Hardwood Flooring February March 2018

VARIATIONS WITHIN SPECIES AND GRADES: In both true hickory and pecan hickory, there are often pronounced differentiations in color between spring wood and summer wood. In pecan, sapwood is usually graded higher than darker heartwood. Pecan and hickory are traditionally mixed by flooring mills. HARDNESS (JANKA): 1820. Pecan hickory is slightly softer than true hickories. DIMENSIONAL STABILITY: Average. This species is ranked among some of the least stable domestic species used in wood floors. Pecan hickory has a dimensional stability factor of 4.9 percent (radial) and 8.9 percent (tangential), meaning this species may shrink/swell up to 8.9 percent of its given width, depending on how it’s cut, when going from green (30 percent MC) to oven-dried. True hickory has a dimensional stability factor of 7.0 percent (radial) up to 12.6 percent (tangential), meaning this species may shrink/swell up to 12.6 percent of its given width, depending on how it’s cut when going from green (30 percent MC) to oven-dried. DIMENSIONAL CHANGE COEFFICIENT: Pecan hickory = .00169 (radial), .00315 (tangential) True hickory = .00259 (radial), .00411 (tangential)

SPECIFIC GRAVITY: Pecan hickory = .69 True hickory = .77 - .78

Nailing: Can be somewhat brittle, and has a tendency to split the tongues. Sanding: Difficult to sand because of density, and because light color makes sander marks show more than on some woods. Origin: North America. Readily available.

Sources: The Wood Database; Copyright © 2008-2016 Eric Meier | Wood Handbook (Wood as an Engineering Material) USDA Forest Products Laboratory

the magazine of the national wood flooring association

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