a timber can be machined planed. timber is planed. The ease or y with which a mortise can be cut in a timber either by hand or with a machine. timber is mortised. The ease or y with which a timber can be shaped. timber is moulded. The ease or y with which a timber can be machined on a lathe. timber is machined on a lathe. The ease or y with which a timber can be bored perpendicular to the grain. The ease or y with which a timber can be slotted, rebated or routed. The finish achieved when a timber is slotted, rebated, or routed. The curvature to which a 1 inch (25mm) thick sample may be steam bent with an expectation of a 5% failure rate. nailing (ease) possible if prebored fastening characteristics The ease or y of nailing a timber. nailing (hold) The tenacity with which a timber holds a nail. screwing (ease) possible if prebored The ease or y of screwing a timber. screwing (hold) The tenacity with which a timber holds a screw. resistance to splitting (nail & screw) excellent fair very The resistance of a timber to splitting when nailed or screwed. gluing (solid wood) surfacing characteristics The ease or y with which a timber can be glued. finishing - general The general quality of the finished surface. sanding (ease) The ease or y with which a timber can be finished using a paper or cloth backed abrasive.

6 sanding (finish) The quality of the surface finish obtained when using a paper or cloth backed abrasive. staining painting requires filling requires filling be uniformly stained, using either a water or spirit based stain, and the quality of the resulting stained surface. be painted and the quality of the finished surface. varnishing requires filling be varnished and the quality of the finished surface. polishing requires filling be polished, e.g. French polished, and the quality of the finished surface. veneer - bolt preparation veneer- ease of cutting veneer - drying degrade veneer - gluing steaming required no steaming needed ly no degrade - dries flat/no split / - buckles/splits / - collapse +b/s veneer production characteristics rotary cutting slicing uf resin pf resin other resin Treatment of a timber in order for it to produce an acceptable veneer. The ease or y with which a bolt or flitch of timber can be peeled or sliced. The extent of degrade, typically splits and distortion, of a veneer on drying. The ease or y with which a veneer of a timber can be glued and the resulting tenacity of the bond.

Kapur (Dryobalanops Aromatica)

Kapur (Dryobalanops Aromatica) Botanical Name: Other Common Names: Dryobalanops aromatica Kapur, Borneo camphorwood, Kapor, Kapoer, Keladan, Borneo teak, Mahoborn teak Common Uses: Boat building, Construction,