Tropical wood · Africa
African Pencil Cedar wood
African Pencil Cedar (Juniperus procera, family Cupressaceae) is a tropical timber from Africa. Green, its Janka hardness is 765 lbf (3,403 N), and air-dry it weighs about 36 lb/ft³ (577 kg/m³). The figures are from the USDA Forest Products Laboratory's Tropical Timbers of the World, pp. 437–438.
Other names, by country: 01 tarakwa, Mtarakwa, Mwangati (Tanzania).
Key numbers
- Janka hardness, dry
- Not printed
- Green: 765 lbf (3,403 N)
- As printed: “Janka side hardness 765 lb for green material.”
- Air-dry density
- 36 lb/ft³ (577 kg/m³)
- Basic specific gravity
- 0.48 oven-dry weight, green volume
- As printed: “Basic specific gravity (ovendry weight/green volume) about 0.48; air-dry density 36 pcf.”
- Shrinkage, green to 12% moisture content
- 4.5% tangential
- Radial 2.5%
One source: USDA Forest Products Laboratory, Tropical Timbers of the World (Chudnoff, 1979 edition), the only published source read for this wood
Strength
Bending strength is the modulus of rupture (MOR); stiffness is the modulus of elasticity (MOE); crushing strength is compression parallel to the grain. The sheet collects these from published tests: it prints 4 data sets, from different tests and sources, so they can differ widely; all are shown, in the sheet's order, each at the moisture content printed beside it, never restated as 12%.
| Moisture | Bending strength (MOR) | Stiffness (MOE) | Crushing strength |
|---|---|---|---|
| Green | 11,100 psi (77 MPa) | 1.28 million psi (8.8 GPa) | 5,800 psi (40 MPa) |
| Green | 10,000 psi (69 MPa) | 1.32 million psi (9.1 GPa) | 5,200 psi (36 MPa) |
| 12% MC | 14,100 psi (97 MPa) | 1.54 million psi (10.6 GPa) | 8,000 psi (55 MPa) |
| 12% MC | 13,800 psi (95 MPa) | — | 8,200 psi (57 MPa) |
A dash means the sheet prints no value; none is filled in.
What the data sheet says
- Color, grain and texture
- Heartwood pale red, yellow-brown, or purple-red, becoming a warm red-brown on exposure; sapwood narrow, whitish, clearly differentiated. Texture fine; grain straight; quartersawn boards have an attractive figure; noticeable cedar scent. Spiral grain, ingrown bark, and compression wood are common.
- Working properties
- Works easily with hand and machine tools; being fissile it tends to break and chip in drilling and mortising; glues well, takes an excellent polish; liable to split in nailing.
- Durability
- Heartwood is classified as durable and resistant to most forms of insect: attack.
- Uses
- Slats for pencil manufacture, furniture, joinery, cabinetwork, tanks and vats, shingles, millwork. Cedarwood oil is distilled from the sawdust.
- Where it grows
- East Africa; mainly in Kenya, Tanzania, and Uganda; found in the upland evergreen forests at elevations of 6,000-9,000 ft.
Quoted from Tropical Timbers of the World, pp. 437–438, a USDA Forest Products Laboratory work in the public domain.
Work it out for your project
- Rank woods for furniture with the species picker
Weigh african Pencil Cedar against other woods on hardness, weight, movement and color, every figure from the Wood Handbook.