African Canarium in Wood and Epoxy Table Builds
African canarium (Canarium schweinfurthii) is an African hardwood occasionally encountered by makers seeking distinct character for custom furniture. To understand how this species performs when paired with liquid polymer casting resins, woodworkers can look to the technical data compiled by the forestry researchers at CIRAD Tropix. From movement properties to tool resistance, the timber offers a unique profile that requires thoughtful preparation in the shop.
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Canarium schweinfurthii | |
| Colour / texture / grain | Pinkish brown; texture coarse; grain interlocked; interlocked grain marked | |
| Specific gravity (12% MC) | 0.49 | about 30.6 lb/ft³; a 2-inch-thick slab weighs about 5.1 lb per sq ft |
| Monnin hardness (12% MC) | 1.3 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 9.9 % | green to oven-dry |
| Total radial shrinkage | 5.9 % | green to oven-dry |
| Ratio St/Sr | 1.7 | closer to 1 = less cupping tendency |
| Coefficient of volumetric shrinkage | 0.42 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 40 % | |
| Thermal conductivity | 0.17 W/(m·K) | |
| Crushing strength (12% MC) | 36 MPa | about 5,220 psi |
| Static bending strength (12% MC) | 59 MPa | about 8,560 psi |
| Modulus of elasticity (12% MC) | 10,490 MPa | about 1,521,000 psi |
| Decay (fungi) resistance | Durability class 5 – not durable | |
| Termite resistance | Class S – susceptible | |
| Dry-wood borer resistance | Class S – susceptible (risk in all the wood) | |
| Heartwood treatability | Class 4 – not permeable | |
| Use class from natural durability | Class 1 – inside (no dampness) | |
| Drying | rate slow; distortion: high risk; checking: high risk; collapse: yes; casehardening: no known specific risk | |
| Suggested kiln program temperatures | 53–62 °C | about 127–144 °F |
| Machining | blunting fairly high; saw teeth: stellite-tipped; cutting tools: tungsten carbide | |
| Nailing and screwing | Poor | |
| 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 African canarium look like in custom tabletops?
African canarium presents a pinkish brown heartwood, sometimes described as light brown slightly pinkish. The wood features a coarse texture with marked interlocked grain, which provides visual texture across wide surfaces. Because the sapwood is not demarcated from the heartwood, boards exhibit a continuous coloration across their width rather than high-contrast sapwood edges. When preparing live-edge or dimensional slabs for an epoxy pour, makers should inspect the boards carefully, as CIRAD notes report the possible presence of wind shakes within the timber structure.
How wide are African canarium slabs?
Logs harvested from Canarium schweinfurthii typically range from 80 to 120 cm in diameter. With sapwood thickness running from 5 to 10 cm, sawyers can produce wide single-slab bookmatches or substantial planks suitable for large river table layouts. In terms of trade regulation, African canarium is not listed in the CITES Appendices (Washington Convention 2025), allowing it to enter standard commercial lumber channels where available.
What are the density and hardness ratings of African canarium?
At 12% moisture content, African canarium has a specific gravity of 0.49, equating to an average density of about 30.6 lb/ft³. For tabletop builders, this means a 2-inch-thick slab weighs roughly 5.1 lb per sq ft, making it significantly lighter than dense tropical hardwoods and easier to handle during assembly. On the French Monnin hardness scale, it rates at 1.3. The Monnin test uses a calibrated cylinder indentation where higher numbers represent harder wood (it is not a Janka rating and should not be converted). A rating of 1.3 indicates a relatively soft surface that may dent under heavy impact if not protected by a suitable finish.
How does shrinkage affect African canarium in an epoxy river table?
Dimensional movement is a critical factor when bonding solid wood to a rigid epoxy casting. The CIRAD Tropix technical sheet reports a total tangential shrinkage of 9.9 % and a total radial shrinkage of 5.9 %, yielding an St/Sr ratio of 1.7. The volumetric shrinkage coefficient is 0.42 % per % moisture content, with a high fibre saturation point of 40 %. Because the wood expands and contracts moderately across moisture fluctuations, slabs must be thoroughly acclimated before casting. If raw boards gain or lose moisture beside an immovable epoxy river, cross-grain stress can lead to edge separation or panel cupping.
What are the drying risks and defects to watch for?
African canarium requires strict patience during moisture removal. The CIRAD testing indicates a slow drying rate accompanied by a high risk of distortion, a high risk of checking, and a susceptibility to collapse. Standard kiln schedules for this timber range between 53 and 62 °C (about 127 and 144 °F) with high initial humidity to prevent severe defects. Slabs must be dried slowly and carefully. In addition, the species is prone to blue stain, meaning logs and fresh lumber require swift, controlled drying to prevent sapwood discoloration before fabrication begins.
How does African canarium machine and hold fasteners?
Working African canarium poses moderate demands on shop equipment. Although relatively light, its blunting effect on cutting edges is rated as fairly high. To prevent burning and premature wear, tooling recommendations include stellite-tipped saw teeth and tungsten carbide cutters. The marked interlocked grain can cause surface tearout during planing if cuts are too aggressive. For table joinery and base attachments, builders should note that mechanical holding power is rated as poor for nailing and screwing. Threaded inserts or reinforced mechanical joinery are advisable when securing heavy steel bases to the underside of the top.
What are the durability ratings and recommended end-uses?
African canarium is not suited for outdoor service. According to CIRAD, the heartwood sits in Durability class 5 (not durable against wood-decay fungi) and is rated Class S (susceptible) to dry-wood borers and termites. Heartwood treatability is Class 4 (not permeable). The natural durability corresponds strictly to Use Class 1 (interior use with no dampness), and any temporary or permanent humidification is not recommended. Documented commercial end-uses include interior joinery, interior panelling, sliced veneer, current furniture or furniture components, blockboard, and core or face veneer for plywood.
Sources
Published October 31, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: In addition to lumber uses, CIRAD Tropix notes that African canarium logs float in water and the species can serve as an industrial substitute for Okoumé (Aucoumea klaineana) in plywood production. (Source: CIRAD Tropix 7 technical sheet: African canarium.)