Tropical wood · Africa
Dahoma wood
Dahoma (Piptadeniastrum africanum, family Leguminosae) is a tropical timber from Africa. Dry, its Janka hardness is 1,540 lbf (6,850 N), and air-dry it weighs about 43 lb/ft³ (689 kg/m³). The figures are from the USDA Forest Products Laboratory's Tropical Timbers of the World, pp. 485–486.
Other names, by country: Mbeli (Liberia), Dabéma (Ivory Coast), Dahoma (Ghana), Agboin, Ekhimi (Nigeria), Atui (Cameroon), Bokungu (Zaire), Mpewere (Uganda).
Key numbers
- Janka hardness, dry
- 1,540 lbf (6,850 N)
- Green: 1,320 lbf (5,872 N)
- As printed: “Janka side hardness 1,320 lb for green and 1,540 lb for dry material.”
- Air-dry density
- 43 lb/ft³ (689 kg/m³)
- Basic specific gravity
- 0.56 oven-dry weight, green volume
- As printed: “Basic specific gravity (ovendry weight/green volume) 0.56; air-dry density 43 pcf.”
- Shrinkage, green to oven-dry
- 8.7% tangential
- Radial 3.9%, volumetric 12.5%
One source: USDA Forest Products Laboratory, Tropical Timbers of the World (Chudnoff, 1979 edition), the only published source read for this wood
Strength
Bending strength is the modulus of rupture (MOR); stiffness is the modulus of elasticity (MOE); crushing strength is compression parallel to the grain. The sheet collects these from published tests: it prints 3 data sets, from different tests and sources, so they can differ widely; all are shown, in the sheet's order, each at the moisture content printed beside it, never restated as 12%.
| Moisture | Bending strength (MOR) | Stiffness (MOE) | Crushing strength |
|---|---|---|---|
| Green | 11,000 psi (76 MPa) | 1.43 million psi (9.9 GPa) | 5,320 psi (37 MPa) |
| 12% MC | 15,800 psi (109 MPa) | 1.62 million psi (11.2 GPa) | 8,520 psi (59 MPa) |
| 12% MC | 16,000 psi (110 MPa) | 1.79 million psi (12.3 GPa) | 8,250 psi (57 MPa) |
A dash means the sheet prints no value; none is filled in.
What the data sheet says
- Color, grain and texture
- Heartwood light to golden-brown; sapwood 2 in. wide, grayish to pale straw, distinct. Texture coarse; grain broadly interlocked producing an attractive ribbon figure; moderate luster; unpleasant odor when freshly cut and may return if timber is rewetted; sawdust may irritate skin and mucous membranes; may stain if in contact with iron under moist conditions.
- Working properties
- Works well, blunting of knife edges most pronounced in sawing, a cutting angle of 15 degrees is suggested for planing knives to minimize tearing of interlocked grain, nailing and gluing satisfactory, moderate wood-bending characteristics.
- Durability
- Heartwood is rated as durable, reported to be resistant to termite attack in West Africa but only moderately so in South Africa.
- Uses
- Heavy construction, wharf decking, flooring.
- Where it grows
- Tropical West Africa from Senegal to Angola and across the Congo region to Uganda. Found in mixed deciduous and evergreen forests, often stands as a single tree on farmland.
Quoted from Tropical Timbers of the World, pp. 485–486, a USDA Forest Products Laboratory work in the public domain.
Work it out for your project
- Rank woods for flooring with the species picker
Weigh dahoma against other woods on hardness, weight, movement and color, every figure from the Wood Handbook.