Determa
Ocotea rubra
Determa measures 660 lbf on the Janka scale, 49% softer than northern red oak.
- Only four woods sit further below the density–hardness trend: a specific gravity of 0.52 would point to about 1,150 lbf.
- Douglas-fir (Interior West) and primavera have exactly the same Janka figure.
- On the Janka scale its nearest neighbours are Port-Orford-cedar at 630 lbf and mountain hemlock at 680 lbf.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
DetermaImported woods medianOther woods
Cupping tendency
2.0540th highest of 1551.092.90Bending strength
10,500 psi72.4 MPa43rd weakest of 15537% below the imported woods median4,300 psi29,900 psiJanka hardness
660 lbf2,936 N49th softest of 15553rd of 65 imported woods; 49% below the imported woods median240 lbf3,680 lbfStiffness
1.82 M psi12.6 GPa55th stiffest of 1550.54 M psi4.06 M psiDensity
0.5269th heaviest of 1550.250.96Shrinkage across the face
7.6%radial 3.7%70th lowest of 1553.5%12.7%
For its weight: strength-to-weight 20,192 psi (151st of 155).
How much it moves
Both its face shrinkage (7.6%) and its T/R ratio (2.05) sit in the middle half of the list.
0.46 in.
off a 6-inch flatsawn board, green to oven-dry; quartersawn 0.22 in.
- Tangential
- 7.6%
- Radial
- 3.7%
- Volume
- 10.4%
- T/R ratio
- 2.05 (115th most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- Dark red meranti
18% harder · 12% lighter · shrinks 0.3 points more across the face
- Yellow meranti
17% harder · 12% lighter · shrinks 0.4 points more across the face
- Bigleaf maple
29% harder · 15% lighter · shrinks 0.5 points less across the face
Woods of similar hardness
The eight nearest on the Janka scale, lbf.
Laboratory values
Its most unusual laboratory figure is work to maximum load: 10th lowest of the 142 woods with a published value.
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Work to maximum load | 4.80in-lbf/in³ | 6.40in-lbf/in³ | +33% | 44.1kJ/m³ |
| Shear parallel to grain | 860psi | 980psi | +14% | 6.80MPa |
| Modulus of rupture | 7,800psi | 10,500psi | +35% | 72.4MPa |
| Compression parallel to grain | 3,760psi | 5,800psi | +54% | 40MPa |
| Side hardness | 520lbf | 660lbf | +27% | 2,936N |
| Modulus of elasticity | 1.46M psi | 1.82M psi | +25% | 12.6GPa |
Wood Handbook Table 5-5b, Table 4-4. Data & method · Guides