Wacapou for Wood and Epoxy Tabletops
Wacapou (Vouacapoua americana), also traded under names like Partridgewood and Tatbu, is a dense Latin American hardwood originating from countries such as Brazil, French Guiana, Guyana, and Suriname. Documented by the wood research specialists at CIRAD Tropix, Wacapou is prized for its decorative character and physical resilience, making it a distinctive candidate for custom furniture, high-class cabinetwork, and epoxy river tabletops.
Visually, Wacapou features a dark brown heartwood marked by thin light brown lines that create an attractive aesthetic. Its sapwood is clearly demarcated and measures from 2 to 3 cm thick. The wood has a medium texture with straight grain, and interlocked grain is completely absent. Log diameters range from 40 to 100 cm, giving builders the opportunity to source boards or modest single-slab widths for table layouts.
From a mechanical perspective, Wacapou is very dense and firm. At 12% moisture content, it has an average specific gravity of 0.92, translating to a density of about 57.4 lb/ft³. A 2-inch-thick slab weighs about 9.6 lb per sq ft, requiring sturdy bases and heavy-duty leg hardware. On the French Monnin hardness scale—where higher numbers indicate harder wood, not to be confused with or converted to Janka values—Wacapou scores 6.9, showing exceptional resistance to indentation.
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Vouacapoua americana | |
| Other trade names | Partridgewood, Tatbu | |
| Colour / texture / grain | Dark brown; texture medium; grain straight; interlocked grain absent | |
| Specific gravity (12% MC) | 0.92 | about 57.4 lb/ft³; a 2-inch-thick slab weighs about 9.6 lb per sq ft |
| Monnin hardness (12% MC) | 6.9 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 6.5 % | green to oven-dry |
| Total radial shrinkage | 4.2 % | green to oven-dry |
| Ratio St/Sr | 1.5 | closer to 1 = less cupping tendency |
| Coefficient of volumetric shrinkage | 0.65 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 22 % | |
| Thermal conductivity | 0.30 W/(m·K) | |
| Crushing strength (12% MC) | 82 MPa | about 11,890 psi |
| Static bending strength (12% MC) | 148 MPa | about 21,470 psi |
| Modulus of elasticity (12% MC) | 19,780 MPa | about 2,869,000 psi |
| Decay (fungi) resistance | Durability class 1 – very durable | |
| Termite resistance | Class D – durable | |
| Dry-wood borer resistance | Class D – durable (sapwood demarcated, risk limited | |
| Heartwood treatability | Class 3 – poorly permeable | |
| Use class from natural durability | Class 4 – in ground or fresh water contact | |
| Drying | rate normal to slow; distortion: slight risk; checking: slight risk; collapse: no known specific risk; casehardening: no known specific risk | |
| Suggested kiln program temperatures | 45–65 °C | about 113–149 °F |
| Machining | blunting fairly high; saw teeth: stellite-tipped; cutting tools: tungsten carbide | |
| Nailing and screwing | Good but pre-boring necessary | |
| CITES status | This species is not listed in the CITES Appendices (Washington Convention 2025). |
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).
Dimensional Stability Beside an Epoxy River
When embedding timber in epoxy resin, dimensional movement is a fundamental factor. Wacapou exhibits a total tangential shrinkage of 6.5% and a total radial shrinkage of 4.2% from green to oven-dry conditions. Its ratio of tangential to radial shrinkage (St/Sr) is 1.5, which indicates a low to moderate tendency toward cupping or warping across flatsawn surfaces.
The wood has a coefficient of volumetric shrinkage of 0.65% per 1% change in moisture content, alongside a fibre saturation point of 22%. Because epoxy does not shrink or expand with seasonal humidity, the timber must be thoroughly dried and acclimated to interior equilibrium moisture content before casting. Any dimensional movement against an unyielding epoxy bond line can otherwise induce stress.
Drying, Machining, and Assembly Guidelines
The drying rate for Wacapou is normal to slow. According to CIRAD Tropix, initial surface drying prior to kiln drying is recommended. Slabs present a slight risk of distortion and a slight risk of checking, while risks of casehardening and collapse show no known specific issues. Suggested kiln schedules operate between 45 and 65 °C (about 113 to 149 °F). Slabs should also be assessed for internal stresses noted in the technical data.
Machining Wacapou requires dedicated tooling. The wood exerts a fairly high blunting effect on cutters. CIRAD Tropix specifies the use of stellite-tipped saw teeth and tungsten carbide cutting edges, noting that processing requires significant power. For joinery and mounting, nailing and screwing properties are good, but pre-boring is strictly necessary to prevent splitting. Furthermore, because of the wood’s high specific gravity, adhesive bonding must be executed carefully in compliance with professional codes of practice. When pouring resin, wood surfaces should be properly prepared, clean, and sealed according to the epoxy manufacturer’s directions.
Frequently Asked Questions
What does Wacapou look like in a finished tabletop?
Wacapou displays a dark brown heartwood accentuated by fine, light brown lines. The grain is straight, with no interlocked grain, providing a clean, linear pattern that contrasts vividly against tinted or clear resin pours.
How wide are Wacapou logs for slab projects?
Logs generally range from 40 to 100 cm in diameter. With a sapwood band of 2 to 3 cm, woodworkers can acquire boards and mid-sized slabs suitable for dining tables, conference tops, or two-piece bookmatched river tables.
What is Monnin hardness, and how hard is Wacapou?
Monnin hardness is a standardized French timber hardness test where higher numbers reflect greater surface hardness. Wacapou measures 6.9 on this scale. It must not be converted to a Janka figure, as the testing parameters differ, but the rating confirms a very rigid, wear-resistant surface.
Is Wacapou stable when bonded with epoxy?
With an St/Sr ratio of 1.5, Wacapou demonstrates uniform shrinkage behavior between radial and tangential planes. However, its total tangential shrinkage of 6.5% and volumetric coefficient of 0.65% per 1% moisture change mean that slabs must be completely dry and sealed to prevent shear stress along the epoxy interface.
Does Wacapou require special tools or pre-drilling?
Yes. Due to its density and a fairly high blunting effect, stellite-tipped saw blades and tungsten carbide cutters are recommended. Pre-boring is required for all screws and fasteners to prevent splitting near edges and joints.
What is the CITES and durability status of Wacapou?
Wacapou is not listed in the CITES Appendices (Washington Convention 2025). In terms of durability, the heartwood is Durability Class 1 (very durable against fungi) and Class D (durable against termites and dry-wood borers), making it naturally resilient against decay organisms.
Sources
Published October 31, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: CIRAD Tropix notes that Wacapou contains natural internal stresses and repulsive extractives that grant it high resistance against biological attack, but these same dense extractives mean woodworkers should ensure surfaces are freshly prepped before edge-gluing or applying resin seal coats. (Source: CIRAD Tropix 7 technical sheet: Wacapou.)