Gabarro

Douglas fir

Scientific name: Pseudotsuga menziessi Franco

Geographic origin: Northamerica (introduced in Europe, Australia, New Zeland)

Douglas fir
Description

  • Sapwood: Pale shade yellow
  • Heartwood: yellowish brown
  • Fiber: Straight
  • Grain: medium size to rough
  • Characteristic defects: thick and adhesive Knots

Capacity of being impregnated

  • Sapwood: From medium to low capacity of being impregnated
  • Heartwood: No capable of being impregnated

Mechanization

  • Sawing process: Easy and with no difficulties
  • Drying process: Easy. Low risk of crack formation.
  • Planing process: Easy and with no difficulties
  • Gluing process: Easy
  • Nailing and screwing process: No difficulties. Resistance to be pulled away.
  • Finish: No difficulties, although a blending agent should be applied in order to homogenize wood

Physical properties

  • Apparent density at 12% humidity
  • 510 kg/m3 semi-light wood
  • Dimensional stability
  • - Volumetric contraction coefficient 0,41% stable wood
  • - Relation between contractions 1,59% no tendency to deformity
  • Hardness (Chaláis-Meudon) 2,45 Semi-softwood

Douglas fir
Mechanical properties

  • Resistance to static flexion 860 kg/cm2 &;8226; Elasticity module 128,000 kg/cm2
  • Resistance to compression 525 kg/cm2
  • Resistance to parallel traction 930 kg/cm2

Douglas fir
Observations

  • The Sapwood has a very different colour