Working with Angueuk in Epoxy River Tables
Angueuk (Ongokea gore) is a dense hardwood from Africa. Evaluated extensively in the CIRAD Tropix technical sheet, this timber offers distinct visual qualities and formidable mechanical strength. For makers designing epoxy river tables and custom wood-and-resin furniture, Angueuk presents both standout aesthetic advantages and specific stability challenges that demand disciplined shop preparation.
Appearance and Visual Characteristics
Angueuk displays a pale yellow, slightly brownish heartwood that darkens when exposed to light. The wood features a medium texture with grain that is straight or interlocked, showing slight interlocking. When quartersawn, the interlocked grain produces a distinct ribbon-like aspect, and the grain can sometimes be wavy. Flat-sawn surfaces display subtle, clean figuring. The sapwood is not clearly demarcated from the heartwood, typically spanning from 7 to 10 cm in thickness.
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Ongokea gore | |
| Colour / texture / grain | Yellow; texture medium; grain straight or interlocked; interlocked grain slight | |
| Specific gravity (12% MC) | 0.88 | about 54.9 lb/ft³; a 2-inch-thick slab weighs about 9.2 lb per sq ft |
| Monnin hardness (12% MC) | 5.8 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 11.8 % | green to oven-dry |
| Total radial shrinkage | 4.5 % | green to oven-dry |
| Ratio St/Sr | 2.6 | closer to 1 = less cupping tendency |
| Coefficient of volumetric shrinkage | 0.57 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 30 % | |
| Thermal conductivity | 0.29 W/(m·K) | |
| Crushing strength (12% MC) | 67 MPa | about 9,720 psi |
| Static bending strength (12% MC) | 107 MPa | about 15,520 psi |
| Modulus of elasticity (12% MC) | 15,610 MPa | about 2,264,000 psi |
| Decay (fungi) resistance | Durability class 2 – durable | |
| Termite resistance | Class D – durable | |
| Dry-wood borer resistance | Class D – durable (heartw. durable but sapw. not | |
| Heartwood treatability | Class 3 – poorly permeable | |
| Use class from natural durability | Class 3 – not in ground contact, outside | |
| Drying | rate slow; distortion: high risk; checking: slight 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: ordinary or alloy steel; cutting tools: ordinary | |
| 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).
Mechanical Properties and Hardness
Angueuk is a heavy, substantial hardwood with an average specific gravity of 0.88 at 12% moisture content. That places its density at about 54.9 lb/ft³, meaning a 2-inch-thick slab weighs about 9.2 lb per sq ft. Its hardness varies from fairly hard to hard, registering an average Monnin hardness of 5.8. On the French Monnin scale, higher numbers indicate greater resistance to indentation (unlike the imperial Janka scale, Monnin values are derived from a cylindrical penetration test and should never be converted directly to Janka). Its high mechanical ratings also include a crushing strength of 67 MPa (about 9,720 psi), static bending strength of 107 MPa (about 15,520 psi), and a modulus of elasticity of 15,610 MPa (about 2,264,000 psi).
Pros of Angueuk for Epoxy Tabletops
- Attractive figure: Quartersawn stock yields an appealing ribbon-like aspect, often enhanced by wavy grain.
- High strength and hardness: A Monnin rating of 5.8 and high compressive strength create an exceptionally durable, wear-resistant tabletop surface.
- Natural resistance: Heartwood achieves Durability class 2 against decay fungi, Class D against termites, and Class D against dry-wood borers.
- Standard tooling compatibility: Despite high density, the blunting effect on cutters is normal, allowing the use of ordinary or alloy steel saw teeth and ordinary cutting tools.
- Unrestricted trade status: Angueuk is not listed in the CITES Appendices (Washington Convention 2025).
Cons of Angueuk for Epoxy Tabletops
- High movement and cupping risk: Total tangential shrinkage is 11.8%, while radial shrinkage is 4.5%, resulting in a high shrinkage ratio (St/Sr) of 2.6.
- Significant distortion risk during drying: CIRAD reports a high risk of distortion and a slow drying rate, requiring quartersawn conversion to stay flat.
- Demanding gluing requirements: Because of its 0.88 specific gravity, gluing must strictly comply with industry codes of practice to prevent joint separation.
- Poor heartwood permeability: Rated Class 3 (poorly permeable), which limits deep chemical penetration.
- Weight: Substantial density (about 54.9 lb/ft³) demands robust leg hardware and base designs.
- Fastener splitting: Tends to split when nailed, making pre-boring necessary for any mechanical fasteners.
Build Notes for Slab Selection and Table Construction
Slab Selection
Logs typically range from 80 to 100 cm in diameter, offering solid widths for slabs and river layouts. However, because the sapwood measures from 7 to 10 cm and is not clearly demarcated, inspect live edges closely. Quartersawn or rift-sawn boards are strongly preferred over flat-sawn planks to minimize transverse cupping against cured epoxy channels.
Drying and Moisture Management
Angueuk dries at a slow rate and carries a high risk of distortion, though checking carries only a slight risk and there is no known specific risk of collapse or casehardening. The fiber saturation point sits at 30%, with a volumetric shrinkage coefficient of 0.57% per percent change in moisture content. The CIRAD schedule advises drying quartersawn material and running kiln temperatures between 53 and 65 °C (about 127 to 149 °F). Slabs must be thoroughly acclimated to shop equilibrium before pouring epoxy to prevent uneven stresses along the river bondline.
Machining and Fastening
While Angueuk machines with ordinary tooling, CIRAD notes that cutting and processing this species requires power. Feed rates should remain steady. Pre-boring is strictly necessary for all table-base mounting screws to prevent splits near threaded fasteners.
Sealing and Epoxy Pouring
Angueuk’s Class 3 poor permeability means seal coats must be applied carefully to saturate open surface pores. Because dense species experience shear stress along the wood-resin interface as ambient humidity fluctuates, edge joints must be cleanly milled and wiped clean before pouring deep epoxy rivers.
Sources
Published October 31, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: Beyond interior joinery and sliced veneer, CIRAD records Angueuk in heavy-duty commercial roles like industrial flooring and container flooring, highlighting its severe-wear resistance. (Source: CIRAD Tropix 7 technical sheet: Angueuk.)