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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 Comments Common Names Common Uses Countries of Distribution Cutting Resistance Family Name Grain Heartwood Color Luster Nailing Natural Durability Numerical Data Planing Polishing References Regions of Distribution Resistance to Impregnation Response to Hand Tools Sapwood Color Scientific Name Screwing Staining Steam Bending Strength Properties Texture Trade Name Tree Identification Tree Size Veneering Qualities Scientific Name Neoboutonia macrocalyx Trade Name Chebakwa Family Name Euphorbiaceae Common Names Chebakwa, Dundu, Kibatwa, Kipsebuet, Mahuhu, Mubohu, Muhaa, Mutundu, Mutundu-tundo, Mutuntuki, Sabaitet, Shawa Regions of Distribution Africa Countries of Distribution  [VIEW MAP] Congo, Kenya, Mozambique Common Uses Boat building (general), Boxes and crates, Cabinetmaking, Carvings, Food containers, Fuelwood, Furniture, Joinery, Light construction, Particleboard, Plywood corestock, Plywood, Pulp/Paper products, Sporting Goods, Toys Heartwood Color Yellow Red Brown Orange Pink White to cream Greenish to greyish Sapwood Color Red Yellow Same as heartwood Grain Even Straight Straight Texture Fine Coarse Luster Medium High Natural Durability Durable Perishable Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Non durable Heartwood is susceptible to wood staining fungal attack Susceptible to marine borer attack Susceptible to attack from termites (Isoptera) Tree Identification Bole/stem form is straight Bole/stem form is cylindrical Tree Size Tree height is 10-20 m Tree height is 20-30 m Tree height is 30-40 m Comments General finishing qualities are rated as poor Blunting Effect Blunting effect on machining is slight Cutting Resistance Easy to saw Nailing Nails hold poorly Easy to nail Planing Fairly Difficult to Very Difficult Very Good to Excellent Results Fair to Good Results Planes to a poor finish Resistance to Impregnation Sapwood is permeable Heartwood is moderately resistant Response to Hand Tools Easy to Work Easy to machine Screwing Poor results Easy to screw Veneering Qualities Good gluing qualities There is slight to moderate drying degrade and the potential for buckles and splits Suitable for peeling No steaming needed during bolt preparation. Moderately easy to veneer Steam Bending Good Polishing Satisfactory results Staining Finish is generally satisfactory Strength Properties Density (dry weight) = 23-30 lbs/cu. ft. Shrinkage, Tangential = very small Shrinkage, Radial = very small Modulus of Elasticity (stiffness) = very low Max. crushing strength = low Density (dry weight) = 15-22 lbs/cu. ft. Bending strength (MOR) = low Shrinkage, Tangential = small Shrinkage, Radial = small Shearing strength (parallel to grain) = very low Shearing strength (parallel to grain) = low Numerical Data Item Green Dry English Bending Strength 6111 9589 psi Density 24 lbs/ft3 Maximum Crushing Strength 2139 3916 psi Shearing Strength 1221 psi Stiffness 1017 1199 1000 psi Weight 24 20 lbs/ft3 Radial Shrinkage 2 % Tangential Shrinkage 5 % Item Green Dry Metric Bending Strength 429 674 kg/cm2 Density 384 kg/m3 Maximum Crushing Strength 150 275 kg/cm2 Shearing Strength 85 kg/cm2 Stiffness 71 84 1000 kg/cm2 Weight 384 320 kg/m3 Radial Shrinkage 2 % References Bolza, E., Keating, W.G.,1972,African Timbers - the Properties, Uses and Characteristics of 700 Species,C.S.I.R.O. Div. of Building Research Dale, I.R., Greenway, P.J.,1961,Kenya Trees and Shrubs,Buchanans Kenya Estates Ltd. Nairobi Hatchards London Eggeling, W.J.,1940,Indigenous Trees of Uganda,Govt. Printer Entebbe Uganda France - C.T.F.T./C.T.B.,1982,Guide pour le Choix des Essences Deroulables-pour la fabrication du,contreplaque,C.T.F.T./C.T.B. France Murira, K.,1984,Natural Durability Tests of Tanzanian Timbers 1955 - 1982,Tanzania Forestry Research Institute, Timber Utilisation Research Centre,,Moshi. Wimbush, S.H.,1950,Catalogue of Kenya Timbers,Govt. Printer Nairobi Kenya