Merawan in Custom Epoxy Table Projects
Merawan refers to several timber species in the genus Hopea from Asia-Oceania, including Hopea odorata, Hopea sangal, Hopea mengarawan, and related botanical selections. According to the CIRAD Tropix technical sheet, mature logs range from 60 to 120 cm in diameter, making them capable of yielding wide slabs for river tables and large furniture components. The wood shows a yellow-brown to chocolate reddish-brown tone, occasionally accented with dark striping, with a fine to medium texture and grain that runs straight to slightly interlocked. Its sapwood is 5 to 7 cm thick and not clearly demarcated from the heartwood.
With a specific gravity of 0.70 at 12% moisture content, Merawan weighs approximately 43.7 lb/ft³, meaning a 2-inch-thick slab weighs roughly 7.3 lb per square foot. On the French Monnin hardness scale, it rates at 4.0. The Monnin scale measures wood resistance where higher numbers indicate harder timber (it should never be confused with or converted to Janka values). This level of hardness and solid crushing strength of 59 MPa (around 8,560 psi) provides a durable, dent-resistant surface well suited for indoor staircases, flooring, and custom tabletops.
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Hopea apiculata, Hopea dryobalanoides, Hopea griffithii, Hopea lowii, Hopea mengarawan, Hopea nervosa, Hopea odorata, Hopea papuana, Hopea pierrei, Hopea sangal, Hopea sulcata, Hopea p.p. | |
| Colour / texture / grain | Yellow brown; texture medium; grain straight or interlocked; interlocked grain slight | |
| Specific gravity (12% MC) | 0.70 | about 43.7 lb/ft³; a 2-inch-thick slab weighs about 7.3 lb per sq ft |
| Monnin hardness (12% MC) | 4.0 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 6.6 % | green to oven-dry |
| Total radial shrinkage | 3.2 % | green to oven-dry |
| Ratio St/Sr | 2.1 | closer to 1 = less cupping tendency |
| Coefficient of volumetric shrinkage | 0.47 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 20 % | |
| Thermal conductivity | 0.23 W/(m·K) | |
| Crushing strength (12% MC) | 59 MPa | about 8,560 psi |
| Static bending strength (12% MC) | 102 MPa | about 14,790 psi |
| Modulus of elasticity (12% MC) | 15,600 MPa | about 2,263,000 psi |
| Decay (fungi) resistance | Durability class 2 to 3 – durable to moderately durable | |
| Termite resistance | Class S – susceptible | |
| Dry-wood borer resistance | Class D – durable (heartw. durable but sapw. not | |
| Heartwood treatability | Class 4 – not permeable | |
| Use class from natural durability | Class 3 – not in ground contact, outside | |
| Drying | rate slow; distortion: high risk; checking: high risk; collapse: no known specific risk; casehardening: no known specific risk | |
| Suggested kiln program temperatures | 53–65 °C | about 127–149 °F |
| Machining | blunting normal; saw teeth: stellite-tipped; cutting tools: tungsten carbide | |
| Nailing and screwing | Poor | |
| CITES status | This species is not listed in the CITES Appendices (Washington Flat sawn Convention 2025). Notes. Hopea density lower than 0,85. The most dense species are marketed under the name of "GIAM". Quarter sawn |
Values from the CIRAD Tropix technical sheet (average values for mature wood, 12% moisture content where noted). US-unit conversions are calculated by BigEpoxy (1 MPa = 145.04 psi; density = specific gravity × 62.43 lb/ft³).
Pros and Cons for River Table Builders
Evaluating Merawan against an epoxy river pour requires understanding its balance of dimensional behavior and mechanical properties:
- Wide slab availability: Logs reaching 60 to 120 cm in diameter provide substantial width potential for continuous single-slab tops or live-edge river halves.
- Favorable stiffness: A modulus of elasticity of 15,600 MPa (about 2,263,000 psi) and static bending strength of 102 MPa (about 14,790 psi) provide great resistance to sag across wide spans.
- Natural fungal durability: Heartwood is rated durability class 2 to 3 (durable to moderately durable), and dry-wood borer resistance is Class D (durable in heartwood).
- Predictable machining: Normal blunting effect allows standard workshop processing using tungsten carbide cutting tools.
- Not CITES listed: Merawan is not listed in the CITES Appendices (Washington Convention 2025).
- High drying defect risks: CIRAD reports a slow drying rate paired with a high risk of checking and a high risk of distortion.
- Asymmetrical shrinkage: Total tangential shrinkage is 6.6% compared to total radial shrinkage of 3.2%, creating an St/Sr ratio of 2.1 that increases the risk of cupping next to rigid epoxy.
- Poor fastener holding: Assembling notes indicate nailing and screwing hold is poor, with wood tending to split when driving fasteners.
- Termite susceptibility: Heartwood is rated Class S (susceptible) to termites.
Build Notes: From Slab Prep to Finishing
Slab Selection
Because the 5 to 7 cm sapwood band is not clearly demarcated, examine live edges carefully. CIRAD Tropix notes that the heartwood is durable against borers while the sapwood is not, and the overall heartwood treatability is Class 4 (not permeable). For an epoxy river table, inspect slab faces for natural checking or hairline splits before cutting your river contours.
Drying Considerations
Merawan has a fiber saturation point of 20% and dries slowly. Given the high risk of checking and distortion, slabs must be brought to indoor equilibrium moisture content gradually before any resin pour. Suggested kiln schedules operate between 53 and 65 °C (about 127 to 149 °F). The coefficient of volumetric shrinkage is 0.47% per % MC; ensuring the timber is completely stabilized minimizes internal stresses that could pull the wood away from cured epoxy interfaces.
Machining
Merawan exerts a normal blunting effect on tooling. CIRAD advises stellite-tipped saw teeth and tungsten carbide cutting tools. Slight interlocked grain may require steady feed rates when planing or flattening slabs on a router sled to prevent localized tear-out.
Sealing, Fastening, and Assembly
Because heartwood is classified as Class 4 (impermeable), apply a thin seal coat of epoxy along the live edge and river trench to seal all open pores and prevent air bubbles during the deep pour. When mounting the finished tabletop to steel or wooden bases, do not rely on standard direct driving of screws. CIRAD notes that Merawan holds fasteners poorly and tends to split when nailed or screwed. Drill precise clearance holes and use threaded inserts or slotted base brackets to allow seasonal cross-grain movement across the 2.1 shrinkage ratio without cracking the wood.
Sources
Published October 31, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: Merawan wood is noted by CIRAD Tropix as being naturally resistant to acids, which explains its traditional application in cooperage and industrial container flooring. (Source: CIRAD Tropix 7 technical sheet: Merawan.)