Dipteryx odorata
Tonka
Also known as: Cumaru, Shihuahuaco
Timber GrainAbout this Timber
General Description
Tonka heartwood when cut is reddish-brown or purplish-brown with lighter streaks, and on exposure gradually becomes a uniform light brown. Lustre is low to medium, texture is fine and grain interlocked with a waxy or oily feel. Similar to spotted gum in appearance.
Working Properties
How This Timber Works
Wood is difficult to work because of its density and hardness. Hard to saw and bore, but clean edges and holes can be obtained. Planes and finishes to a smooth surface. Glues adequately.
Mechanical Properties
Timber is extremely hard and heavy, very strong and tough. Shock resistance is high.
Technical Data
Technical Specifications
*Air Dry Density (kg/m³) is an average indication only and actual values may vary. Refer to strength, shrinkage and durability classification tables for full details.
Reference Tables
Timber Classification Tables
Standard NZ classification tables for strength groupings, shrinkage and durability. This species is highlighted in each table.
| Strength Group | Modulus of Rupture | Modulus of Elasticity | Max Crushing Strength |
|---|---|---|---|
| S1 | 103 | 16300 | 52 |
| S2 | 76 | 14200 | 43 |
| S3 | 73 | 12400 | 36 |
| S4 | 62 | 10700 | 31 |
| S5 | 52 | 9100 | 26 |
| S6 | 43 | 7900 | 22 |
| S7 | 36 | 6900 | 18 |
| Strength Group | Modulus of Rupture | Modulus of Elasticity | Max Crushing Strength |
|---|---|---|---|
| SD1 | 150 | 21500 | 80 |
| SD2 | 130 | 18500 | 70 |
| SD3 | 110 | 16000 | 61 |
| SD4 | 94 | 14000 | 54 |
| SD5 | 78 | 12500 | 47 |
| SD6 | 65 | 10500 | 41 |
| SD7 | 55 | 9100 | 36 |
| SD8 | 45 | 7900 | 30 |
| Description of Shrinkage | Tangential | Radial |
|---|---|---|
| Very Low | 0 – 3.5 | 0 – 2 |
| Low | 3.5 – 5.0 | 2 – 3 |
| Medium | 5.0 – 6.5 | 3 – 4 |
| High | 6.5 – 8.0 | 4 – 5 |
| Very High | > 8.0 | > 5 |
| Grade of Durability | Fully Protected | Above Ground, Exposed | In-Ground, Exposed |
|---|---|---|---|
| Very Durable | > 50 | > 40 | > 25 |
| Durable | > 50 | 15 – 40 | 15 – 25 |
| Moderately Durable | > 50 | 7 – 15 | 5 – 15 |
| Non-Durable | > 50 | 0 – 7 | 0 – 5 |
Applications
Main Uses
Stock & Sizes
Availability
Sawn 25mm, 50mm, 75mm, 100mm, 150mm and 200mm thicknesses in varying fixed widths. Large square sections available up to 300x300mm ex stock. Larger dimensions available on request.
Quality Standard
