Sucupira
Diplotropis purpurea
Sucupira measures 2,140 lbf on the Janka scale, 66% harder than northern red oak.
- Only nine of the 155 woods are stiffer.
- Drying barely changes its hardness: from 1,980 lbf green, it gains only 8% by 12% moisture, against a median of 31%.
- Its stiffness is 44% above the median for imported woods.
- Pignut hickory has exactly the same Janka figure.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
SucupiraImported woods medianOther woods
Stiffness
2.87 M psi19.8 GPa10th stiffest of 15544% above the imported woods median0.54 M psi4.06 M psiDensity
0.7812th heaviest of 15528% above the imported woods median0.250.96Bending strength
20,600 psi142.0 MPa14th strongest of 1554,300 psi29,900 psiJanka hardness
2,140 lbf9,519 N16th hardest of 15516th of 65 imported woods; 65% above the imported woods median240 lbf3,680 lbfCupping tendency
1.5228th lowest of 1551.092.90Shrinkage across the face
7.0%radial 4.6%45th lowest of 1553.5%12.7%
How much it moves
The two directions move almost alike (T/R 1.52), so flatsawn and quartersawn boards differ by only 0.14 in.
0.42 in.
off a 6-inch flatsawn board, green to oven-dry
- Tangential
- 7.0%
- Radial
- 4.6%
- Volume
- 11.8%
- T/R ratio
- 1.52 (28th most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- Kempas
20% softer · 9% lighter · shrinks 0.4 points more across the face
- Bubinga
26% harder · 9% lighter · shrinks 1.4 points more across the face
- Goncalo alves
1% harder · 8% heavier · shrinks 0.6 points more across the face
Woods of similar hardness
The eight nearest on the Janka scale, lbf.
Laboratory values
Its most unusual laboratory figure is crushing strength along the grain: 7th highest of the 154 woods with a published value.
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Compression parallel to grain | 8,020psi | 12,140psi | +51% | 83.7MPa |
| Modulus of elasticity | 2.68M psi | 2.87M psi | +7% | 19.8GPa |
| Modulus of rupture | 17,400psi | 20,600psi | +18% | 142MPa |
| Side hardness | 1,980lbf | 2,140lbf | +8% | 9,519N |
| Shear parallel to grain | 1,800psi | 1,960psi | +9% | 13.5MPa |
| Work to maximum load | 13in-lbf/in³ | 14.8in-lbf/in³ | +14% | 102kJ/m³ |
Wood Handbook Table 5-5b, Table 4-4. Data & method · Guides