Wood species
Tornillo wood
Tornillo is a hardwood (Cedrelinga cateniformis). Its Janka hardness is 870 lbf (3,870 N) green; the Handbook prints no dry value and it weighs about 34 lb/ft³ (543 kg/m³), 2.8 lb (1.28 kg) per board foot.
Also called: cedro-rana.
Key numbers
- Janka hardness, 12% MC
- Not measured
- Green: 870 lbf (3,870 N)
- Weight at 12% MC
- 34 lb/ft³ (543 kg/m³)
- Handbook estimate (Eq. 4-13): no shrinkage is published
- 2.8 lb per board foot
- Specific gravity (oven-dry weight)
- 0.45 on green volume
- Shrinkage, green to oven-dry
- Not measured tangential
One source: USDA Forest Products Laboratory, collected from the world literature (its Tables 5-5 and 4-4)
Why: From the USDA Wood Handbook, which collected these values from the world literature; tornillo's density is worked from its specific gravity with the Handbook's own equations.
How much tornillo moves
The 2021 Wood Handbook prints no shrinkage or movement coefficient for tornillo, so this page gives no movement figure rather than borrow one from another species.
Color, grain and working
- Color
- Pale brown with a golden luster and prominent red vessel lines.
- Grain and texture
- Coarse texture.
- Working and character
- Strength comparable with American elm. Cuts easily and finishes smoothly, though tension wood can leave woolly surfaces. Fairly durable.
- Uses
- General construction and lower-grade furniture parts.
The Handbook prints only green-wood values for tornillo, and no shrinkage.
Adapted in our own words from the Wood Handbook, Chapter 2, p. 2-38.
Strength
Bending strength is the modulus of rupture (MOR); stiffness is the modulus of elasticity (MOE). Values for tornillo from Wood Handbook Table 5-5b (p. 5-25), which the Handbook says were collected from the world literature, on clear, straight-grained specimens. Knots and cross grain make lumber weaker than these clear samples (Handbook Chapter 5).
| Property | Green | 12% MC |
|---|---|---|
| Bending strength (MOR) | 8,400 psi (58 MPa) | — |
| Stiffness (MOE) | — | — |
| Crushing strength (compression parallel to grain) | 4,100 psi (28 MPa) | — |
| Shear parallel to grain | 1,170 psi (8 MPa) | — |
A dash means the Handbook prints no value; none is filled in.
Dust and health
- Wood dust is classed as carcinogenic to humans (Group 1) by the International Agency for Research on Cancer, chiefly for cancers of the nose and sinuses.
- NIOSH recommends keeping wood dust exposure to 1 mg/m³ of total dust, as quoted in OSHA's sawmill guidance.
This is what the named authorities publish, not medical advice.
Compare with
Why these numbers
Why these numbers?
The situation
The Wood Handbook prints tornillo's side hardness as 870 lbf for green wood; dry it is not measured (Table 5-5b, p. 5-25 shows "—"), so no dry value is given here.
One source: USDA Forest Products Laboratory, collected from the world literature (its Tables 5-5 and 4-4) , sources [1]
What that means
Side hardness (Janka) is the load needed to press a 0.444 in (11.28 mm) steel ball halfway into the wood across the grain; a higher number dents less (Handbook p. 5-5).
One source: USDA Forest Products Laboratory, collected from the world literature (its Tables 5-5 and 4-4) , sources [1]
So
The Handbook gives only the green specific gravity (0.45) for tornillo, so it is moved to 12% with the volumetric shrinkage of undefined% (Eqs. 4-9 and 4-11), then multiplied by water's density and 1.12 (Eq. 4-14).
Arithmetic: exact by definition , sources [1]
The number
About 34 lb/ft³, or 2.8 lb per board foot (1/12 ft³), at 12% moisture content.
Arithmetic: exact by definition
Sources