Tropical wood · Africa
Brown Sterculia wood
Brown Sterculia (Sterculia rhinopetala, family Sterculiaceae) is a tropical timber from Africa. Dry, its Janka hardness is 1,810 lbf (8,051 N), and air-dry it weighs about 50 lb/ft³ (801 kg/m³). The figures are from the USDA Forest Products Laboratory's Tropical Timbers of the World, pp. 511–512.
Other names, by country: Wawabima (Ghana), Lotofa (Kvory Coast), Aye (Nigeria).
Key numbers
- Janka hardness, dry
- 1,810 lbf (8,051 N)
- Green: 1,410 lbf (6,272 N)
- As printed: “Janka side hardness 1,410 lb for green and 1,810 lb for dry material.”
- Air-dry density
- 50 lb/ft³ (801 kg/m³)
- Basic specific gravity
- 0.64 oven-dry weight, green volume
- As printed: “Basic specific gravity (ovendry weight/green volume) about 0.64; air-dry density 50 pcf.”
- Shrinkage, green to 12% moisture content
- 9.5% tangential
- Radial 5.0%
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 | 12,600 psi (87 MPa) | 1.56 million psi (10.8 GPa) | 6,170 psi (43 MPa) |
| 12% MC | 21,000 psi (145 MPa) | 2.04 million psi (14.1 GPa) | 10,100 psi (70 MPa) |
| 12% MC | 21,300 psi (147 MPa) | — | 10,300 psi (71 MPa) |
A dash means the sheet prints no value; none is filled in.
What the data sheet says
- Color, grain and texture
- Heartwood pale to deep reddish-brown; sharply demarcated from the 2-in.-wide straw-colored sapwood. Texture rather coarse; grain straight to somewhat interlocked; slight bitter taste but no odor; numerous high rays produce an attractive figure when quartersawn.
- Working properties
- Saws rather woolly with a tendency to spring, however works satisfactorily with hand and machine tools, tends to split on nailing, glues well, stains and polishes well but requires filler, has moderate steam-bending properties.
- Durability
- Heartwood has only moderate durability and moderately resistant to termite attack; sapwood liable to stain and powder-post beetle attack.
- Uses
- Heavy construction work where high durability is not required, tool handles, furniture components, flooring.
- Where it grows
- Lowland rain forests and savanna forests of Nigeria, Ghana, and Ivory Coast.
Quoted from Tropical Timbers of the World, pp. 511–512, a USDA Forest Products Laboratory work in the public domain.
Work it out for your project
- Rank woods for furniture with the species picker
Weigh brown Sterculia against other woods on hardness, weight, movement and color, every figure from the Wood Handbook.