Tropical wood · Southeast Asia and Oceania
Black Wattle wood
Black Wattle (Acacia mollissima, family Leguminosae) is a tropical timber from Southeast Asia and Oceania. Dry, its Janka hardness is 1,750 lbf (7,784 N), and air-dry it weighs about 45 lb/ft³ (721 kg/m³). The figures are from the USDA Forest Products Laboratory's Tropical Timbers of the World, pp. 543–544.
Other names, by country: None.
Key numbers
- Janka hardness, dry
- 1,750 lbf (7,784 N)
- Green: 1,280 lbf (5,694 N)
- As printed: “Janka side hardness 1,280 lb for green material and 1,750 lb at 12% moisture content.”
- Air-dry density
- 45 lb/ft³ (721 kg/m³)
- Basic specific gravity
- 0.60 oven-dry weight, green volume
- As printed: “Basic specific gravity (ovendry weight/green volume) 0.60; air-dry density 45 pcf.”
- Shrinkage, green to oven-dry
- Not printed
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 2 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 | 11,550 psi (80 MPa) | 1.62 million psi (11.2 GPa) | 5,170 psi (36 MPa) |
| 12% MC | 17,500 psi (121 MPa) | 2.08 million psi (14.3 GPa) | 8,800 psi (61 MPa) |
A dash means the sheet prints no value; none is filled in.
What the data sheet says
- Color, grain and texture
- Heartwood pale brown with a pinkish tinge; not sharply demarcated from the sapwood. Grain commonly interlocked; luster medium; texture moderately fine and uniform; without distinctive odor or taste.
- Working properties
- No data available on machining characteristics but tests in Australia indicate its suitability for cutting into veneer.
- Durability
- Heartwood nondurable; sapwood. vulnerable to lyctus beetle attack.
- Uses
- Mining props, flooring parquet and strips, hardboard. Mainly cultivated for the rich tannin content of the bark, reaching 40 to 50%.
- Where it grows
- Native to Australia but extensively planted in East and South Africa and elsewhere.
Quoted from Tropical Timbers of the World, pp. 543–544, 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 black Wattle against other woods on hardness, weight, movement and color, every figure from the Wood Handbook.