Working with Dina in Custom Wood and Epoxy Tabletops
Dina, botanically classified as Bobgunnia fistuloides (synonymous with Swartzia fistuloides) and also traded under the name Pao rosa, is a dense African hardwood. Sourced from producing countries such as Cameroon, Gabon, Côte d’Ivoire, and the Democratic Republic of the Congo, it is prized for high-class furniture and turnery. When pairing this timber with deep-pour epoxy resin systems, builders must understand its density, moisture movement, and shop characteristics based on published research from the CIRAD Tropix technical sheet.
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Bobgunnia fistuloides, Swartzia fistuloides (synonymous) | |
| Other trade names | Pao rosa | |
| Colour / texture / grain | Light red; texture fine; grain interlocked; interlocked grain slight | |
| Specific gravity (12% MC) | 1.02 | about 63.7 lb/ft³; a 2-inch-thick slab weighs about 10.6 lb per sq ft |
| Monnin hardness (12% MC) | 9.1 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 6.2 % | 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 | 0.66 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 19 % | |
| Thermal conductivity | 0.33 W/(m·K) | |
| Crushing strength (12% MC) | 90 MPa | about 13,050 psi |
| Static bending strength (12% MC) | 149 MPa | about 21,610 psi |
| Modulus of elasticity (12% MC) | 21,290 MPa | about 3,088,000 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 slow; distortion: slight risk; checking: high risk; collapse: no known specific risk; casehardening: no known specific risk | |
| Suggested kiln program temperatures | 45–65 °C | about 113–149 °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).
What does Dina look like, and what slab widths are available?
Dina heartwood presents a light red appearance, with the wood ranging from pinkish white to light red accented by red-brown veins. The sapwood is clearly demarcated from the heartwood, with a measured thickness of 1 to 2 cm. The wood exhibits a fine texture and interlocked grain, with the interlocked grain rated as slight. Log diameters are reported from 50 to 80 cm, providing modest slab widths suitable for bookmatched river table layouts, multi-board dining surfaces, or accent tables.
How heavy and hard is Dina wood?
Dina is an exceptionally heavy hardwood with an average specific gravity of 1.02 at 12% moisture content. According to BigEpoxy calculations, this equates to roughly 63.7 lb/ft³, meaning a 2-inch-thick slab weighs approximately 10.6 lb per square foot. Mechanical testing shows high resistance: crushing strength averages 90 MPa (about 13,050 psi), static bending strength reaches 149 MPa (about 21,610 psi), and the modulus of elasticity is 21,290 MPa (about 3,088,000 psi).
Hardness is measured using the Monnin scale, a French test where higher values indicate harder material (it should not be converted to Janka values). Dina registers a Monnin hardness of 9.1 at 12% moisture content. This places it well into the very hard category, providing extreme dent resistance for tabletop applications.
How does Dina behave during drying?
Dina has a slow drying rate. The CIRAD Tropix data notes a slight risk of distortion, but a high risk of checking, with no known specific risk of collapse or casehardening. Builders should watch for end checking and the extension of existing cracks during moisture equalization. Kiln drying schedules suggest starting at 45 °C (about 113 °F) and ending at 65 °C (about 149 °F) to safely remove moisture without aggravating checks.
How stable is Dina next to an epoxy river?
Because epoxy does not expand or contract with ambient humidity, pairing it with wood requires tracking dimensional shrinkage. Dina demonstrates moderate dimensional movement:
- Total tangential shrinkage: 6.2 %
- Total radial shrinkage: 4.2 %
- Shrinkage ratio (St/Sr): 1.5
- Coefficient of volumetric shrinkage: 0.66 % per % change in moisture content
- Fibre saturation point: 19 %
A tangential-to-radial shrinkage ratio of 1.5 indicates a low to moderate tendency to cup or distort. However, with a volumetric coefficient of 0.66 %, every percentage change in moisture content creates significant internal stress. Slabs must be thoroughly dried to equilibrium before casting epoxy, and table assemblies should be sealed on all faces to prevent differential movement.
How does Dina handle machining, drilling, and tooling?
Tool blunting is rated as normal, and ordinary cutting tools or ordinary or alloy steel saw teeth can be used. However, because of the wood’s density, working Dina requires power. CIRAD notes that sawblades can vibrate and overheat, and there is a tendency to burn the wood during boring. Machinists may encounter slight woolliness on occasion. Additionally, Dina sawdust is noted as sometimes irritant, making effective dust collection essential during surface surfacing and sanding.
What should builders know about gluing and fastening Dina?
Fastening performance for nailing and screwing is good, but pre-boring is necessary due to the extreme hardness and splitting risk. CIRAD Tropix warns that because of its very high specific gravity, gluing must be especially performed in compliance with the code of practice. When preparing Dina edges for resin bonds, ensure mating surfaces are freshly machined, flat, clean, and free from loose dust, and follow your resin manufacturer’s technical data sheet for heavy, dense tropical hardwoods.
How naturally durable is Dina, and what is its CITES status?
The heartwood of Dina offers outstanding biological resistance. It is classified as Durability class 1 (very durable) against wood-decay fungi, Class D (durable) against termites, and Class D (durable) against dry-wood borers, with heartwood treatability rated Class 3 (poorly permeable). Its natural durability corresponds to Use Class 4, permitting ground or freshwater contact. Listed commercial end-uses include cabinetwork (high-class furniture), cooperage, percussion instruments, tool handles, sculpture, turned goods, and sliced veneer. In addition, this species is not listed in the CITES Appendices (Washington Convention 2025).
Sources
Published October 31, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: CIRAD Tropix documents that Dina is resistant to one or several acids, reflecting a chemical resilience that pairs well with heavy-use furniture or specialty casework. (Source: CIRAD Tropix 7 technical sheet: Dina.)