Timber Species American Black Walnut

Juglans nigra

American Black Walnut

Also known as: Black Walnut, Canaletto, Black Hickory Nut

Region of Origin: United States
FurnitureCabinet MakingInterior JoineryBoatbuildingMusical InstrumentsRifle Butts & Gunstocks
Density
609 kg/m³
Durability
Very Durable
Janka
4.5 kN
Strength Group
SD4
American Black Walnut timber grainTimber Grain

About this Timber

General Description

American Black Walnut heartwood is a rich dark chocolate brown to purplish-black, mostly straight grained but with wavy or curly grain occasionally present. The texture is mildly coarse. Walnut is usually supplied steamed, to darken the pale coloured sapwood.

US forests have a long-standing tradition of sustainable forest management, bolstered by a strong legal framework for environmental conservation.

Working Properties

How This Timber Works

Works without difficulty with hand or machine tools and has moderate blunting effect. Holds nails or screws well, glues satisfactorily and polishes to a high finish.

Mechanical Properties

This is a tough, hard timber of medium density, with moderate bending and crushing strengths, and low stiffness. It has good steam bending classification.

Technical Data

Technical Specifications

Density
609kg/m³
Air dry density (avg)
Durability Class
Very Durable
Strength Group
SD4
Structural classification
Janka Hardness
4.5kN
Surface hardness rating
MOR — Modulus of Rupture
101
Seasoned MPa
MOE — Modulus of Elasticity
11.6
Seasoned GPa
Shrinkage — Green to 12% Moisture Content
7.8%
Tangential
5.5%
Radial
Dimensional change from green timber to 12% moisture content

*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.

Minimum Values for Strength Groups
Unseasoned Timber  |  Units: MPa = 145 lb/sq.inch
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
Minimum Values for Strength Groups
Seasoned Timber  |  Units: MPa = 145 lb/sq.inch
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
Shrinkage Classifications
Shrinkage from Green to Oven-dry (12% MC) – % before reconditioning
Description of Shrinkage Tangential Radial
Very Low0 – 3.50 – 2
Low3.5 – 5.02 – 3
Medium5.0 – 6.53 – 4
High6.5 – 8.04 – 5
Very High> 8.0> 5
Durability Classifications
Approximate service life (years)
Grade of Durability Fully Protected Above Ground, Exposed In-Ground, Exposed
Very Durable> 50> 40> 25
Durable> 5015 – 4015 – 25
Moderately Durable> 507 – 155 – 15
Non-Durable> 500 – 70 – 5
This species – Strength Group
SD4
Highlighted in the strength tables above
This species – Durability
Very Durable
Highlighted in the durability table above

Applications

Main Uses

Furniture Cabinet Making Interior Joinery Boatbuilding Musical Instruments Rifle Butts & Gunstocks

Stock & Sizes

Availability

Sawn 25mm, 40mm, 50mm and 75mm thicknesses in mixed widths.

Quality Standard

Grading

Grade Prime (FAS)