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Clicking any heading in the main data area (at right) will scroll the page back to this top position. Use the following links to jump to the associated section in the main data. Blunting Effect Boring Carving Common Names Common Uses Countries of Distribution Cutting Resistance Distribution Overview Drying Defects Ease of Drying Environmental Profile Family Name Gluing Grain Heartwood Color Luster Mortising Moulding Movement in Service Nailing Natural Durability Numerical Data Odor Planing Polishing Product Sources References Regions of Distribution Resistance to Impregnation Response to Hand Tools Routing & Recessing Sanding Sapwood Color Scientific Name Silica Content Staining Steam Bending Strength Properties Texture Toxicity Trade Name Tree Size Turning Scientific Name Gluta sp. Trade Name Rengas Family Name Anacardiaceae Common Names Black varnish tree, Borneo rosewood, Gluta, Lingas, Rak, Rengas, Straights mahogany, Thayet-thitsi, Thitsi Regions of Distribution Oceania and S.E. Asia Countries of Distribution  [VIEW MAP] India, Myanmar, Philippines, Thailand Common Uses Cabinetmaking, Decorative veneer, Furniture , Joinery, Specialty items, Turnery, Veneer Environmental Profile Status unsure as a result of insufficient information Data source is World Conservation Monitoring Center Distribution Overview Indo-Malaysian region (including Thailand and India), reaching into Indonesia and the Philippines, as well as Madagascar. Found in lowland forests and inland peat swamp forests and hills. Heartwood Color White Brown Bright cherry-red The heartwood is bright red, with alternating bands of darker color, which produce a figure similar to that on the surface of flat-sawn Douglas-fir. The heartwood is also sometimes streaked with yellow. Prolonged exposure tones down the vivid red color to a warm, mahogany red-brown color, but it tends to fade with exposure to strong sunlight Sapwood Color White White to yellow Pale brown Clearly differentiated from the heartwood The sapwood is described as almost white to light pink brown in color, sometimes streaked with yellow. It is rather wide in most species, up to 3 inches in mature trees, and is often sharply demarcated from the heartwood Grain Even Figure Straight Irregular Straight to irregular Texture Fine Even or uniform Uniform Medium Medium coarse to coarse Fine Even textured Luster Low Low Natural Durability Perishable Non-durable Non-resistant to marine borers Non-resistant to powder post beetles Non-resistant to termites Somewhat susceptible to attack by termites Sapwood susceptible to attack by powder post beetles Heartwood has moderate resistance to decay The standing tree is subject to ambrosia-beetle attack Odor Has an odor No specific smell or taste Silica Content Likely to have significant impact on machining Contains silica Toxicity Some toxic effects Sap in the bark and wood is highly irritating to some individuals. The sap is reported to persist even after the wood is air-dried, and may seep through polished surfaces. Drying Defects Splitting Checking Warping and checking are slight, and shrinkage is rather low. Ease of Drying Reconditioning Treatement Little degrade Dries slowly with little degrade Tree Size Bole length is 10-20 m Trunk diameter is 100-150 cm Boles are reported to vary from cylindrical to irregular in form Product Sources Several species in the Melanorrhoea and Gluta genera are mixed and marketed together under the trade name Rengas. Blunting Effect Cutting edges are dulled rapidly and severely Dulling of cutting edges can be rather severe because of silica content Boring Fairly easy to very easy Carving Fairly Easy to Very Easy Cutting Resistance Easy to saw Cutting Resistance with dry wood is difficult Cutting resistance is variable Conversion in the green condition has been suggested since seasoned wood is difficult to saw. Degree of difficulty varies with species Gluing Fair to Good Results Mortising Fairly Easy to Very Easy Moulding Fairly Easy to Very Easy Movement in Service Unstable with Poor Stability - Large Movement Stable Dimensional stability is very good, and seasoned wood is reported to hold its shape well in use Nailing Pre-Boring Recommended Poor to Very Poor Results Planing Fairly Easy to Very Easy Fair to Good Results Very Good to Excellent Results Yields smooth surfaces Responds well to machining Cutting edges must be sharpened frequently Rengas responds well to machine tools, but it tends to dull cutting edges rapidly because of silica content. The wood can be dressed to a smooth finish Resistance to Impregnation Permeable sapwood Permeable heartwood Sapwood is permeable The heartwood is unresponsive to preservative treatment, but the sapwood is permeable and can be readily treated. Response to Hand Tools Responds Readily Easy to Work Yields a smooth surface with hand tools Routing & Recessing Fairly Easy to Very Easy Sanding Fair to Good Results Very Good to Excellent Results Turning Fairly Easy to Very Easy Steam Bending Unsuitable Poor to Very Poor Results Fairly Difficult to Very Difficult Unsuitable The timber is unsuitable for steam bending because of excessive resin exudation Polishing Fair to Good Results Takes a high finish The timber takes a high polish and does not require excessive filling. Black sap in the wood has a tendency to seep through polished surfaces which may necessitate repolishing. Repolishing after sufficient time interval (2 to 3 years suggested) takes care of the problem. Staining Fair to Good Results Fairly Easy to Very Easy Strength Properties Max. crushing strength = low Heavy Bending strength (MOR) = low Rengas is heavy and dense. It has low strength properties in bending and crushing, and is very low in stiffness and resistance to shock loads. Numerical Data Item Green Dry English Bending Strength 9998 12833 psi Density 46 lbs/ft3 Hardness 1686 lbs Maximum Crushing Strength 2613 8212 psi Stiffness 1671 1877 1000 psi Specific Gravity 0.58 Weight 45 37. lbs/ft3 Radial Shrinkage 3 % Tangential Shrinkage 5 % Item Green Dry Metric Bending Strength 702 902 kg/cm2 Density 737 kg/m3 Hardness 764 kg Maximum Crushing Strength 183 577 kg/cm2 Stiffness 117 131 1000 kg/cm2 Specific Gravity 0.58 Weight 721 592. kg/m3 Radial Shrinkage 3 % References Chudnoff, M.,1984,Tropical Timbers of the World,U.S.A. Department of Agriculture, Forest Service, Forest Products,Laboratory, Madison. Desch, H. E. 1957. Manual of Malayan Timbers - Volume I. Malayan Forest Records, No. 15. Malaya Publishing House Ltd., Singapore. Desch, H. E. 1957. Manual of Malayan Timbers. Malayan Forest Records, 28(30):315-318. Keating, W.G., Bolza, E.,1982,Characteristics properties and uses of timbers. South East Asia, Northern,Australia and the Pacific,C.S.I.R.O. Div. Chemical Technology,Inkata Press,1 Kloot, N. H. and E. Bolza. 1961. Properties of Timbers Imported into Australia. Technological Paper No. 12. Division of Forest Products, Commonwealth Scientific & Industrial Research Organization, Melbourne, Australia. Limaye, V.D. 1954. Grouping of Indian Timbers and their Properties, Uses and Suitability. Indian Forest Records, New Series. Timber Mechanics, Vol. 1, No. 2, Forest Research Institute, Dehra Dun, India. Limaye, V.D. and B.R. Sen. 1953. Weights and Specific Gravities of Indian Woods. Indian Forest Records, New Series. Timber Mechanics, Vol. 1, No. 4, Forest Research Institute, Dehra Dun, India. Lincoln, W.A. 1986. World Woods in Color. Linden Publishing Co. Inc., Fresno, California. WCMC. 1992. Conservation Status Listing - Trees and Timbers of the World. World Conservation Monitoring Center-Plants Programme, Cambridge, CB3 ODL, United Kingdom.