Sweetgum
Liquidambar styraciflua
Sweetgum measures 850 lbf on the Janka scale, 34% softer than northern red oak.
- Bigleaf maple and black ash have exactly the same Janka figure.
- Across all 155 woods it falls in the top fifth for face shrinkage, radial shrinkage and volumetric shrinkage.
- On the Janka scale its nearest neighbours are western larch at 830 lbf and slippery elm at 860 lbf.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
SweetgumU.S. hardwoods medianOther woods
Shrinkage across the face
10.2%radial 5.3%21st highest of 1553.5%12.7%Cupping tendency
1.9255th highest of 1551.092.90Density
0.460.52 at 12% MC58th lightest of 1550.250.96Janka hardness
850 lbf3,781 N68th softest of 15538th of 53 U.S. hardwoods; 27% below the U.S. hardwoods median240 lbf3,680 lbfBending strength
12,500 psi86.2 MPa69th weakest of 1554,300 psi29,900 psiStiffness
1.64 M psi11.3 GPa76th stiffest of 1550.54 M psi4.06 M psi
How much it moves
Its face shrinkage of 10.2% is in the top quarter of the list, with an ordinary T/R ratio of 1.92.
0.61 in.
off a 6-inch flatsawn board, green to oven-dry; quartersawn 0.32 in.
- Tangential
- 10.2%
- Radial
- 5.3%
- Volume
- 15.8%
- T/R ratio
- 1.92 (98th most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- Slippery elm
1% harder · 4% heavier · shrinks 1.3 points less across the face
- Cucumbertree
18% softer · 4% lighter · shrinks 1.4 points less across the face
- Black maple
39% harder · 13% heavier · shrinks 0.9 points less across the face
Woods of similar hardness
The eight nearest on the Janka scale, lbf.
Laboratory values
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Tension perpendicular | 540psi | 760psi | +41% | 5.20MPa |
| Compression perpendicular | 370psi | 620psi | +68% | 4.30MPa |
| Compression parallel to grain | 3,040psi | 6,320psi | +108% | 43.6MPa |
| Impact bending | 36in. | 32in. | −11% | 813mm |
| Side hardness | 600lbf | 850lbf | +42% | 3,781N |
| Modulus of rupture | 7,100psi | 12,500psi | +76% | 86.2MPa |
| Shear parallel to grain | 990psi | 1,600psi | +62% | 11MPa |
| Modulus of elasticity | 1.20M psi | 1.64M psi | +37% | 11.3GPa |
| Work to maximum load | 10.1in-lbf/in³ | 11.9in-lbf/in³ | +18% | 82kJ/m³ |
Wood Handbook Table 5-3b, Table 4-3. Data & method · Guides