Working with Angelim Vermelho in Epoxy River Tables
Angelim vermelho (Dinizia excelsa) is a massive timber from Latin America known for extreme density, structural stiffness, and biological durability. Data from the CIRAD Tropix technical sheet shows that this species is heavily utilized in demanding industrial projects such as bridge building, shipbuilding planking, heavy carpentry, vehicle flooring, and indoor staircases. When brought into a custom wood and epoxy table build, its mechanical performance is undeniable, but its sheer weight, drying behavior, and high density demand specific shop precautions.
Appearance, Figure, and Shop Characteristics
The heartwood of Angelim vermelho presents a rich red brown color, separated from a clearly demarcated sapwood that measures between 5 and 10 cm in thickness. The wood exhibits a medium texture with grain that is straight or slightly interlocked. In the raw lumber stage, logs typically range from 65 to 120 cm in diameter, though hollow centers are noted as very common. A critical practical factor during preparation is that Angelim vermelho carries an unpleasant odour when green or rewetted, which dissipates as the wood dries.
Weight, Hardness, and Mechanical Strength
Angelim vermelho is exceptionally dense, carrying an average specific gravity of 1.07 at 12% moisture content (about 66.8 lb/ft³). Because of this density, the timber does not float. For table makers, a 2-inch-thick slab weighs approximately 11.1 lb per square foot before resin is added. Table bases and hardware must be engineered to hold significant mass.
The wood registers a Monnin hardness of 17.1. The Monnin scale is an established French testing metric where higher values reflect greater surface hardness and resistance to indentation; it is fundamentally distinct from tests like Janka and cannot be directly converted. Backing this surface toughness are substantial structural values: a crushing strength of 89 MPa (about 12,910 psi), a static bending strength of 160 MPa (about 23,210 psi), and a modulus of elasticity of 26,280 MPa (about 3,812,000 psi).
Dimensional Shrinkage and Epoxy River Interaction
When pairing solid wood slabs with rigid epoxy resin in a river pour, managing wood movement is essential to protect the bondline. Angelim vermelho has a total tangential shrinkage of 8.5% and a total radial shrinkage of 5.1% from green to oven-dry, resulting in a tangential-to-radial shrinkage ratio of 1.7. Its coefficient of volumetric shrinkage is 0.68% per 1% change in moisture content, with a fiber saturation point recorded at 23%.
Because the ratio sits at 1.7, cupping risks are moderate rather than extreme, but the high volumetric shrinkage coefficient means any seasonal shifts in ambient moisture will exert heavy stresses along the resin interface. Thorough sealing and careful moisture equalization prior to encapsulation are necessary to avoid shear stresses against cured polymer.
Drying Risks, Tool Blunting, and Fabrication
According to CIRAD Tropix research, Angelim vermelho exhibits a normal to slow drying rate. The technical sheet lists only a slight risk of checking and a slight risk of distortion, with no known specific risk of casehardening. However, there is an explicit risk of collapse during drying. CIRAD recommends air drying prior to kiln drying, followed by slow, cautious kiln cycles with suggested schedule temperatures running between 45 °C and 65 °C (about 113 °F to 149 °F).
Machining this hardwood requires dedicated tooling. The blunting effect on cutters is fairly high and requires power; the CIRAD data sheet recommends stellite-tipped saw teeth and tungsten carbide cutting tools. For joining and table-base attachment, pre-boring is strictly necessary before driving screws or nails. Because of the very high specific gravity, CIRAD notes that gluing must be especially performed in compliance with standard codes of practice to guarantee sound structural adhesion.
Durability and Environmental Status
The heartwood of Angelim vermelho achieves Durability Class 1 (very durable) against wood-decay fungi, Class D (durable) against dry-wood borers, and Class D (durable) against termites. Its heartwood treatability is Class 4 (not permeable). It naturally covers Use Class 4 (ground or freshwater contact) and even Use Class 5 under European standard NF EN 350 for marine exposure. Angelim vermelho is not listed in the CITES Appendices (Washington Convention 2025).
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Dinizia excelsa | |
| Colour / texture / grain | Red brown; texture medium; grain straight or interlocked; interlocked grain slight | |
| Specific gravity (12% MC) | 1.07 | about 66.8 lb/ft³; a 2-inch-thick slab weighs about 11.1 lb per sq ft |
| Monnin hardness (12% MC) | 17.1 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 8.5 % | green to oven-dry |
| Total radial shrinkage | 5.1 % | green to oven-dry |
| Ratio St/Sr | 1.7 | closer to 1 = less cupping tendency |
| Coefficient of volumetric shrinkage | 0.68 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 23 % | |
| Thermal conductivity | 0.34 W/(m·K) | |
| Crushing strength (12% MC) | 89 MPa | about 12,910 psi |
| Static bending strength (12% MC) | 160 MPa | about 23,210 psi |
| Modulus of elasticity (12% MC) | 26,280 MPa | about 3,812,000 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 4 – not 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: yes; 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).
Practical Pre-Pour Checklist for Angelim Vermelho Slabs
- Check for internal drying collapse: Examine the board faces and end grain carefully for internal cell collapse or washboarding from prior kiln cycles.
- Confirm dry moisture equilibrium: Verify that the timber is fully dried down through the core, keeping in mind its slow drying rate and 23% fiber saturation point.
- Inspect for sapwood boundaries: Ensure all sapwood (typically 5 to 10 cm thick) is either removed or sound, as borer risks are limited strictly to the sapwood.
- Surface prep for dense gluing: Dress the gluing edges freshly with sharp tungsten carbide tools and clean all bond surfaces in strict compliance with dense-hardwood gluing practices.
- Pre-bore all mechanical fasteners: Drill clearance and pilot holes for any threaded inserts, table legs, or mold-securing screws to avoid snapping hardware in 17.1 Monnin timber.
- Verify base support capacity: Calculate total tabletop mass based on the wood’s 1.07 specific gravity (approximately 11.1 lb per square foot for a 2-inch slab) plus resin volume.
Sources
Published October 30, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: CIRAD Tropix records a thermal conductivity value of 0.34 W/(m·K) for Angelim vermelho, which reflects how heat moves through this dense species during both kiln heating phases and the exothermic reaction of deep-pour resin castings. (Source: CIRAD Tropix 7 technical sheet: Angelim vermelho.)