Tropical wood · Southeast Asia and Oceania
Resak wood
Resak (Cotylelobium spp., family Dipterocarpaceae) is a tropical timber from Southeast Asia and Oceania. Dry, its Janka hardness is 1,550 lbf (6,895 N), and air-dry it weighs about 40–65 lb/ft³ (641–1,041 kg/m³). The figures are from the USDA Forest Products Laboratory's Tropical Timbers of the World, pp. 597–598.
Other names, by country: Láu táu (Cambodia), Chan thip (Thailand), Narig (Philippines), Mascal wood (India), Taungsagaing (Burma).
Key numbers
- Janka hardness, dry
- 1,550 lbf (6,895 N)
- Green: 1,120 lbf (4,982 N)
- As printed: “Janka side hardness 1,120 lb for green material and 1,550 lb for dry.”
- Air-dry density
- 40–65 lb/ft³ (641–1,041 kg/m³)
- Basic specific gravity
- 0.52–0.85 oven-dry weight, green volume
- As printed: “Basic specific gravity (ovendry weight/green volume) varies considerably with species from 0.52 to 0.85; air-dry density 40 to 65 pcf.”
- Shrinkage, green to oven-dry
- 9.3% tangential
- Radial 4.0%
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 | 10,900 psi (75 MPa) | 1.9 million psi (13.1 GPa) | 5,560 psi (38 MPa) |
| 12% MC | 19,600 psi (135 MPa) | 2.54 million psi (17.5 GPa) | 9,000 psi (62 MPa) |
| 12% MC | 17,000 psi (117 MPa) | — | 7,500 psi (52 MPa) |
A dash means the sheet prints no value; none is filled in.
What the data sheet says
- Color, grain and texture
- Heartwood yellowish when fresh, turning light to deep red-brown on exposure; sapwood lighter than heartwood, generally not sharply defined. Texture rather fine and even; grain straight or shallowly interlocked; not lustrous; without distinctive taste or odor when dry. Silica present in Cotylelobium.
- Working properties
- Reported to be difficult to saw because of clogging due to gummy resins; otherwise machines well to a smooth finish; turns well. Due to silica in Cotylelobium there is dulling of cutters.
- Durability
- Heartwood, particularly that of the denser species, rated as durable to very durable; termite resistance is similarly rated.
- Uses
- Turnery, heavy construction, mining timbers, railroad crossties, boat construction, also suggested for flooring, interior joinery, and cabinetwork.
- Where it grows
- Widespread in Southeast Asia from India and Ceylon to New Guinea.
Quoted from Tropical Timbers of the World, pp. 597–598, a USDA Forest Products Laboratory work in the public domain.
Work it out for your project
- Rank woods for cabinets and trim with the species picker
Weigh resak against other woods on hardness, weight, movement and color, every figure from the Wood Handbook.