Fundamentals Of Wood

Question 1

Wood microstructure

Answer 1

Cellular composition of wood consisting mainly of hollow tubes oriented along the length of the members resembling a bundle of straws glued together.

Question 2

Wood growth patternn

Answer 2

The properties of wood products relate directly to the natural growth of wood.
• Wood generally grows in a circular pattern;
• Seasonal change - different rates throughout each year
• Climatic change - different rates from year to year
• These different rates of growth produce the ring pattern found in all wood (more distinctive in softwoods).

Question 3

First year growth

Answer 3

First ring

Question 4

Rainy season growth

Answer 4

Thick ring

Question 5

Dry season growth

Answer 5

thin rings

Question 6

Spring yearly summer growth

Answer 6

Light coloured rings

Question 7

Late summer/fall growth

Answer 7

Thin dark rings

Question 8

Tree layers

Answer 8

Outer bark, inner bark, cambium, wood

Question 9

Heartwood

Answer 9

Inner core of wood, ceases to transmit moisture and hardens

Question 10

Sapwood

Answer 10

Outer layers of wood, continues to transmit moisture

Question 11

Hygroscopic

Answer 11

Ability to absorb moisture

Question 12

Anisotropic

Answer 12

Tends to Change dimensions at different rates in different directions

Question 13

When does shrinkage begin?

Answer 13

When moisture content falls below the finer saturation point

Question 14

Softwood saturation level

Answer 14

25 to 30%

Question 15

Hardwood saturation level

Answer 15

30 to 35%

Question 16

Seasoned wood MC content

Answer 16

19% or less

Question 17

Ways to season wood

Answer 17

Air drying, kiln drying

Question 18

Air drying

Answer 18

Reduces mc to 15 to 20%, takes 8 to 16 months

Question 19

Kiln drying

Answer 19

6-8 weeks

Question 20

Flat sawn (plain sawn)

Answer 20

Flat sawing of a large diameter log, in 2 directions yields several pice’s of dimension lumber and Timbers.

Small diameter, the sawing may be along one direction only, giving primarily dimension lumber.

Certain cuts have less stability

Question 21

Quarter sawn

Answer 21

All cuts have good stability

Primarily used for flooring

Question 22

X symbol

Answer 22

Surfaced or rough framing lumber /ontinuous member

Question 23

/ Symbol

Answer 23

Surfaced or rough framing lumber, interrupted member

Question 24

))) symbol

Answer 24

Worked or finish lumber

Question 25

1 inch

Answer 25

3/4 inch

Question 26

Softwoods vs

Answer 26

Mature 2 to 3 times faster than hardwood,
75% of North American forests
Framing

Question 27

Framing lumber

Answer 27

Soft, spruce pine fir, SPF

Question 28

Siding, paneling, fascia boards

Answer 28

Soft, s-p-f

Question 29

Shingles

Answer 29

Soft, cedars, redwoods, cypress

Question 30

Finished flooring

Answer 30

Softy southern pine, Douglas fir

Question 31

Doors and windows

Answer 31

Soft, pines

Question 32

Finished flooring

Answer 32

Hard, oak, maple, hickory, teak

Question 33

Paneling and finished folding

Answer 33

Hard, ash, beech, oaks, maples, pecan, walnut, teak

Question 34

Board thickness

Answer 34

<2 inches

Question 35

Dimensional lumber thickness

Answer 35

2 to 4 inches

Question 36

Timbers thickness

Answer 36

> = 5 inches