Visual Characteristics and Botanical Profile
Pyinkado originates from Asia-Oceania, with main distribution across Cambodia, India, Indonesia, Myanmar, Thailand, and Viet Nam. Botanically designated as Xylia xylocarpa—with Xylia dolabriformis and Xylia kerrii recognized as synonymous names—the tree produces logs typically measuring from 100 to 120 cm in diameter. According to technical documentation published in the CIRAD Tropix database, the species is not listed in the CITES Appendices (Washington Convention 2025).
For tabletop design, Pyinkado displays a distinct red-brown heartwood, which is often partly marked with dark veins and clearly visible growth rings. Live-edge builders should note that the sapwood is clearly demarcated, ranging from pale yellowish brown to reddish white, with a thickness of 2 to 5 cm. The wood presents a fine texture and grain that varies from straight to entangled, occasionally showing slight interlock. Surfaces can also exhibit occasional oily or resinous flecks, which directly impact finishing and resin adhesion prep.
Density, Hardness, and Mechanical Strength
Pyinkado is an exceptionally heavy timber. At 12% moisture content, it has an average specific gravity of 0.88, which translates to approximately 54.9 lb/ft³. In the shop, a standard 2-inch-thick slab weighs roughly 9.2 lb per square foot before resin is added. Table bases and bracing must be sized to carry significant static mass.
The wood exhibits a Monnin hardness of 6.9 at 12% moisture content. The Monnin scale is an established French testing metric where higher numerical values indicate greater resistance to indentation; it is distinct from and should never be converted to the Janka scale. Structurally, Pyinkado carries high mechanical ratings: an average crushing strength of 68 MPa (about 9,860 psi), a static bending strength of 115 MPa (about 16,680 psi), and a modulus of elasticity of 20,500 MPa (about 2,973,000 psi).
| Property | CIRAD Tropix value | What it means / US units |
|---|---|---|
| Botanical name(s) | Xylia xylocarpa, Xylia dolabriformis (synonymous), Xylia kerrii (synonymous) | |
| Colour / texture / grain | Red brown; texture fine; grain straight to entangled; 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) | 6.9 | French hardness scale; higher = harder (not a Janka value) |
| Total tangential shrinkage | 6.7 % | green to oven-dry |
| Total radial shrinkage | 3.3 % | green to oven-dry |
| Ratio St/Sr | 2.0 | closer to 1 = less cupping tendency |
| Coefficient of volumetric shrinkage | 0.48 % per % MC | volume change per 1% change in moisture content |
| Fibre saturation point | 31 % | |
| Thermal conductivity | 0.29 W/(m·K) | |
| Crushing strength (12% MC) | 68 MPa | about 9,860 psi |
| Static bending strength (12% MC) | 115 MPa | about 16,680 psi |
| Modulus of elasticity (12% MC) | 20,500 MPa | about 2,973,000 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 slow; distortion: high risk; checking: high risk; collapse: no known specific risk; casehardening: no known specific risk | |
| Suggested kiln program temperatures | 53–65 °C | about 127–149 °F |
| Machining | blunting 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).
Shrinkage Dynamics Next to an Epoxy River
When pairing solid timber with rigid epoxy casting resins, dimensional movement determines whether joints remain bonded over time. Pyinkado has a total tangential shrinkage of 6.7% and a total radial shrinkage of 3.3%, yielding an St/Sr ratio of 2.0. Its unit movement is reflected in a coefficient of volumetric shrinkage of 0.48% per 1% change in moisture content, with a fibre saturation point established at 31%.
An St/Sr ratio of 2.0 indicates that tangential movement is double the radial movement, giving flat-sawn slab faces an inherent tendency toward cupping if indoor humidity fluctuates. Because cured epoxy does not adjust its dimensions alongside wood, slabs must be thoroughly acclimated prior to casting to prevent shear stress along the river walls.
Drying Behavior and Milling Challenges
Drying Pyinkado requires strict control. CIRAD Tropix rates the drying rate as slow, accompanied by a high risk of distortion and a high risk of surface checking. There is no known specific risk of collapse or casehardening. Kiln schedules typically cycle temperatures between 53 °C and 65 °C (about 127 °F to 149 °F).
In the machine room, Pyinkado exerts a high blunting effect on tools. This strong dulling action is caused by significant internal mineral deposits and natural resin. Saws require stellite-tipped teeth, while surfacing cutters must use tungsten carbide tooling. Slicing and peeling are classified as not recommended or without interest. Additionally, fine machining and sanding dust can cause physical irritation, requiring dedicated dust extraction and personal protective equipment.
Fabrication, Fastening, and Service Applications
Due to its high specific gravity, pre-boring is mandatory for all screws and mechanical hardware. For lamination or edge-gluing, the technical sheet stresses that the high specific gravity makes it essential to perform gluing strictly in compliance with the code of practice and instructions provided by the adhesive manufacturer. Because Pyinkado occasionally holds resinous or oily flecks, joint faces should be properly cleaned before resin pours.
Naturally, Pyinkado provides extreme biological resistance: class 1 durability against wood-decay fungi, class D durability against termites, and class D against dry-wood borers (with risks restricted to the sapwood). Heartwood treatability is class 4 (not permeable). Its natural properties satisfy use class 4 (ground or freshwater immersion) and even cover use class 5 (marine environments) due to its pronounced hardness. CIRAD notes Pyinkado as acid-resistant and a direct substitute for heavy hardwoods like Greenheart, Tali, and Azobé (Ekki). Common commercial end-uses include bridges, heavy carpentry, marine and hydraulic works, industrial flooring, decking, cooperage, sleepers, and vehicle flooring.
Pre-Pour Checklist for Pyinkado Tabletops
- Acclimate the timber: Confirm that the slab has thoroughly dried through its slow drying cycle, showing no active checking or distortion, and matches the target equilibrium moisture content.
- Prepare cutting gear: Fit all shop saws with stellite-tipped blades and equip jointers and planers with sharp tungsten carbide inserts to handle severe mineral blunting.
- Implement dust protection: Set up active dust collection and wear proper masks, as Pyinkado sanding and milling dust causes irritation.
- Decontaminate river edges: Inspect the live edges or mating faces for natural resinous or oily flecks, wiping them down and preparing the surface per epoxy instructions.
- Seal the bonding faces: Apply a prime seal layer along the river boundaries to address the fine-textured, non-permeable heartwood before completing the main deep pour.
- Pre-drill all structural mounts: Drill full-depth pilot holes for every threaded insert or base screw, accommodating the dense 0.88 specific gravity timber without splitting.
Sources
Published October 30, 2026. Sources are linked in the text.
Header image: original graphic by BigEpoxy.com.
Staff note: Pyinkado carries natural resistance to acids, which explains its traditional industrial use in cooperage and chemical-resistant flooring alongside heavy marine structures. (Source: CIRAD Tropix 7 technical sheet: Pyinkado.)