Bulletwood
Manilkara bidentata
Bulletwood measures 3,190 lbf on the Janka scale, 147% harder than northern red oak.
- Only kaneelhart is stiffer, only kaneelhart, marishballi and macawood are stronger in bending, and only four woods are harder and four stronger for their weight.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
BulletwoodImported woods medianOther woods
Stiffness
3.45 M psi23.8 GPa2nd stiffest of 15572% above the imported woods median0.54 M psi4.06 M psiBending strength
27,300 psi188.2 MPa4th strongest of 15564% above the imported woods median4,300 psi29,900 psiJanka hardness
3,190 lbf14,190 N5th hardest of 1555th of 65 imported woods; 145% above the imported woods median240 lbf3,680 lbfDensity
0.857th heaviest of 15539% above the imported woods median0.250.96Cupping tendency
1.4923rd lowest of 1551.092.90Shrinkage across the face
9.4%radial 6.3%35th highest of 1553.5%12.7%
For its weight: strength-to-weight 32,118 psi (5th of 155).
How much it moves
It shrinks a lot, but the two directions stay close (T/R 1.49), so a board loses size more than it changes shape.
0.56 in.
off a 6-inch flatsawn board, green to oven-dry; quartersawn 0.38 in.
- Tangential
- 9.4%
- Radial
- 6.3%
- Volume
- 16.9%
- T/R ratio
- 1.49 (23rd most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- Manbarklak
9% harder · 2% heavier · shrinks 0.9 points more across the face
- Ipe
15% harder · 8% heavier · shrinks 1.4 points less across the face
- Marishballi
12% harder · 4% heavier · shrinks 2.3 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 stiffness (modulus of elasticity): 2nd highest of the 155 woods with a published value.
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Modulus of elasticity | 2.70M psi | 3.45M psi | +28% | 23.8GPa |
| Work to maximum load | 13.6in-lbf/in³ | 28.5in-lbf/in³ | +110% | 196.5kJ/m³ |
| Modulus of rupture | 17,300psi | 27,300psi | +58% | 188.2MPa |
| Side hardness | 2,230lbf | 3,190lbf | +43% | 14,190N |
| Shear parallel to grain | 1,900psi | 2,500psi | +32% | 17.2MPa |
| Compression parallel to grain | 8,690psi | 11,640psi | +34% | 80.3MPa |
Wood Handbook Table 5-5b, Table 4-4. Data & method · Guides