Wood Density
Species surface hardness
When working with various typese of woods, there is always the consideration whether we can substitute a less expensive wood for the species we are using and still get the same performance. When looking at a potential substitute, cost, availability, color and wood density can certainly be important factors.
The importance of wood density
Wood density is very important because this property is related closely to wood strength, stiffness and nail, screw and staple holding power. We can often offset low density effects. If the strength of the wood is low, we can perhaps make the piece of lumber a little larger. If the fastener holding power is low, we can increase the fastener size or number of fasteners to achieve the required performance.
One additional variable that is hard to compensate for by changing the design or manufacturing process is wood surface hardness. A low wood hardness, or softer woods, means that the surface is easy to dent; a dent can damage the wood fibers and give a brittle finishing coating. Crushed fibers can often be restored by steaming the damaged area briefly, finish repair is much more difficult. Softer woods, although they machine easier, are also harder to sand to a smooth finish and are more prone to have a fuzz.
Comparing wood hardness
Surface hardness in the wood industry is measured by the load or force required to embed a steel ball, 0.444 inch in diameter, to a depth of one-half its diameter. The hardness of end grain is different from the two surfaces. I have tabulated the surface hardness for various lumber species and arranged the list from softest to hardest, even within the groups. This arrangement is similar to a ranking of lightest to heaviest.
-
Tip: If you are making cuts in hardwoods, using cermet tipped saw blades may help lengthen the life of your saw blade.
The data, the average of both tangential and radial surfaces (flatsawn and quartersawn), but not end grain, are from the U.S. Forest Products Lab inMadison,WI.
I have divided the list into two parts: hardwoods and softwoods. The hardwoods, which are not necessarily hard, are trees with leaves while the softwood trees have needles.
Special note: Soft maple, a lumber trade name, includes both red and silver maple. Note the difference in hardness between the two species that make this grouping. Also note the large differences between the pine, spruce and oak species. ^
Wood Hardness
Here are two different lists for wood hardness by species. Both are “accurtate” and both were done according to scientific principles. However there are sub-species within species. Wood density or hardness also varies by location grown. Typically wood grown in a warmer climate with a longer growing season will be softer. Wood grown in a cooler climate with a shorter growing season will be harder. Condition of the soil and rainfall also influence the condition of the wood. Many tropical woods, for example, are described as being “full of sand” because of the high mineral content.
Hardwoods (Leaf Trees)
Very Soft (Under 450 Pounds)
Aspen
Basswood
Eastern Cottonwood
Quite Soft (450 To 600)
Butternut
Yellow-Poplar (Tulip Poplar)
Red Alder
Spanish Cedar
Moderately Soft (600 To 750)
Soft Silver Maple
Moderately Hard (750 To 900)
American Sycamore
True (Honduras) Mahogany
Tupelo
African Mahogany
Bigleaf (Oregon) Maple
Sweetgum
Slippery Elm
Hackberry
Quite Hard (900 To 1050)
Paper Birch
Cherry
Soft (Red) Maple
Teak
Black Walnut
Southern Locust
Very Hard (1050 To 1400)
Southern Red Oak
OregonAsh
Green Ash
Yellow Birch
Apitong & Keruing
Black Oak
Northern Red Oak
American Beech
White Ash
Rock Elm
White Oak
Bur Oak
Exceptionally Hard (Over 1400)
Hard Maple
Cherry-Bark Oak
Sapele
HoneyLocust
Swamp White Oak
Black Locust
Hickory
Pecan
Softwoods (needle trees)
Very Soft (Under 450 Pounds)
Northern White Cedar
Western Red Cedar
Atlantic White Cedar
Subalpine Fir
Eastern White Pine
Sugar Pine
Engelmann Spruce
Balsam Fir
Noble Fir
Western White Pine
Young Growth Redwood
Pacific Silver Fir
Quite Soft (450 To 600)
Ponderosa Pine
Old-Growth Redwood
White Fir
Lodge-Pole Pine
White Spruce
Red Spruce
Grand Fir
Eastern Hemlock
Bald Cypress
SitkaSpruce
Black Spruce
Western Hemlock
Red Pine
Jack Pine
AlaskaYellow Cedar
Tamarack
Moderately Soft (600 To 750)
Douglas-Fir, Interior
Spruce Pine
Loblolly Pine
Shortleaf Pine
Douglas-Fir, Coastal
Virginia Pine
Moderately Hard (Over 750 )
Western Larch
Longleaf Pine
Janka Scale Of Hardness for Wood Species
100 Balsa
350 Western Red Cedar
410 Basswood
420 White Pine
660 Douglas Fir
690 So. Yellow Pine (Loblolly & Short Leaf)
800 Honduran Mahogany
870 So. Yellow Pine (Longleaf)
950 Black Cherry
950 North American Cherry
1000 Teak
1010 Black Walnut
1010 North American Walnut
1100 Alpine Ash
1100 Heritage Oak
1100 Makore
1155 True Teak
1225 Heart Pine
1260 Red Oak
1260 Yellow Birch
1290 Angelique Teak
1290 Red Oak (Northern)
1300 American Beech
1320 White Ash
1350 Tasmanian Oak
1360 White Oak
1375 AustralianCypress
1400CaribbeanWalnut
1450 Hard Maple
1450 North American Maple
1500 Brazilian Maple
1510 Sapele
1630 Wenge
1686RoseRiverGum
1700 Locust
1710 Kempas
1720 African Blackwood
1725 African Padauk
1780 PauFerro
1820 Hickory
1820 Pecan
1820 Pecan
1860 Purpleheart
1910 Jarrah
1925 Merbau
1980 Bubinga
2023 Karri
2023 SydneyBlue
2046 Australian Beech
2135 Brushbox
2160 Goncalo Alves
2170 Asian Rosewood
2200 Bocote
2200 SantosMahogany
2300 CaribbeanRosewood
2345 Mesquite
2473 Spotted Gum
2820 Brazilian Cherry (Jatoba)
2900 Bloodwood
3000 Brazilian Rosewood (Tamarindo)
3190 Bolivian Cherry (Cerezo)
3220 Ebony
3540 Brazilian Teak (Cumaru)
3680 Brazilian Walnut (Ipe)
3800 Snakewood
4500 Lignum Vitae (Guaiacum Species Only)
Tags: hard wood, soft wood, types of wood, wood density
Leave a Reply