WOOD Flashcards
(28 cards)
What is the difference between wood, lumber, and timber?
Wood: the hard fibrous substance lying beneath the bark of trees
Lumber: wood sawn into construction members
Timber: lumbar 5 inches or larger in it’s least dimension
What does it mean to season wood?
To dry it out for you some construction… By air drying which takes several months and leaves 10 to 20% moisture in the lumber… or kiln drying which takes only a few days and leaves less than 10% moisture
In addition to less shrinkage, seasoned wood is better in these other ways than green wood
Stronger, left a bore thing, more fungi resistant, more decay resistant, more insect resistant, greater nail holding power, greater ability to hold paint
Three ways to quarter saw
Alternate, common, radial
Characteristics of plainsawed versus quartersawed lumber
Plainsawed: distinct grain pattern, susceptibility to twisting cupping and wearing unevenly, raised grain, shrinks and swells more in with, lesson thickness, left waste in cutting
Quartersawed: even grain pattern, less warpage, shrinks and swells morning sickness, lesson with, more waste in cutting, more costly
What is the difference between a peck and a pitch pocket?
A peck is a pitted area sometimes found in Cedar in Cyprus
a pitch pocket is an opening between growth rings containing resin
What is the difference between a shake and a check?
A check is a lengthwise green separation caused by seasoning… A shake is also a lengthwise green separation, between or through growth rings, but it is a natural defect
What is a split?
A manufacturing defect, a lengthwise separation of wood extending from one face to the other
If it is less than 2 inches thick it is a…
Board!
If it is 2 inches to 5 inches it is a…
Dimension lumber
What is yard lumber?
Used in general construction
What is factory and shop lumber?
Used for remanufacture into products… Like sashes and doors
How is selected would classed? And how is common lumber class?
Selective class from eight to D, common lumber is classed 1 to 5 in descending order to more and more blemishes
What is the difference between rough, dressed, and worked lumber?
Rough has visible saw marks, dressed is planed smooth in uniform sizes, and worked lumber is dressed and then tongue and groove, shiplapped or shaped in some pattern
What are all the plies called in plywood?
The face and the back on the outside, the core is the innermost, and the additional sheets are called crossbands
Plywood is particularly effective in resisting what kind of load
Lateral loads from wind or earthquake, in the form of roof and floor diaphragms and shear walls
How does interior and exterior plywood differ?
The type of adhesive used
What is A – D plywood?
It has an A grade face and a D grade back
Some structural plywood, such as for subflooring, is rated only with a…
Span rating … The first number identifies its maximum spacing over roof rafters, the second number over floor joists
What is bead board and what is it used for?
An insulating board with a core of small expanded polystyrene beads with heavy paper laminated to both sides… Used as perimeter insulation on foundation walls
Three grades of glulam
Industrial, architectural and premium is the tops. All having to do with appearance
How are the individual laminations of glulam joined?
Scarf joint and finger joints
What is laminated decking?
Layers of lumber bonded with adhesive. The interior surface is intended to be exposed, available smooth grooved prefinished or stained.
What causes wood decay?
Fungi that thrive in mild temperatures, moisture, and air
