The Janka Hardness Test is a measure of the
hardness of wood. The Janka Test was developed as a variation of the
Brinell hardness test. The test measures the force required to push a
steel ball with a diameter of 11.28 millimeters (0.444 inches) into the
wood to a depth of half the ball’s diameter.
The diameter was chosen to
produce a circle with an area of 100 square millimeters. The Janka
hardness values have been indicated below for your reference.
Janka Hardness is measured in the following units: In USA the Force unit is
pounds-force (
pounds-force is shown below), Sweden:kilograms-force, Australia:
newtons.
EXOTIC & DOMESTIC LUMBER JANKA VALUES
==============================
======
The
Janka hardness test measures the resistance of a type of wood to withstand denting and wear. It measures the
force required to embed
an 11.28 mm (0.444 in) steel ball into wood to half the ball's
diameter. This method leaves an indentation. A common use of Janka
hardness ratings is to determine whether a species is suitable for use
as
flooring.
The hardness of wood varies with the direction of the
wood grain.
Testing on the surface of a plank, perpendicular to the grain, is said
to be of "side hardness". Testing the cut surface of a stump is called a
test of "end hardness".
The results are stated in various ways, which can lead to confusion,
especially when the name of the actual units employed is often not
attached. In the United States, the measurement is in
pounds-force (lbf). In Sweden it is in
kilograms-force (kgf), and in Australia, either in
newtons (N) or kilonewtons (kN). Sometimes the results are treated as units, for example "660 Janka".
To convert pound-force (lbf) units to newtons (N) multiply pound-force by 0.45359237 then multiply by 9.80665 (1 standard
g in units of m/s
2). Janka hardness N = lbf × 0.45359237 × 9.80665
or multiply by 4.4482216152605. To get lbf from N, multiply N by 0.224808943099736.
The Janka Hardness test results tabulated below were done in accordance with
ASTM
D 1037-7 testing methods. Lumber stocks tested ranges from 1" to 2"
thick. The tabulated Janka Hardness numbers are an average. There is a
standard deviation associated with each species, but these values are
not given. It is important to note no testing was done on actual
flooring. Other factors affect how flooring performs: the type of core
for engineered flooring such as pine, HDF, poplar, oak, birch; grain
direction and thickness; floor or top wear surface, etc. The chart is
not to be considered an absolute; it is meant to help people understand
which woods are harder than others.
| Species |
Janka Hardness (pounds-force) |
| Australian Buloke |
5060[1] |
| Lignum vitae / Guayacan / Pockenholz |
4500 |
| Patagonian Rosewood / Curupay / Angico Preto / Piptadenia Macrocarpa / Brazilian Tiger Mahogany |
3840 |
| Brazilian Olivewood |
3700 |
| Brazilian Ebony |
3692 |
| Ipê / "Brazilian Walnut" / Lapacho |
3684 |
| African Pearlwood / Moabi Sometimes: Brazilian Cherry "Lite" |
3680 |
| Grey Ironbark |
3664 |
| Bolivian Cherry |
3650 |
| Lapacho |
3640 |
| Cumaru / "Brazilian Teak" sometimes: "Brazilian Chestnut," "Tiete Chestnut," "South American Chestnut," "Southern Chestnut" |
3540 |
| Ebony |
3220 |
| Brazilian Redwood / Paraju / Massaranduba |
3190 |
| Yvyraro |
3040 |
| Stranded/woven bamboo |
3000[2] |
| Bloodwood |
2900 |
| Red Mahogany, Turpentine |
2697 |
| "Southern Chestnut" |
2670 |
| Spotted Gum |
2473 |
| Brazilian Cherry / Jatoba |
2350 |
| Mesquite |
2345 |
| "Golden Teak" |
2330 |
| Santos Mahogany, Bocote, Cabreuva, Honduran Rosewood |
2200 |
| Pradoo |
2170 |
| Brazilian Koa |
2160 |
| Sucupira sometimes "Brazilian Chestnut" or "Tiete Chestnut" |
2140 |
| Brushbox |
2135 |
| Karri |
2030 |
| Sydney Blue Gum |
2023 |
| Bubinga |
1980 |
| Cameron[disambiguation needed] |
1940 |
| Tallowwood |
1933 |
| Merbau |
1925 |
| Amendoim |
1912 |
| Jarrah |
1910 |
| Purpleheart |
1860 |
| Goncalo Alves / Tigerwood |
1850 |
| Hickory / Pecan, Satinwood |
1820 |
| Afzelia / Doussie / Australian Wormy Chestnut |
1810 |
| Bangkirai |
1798 |
| Rosewood |
1780 |
| African Padauk |
1725 |
| Blackwood |
1720 |
| Merbau |
1712 |
| Kempas |
1710 |
| Black Locust |
1700 |
| Highland Beech |
1686 |
| Wenge, Red Pine |
1630 |
| Tualang |
1624 |
| Zebrawood |
1575 |
| True Pine, Timborana |
1570 |
| Peroba |
1557 |
| Sapele / Sapelli, Kupa'y |
1510 |
| Curupixa |
1490 |
| Sweet Birch |
1470 |
| Hard Maple / Sugar Maple |
1450 |
| Caribbean Walnut |
1390 |
| Coffee Bean |
1390 |
| Natural Bamboo (represents one species) |
1380 |
| Australian Cypress |
1375 |
| White Oak |
1360 |
| Tasmanian Oak |
1350 |
| Ribbon Gum |
1349 |
| Ash (White) |
1320 |
| American Beech |
1300 |
| Red Oak (Northern) |
1290 |
| Caribbean Heart Pine |
1280 |
| Yellow Birch, Iroko |
1260 |
| Movingui |
1230 |
| Heart Pine |
1225 |
| "Brazilian Mesquite" / Carapa Guianensis |
1220 |
| Larch |
1200 |
| Carbonized Bamboo (represents one species) |
1180 |
| Teak |
1155 |
| Cocobolo |
1136 |
| Brazilian Eucalyptus / Rose Gum |
1125 |
| Makore |
1100 |
| Siberian Larch |
1100 |
| Peruvian Walnut |
1080 |
| Boreal |
1023 |
| Black Walnut/North American Walnut |
1010 |
| Teak |
1000 |
| Cherry |
995 |
| Black Cherry, Imbuia |
950 |
| Red Maple |
950[3] |
| Boire |
940 |
| Paper Birch |
910 |
| Eastern Red Cedar |
900 |
| Southern Yellow Pine (Longleaf) |
870 |
| Lacewood, Leopardwood |
840 |
| African Mahogany |
830 |
| Mahogany, Honduran Mahogany |
800 |
| Parana |
780 |
| Sycamore |
770 |
| Shedua |
710 |
| Silver Maple |
700[4] |
| Southern Yellow Pine (Loblolly and Shortleaf) |
690 |
| Douglas Fir |
660 |
| Western Juniper |
626 |
| Alder (Red) |
590 |
| Larch |
590 |
| Chestnut |
540 |
| Hemlock |
500 |
| Western White Pine |
420 |
| Basswood |
410 |
| Eastern White Pine |
380 |
| Balsa |
100 |
| Cuipo |
22[1] |
References
- ^ a b Johnny W. Morlan. "Wood Species Janka Hardness Scale/Chart By Common/Trade Name A - J". The World's Top 125 Known Softest/Hardest Woods. Retrieved 20 December 2011.
- ^ "Bamboo Flooring". EcoTimber Flooring.
- ^ "Red Maple". The Wood Database.
- ^ "Silver Maple". The Wood Database.
External links
===============================
Woodworking Links
GLOSSARY OF WOOD TERMS
Maderas Brasileñas:Cumarú (
Dipteryx Odorata)
(teca brasileña, almendrillo, tonka, tonquin bean)
Ipe (ironwood)
Brazilian wood lumber
Ipe
Cumarú
Tigerwood
Massaranduba
Garapa
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