MSCE Woodwork flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Fall Protection Threshold

In general construction, fall protection is required at heights of 6 feet or more above a lower level. Guardrails, safety nets, and personal fall-arrest systems are acceptable systems.

Kickback

The sudden violent ejection of a workpiece back toward the operator, common on table and radial-arm saws. A riving knife, splitter, and anti-kickback pawls reduce the risk.

GFCI Protection

A ground-fault circuit interrupter trips when current leaks to ground. On construction sites it must protect 120-volt, 15- and 20-ampere receptacles not part of a permanent installation.

Ladder 4:1 Rule

For every 4 feet of working height, the ladder base is set out 1 foot from the wall. Extension ladders should extend at least 3 feet above the landing.

Nominal Versus Dressed Lumber

Nominal size is the rough name (2x4); dressed size is the finished dimension (1-1/2 x 3-1/2 in). Surfacing and drying remove roughly 1/2 in from thickness and width.

Moisture Content Formula

MC equals (wet weight minus oven-dry weight) divided by oven-dry weight, times 100. It is expressed as a percentage of the oven-dry mass of the wood.

Fiber Saturation Point

The moisture content at which cell walls are fully saturated but free water is absent, about 28-30%. Below this point, wood begins to shrink as it dries.

Equilibrium Moisture Content

The moisture content at which wood neither gains nor loses moisture to surrounding air. It tracks relative humidity and temperature, roughly 6-8% in heated interiors.

Penny Size (Nail)

A historical nail sizing system. Common conversions: 8d equals 2-1/2 in, 10d equals 3 in, 16d equals 3-1/2 in, and 20d equals 4 in.

Galvanized Fasteners

Zinc-coated fasteners required when connecting preservative-treated lumber. ACQ and CA treatments are corrosive; hot-dip galvanized or stainless steel is specified for exterior and wet use.

Dado Joint

A rectangular groove cut across the grain of one member to receive the end or edge of another. It provides alignment and load-bearing surface for shelves and cabinet sides.

Mortise and Tenon

A projecting tenon on one member fits into a matching mortise cut in the other. The joint resists racking and is common in timber framing and fine furniture.

Stud Spacing

The center-to-center distance between wall studs, typically 16 or 24 inches. Spacing must match the span rating of the sheathing and the load requirements of the wall.

Cripple Stud

A short stud placed above a header over a door or window opening, or below a window sill. It carries vertical load and supports sheathing and trim.

Header

A horizontal structural member spanning an opening to carry loads above it. Size depends on span, load, and species; doubled members are common over wide openings.

Rim Joist

The outermost joist running perpendicular to the floor joists, capping their ends. It ties the floor frame together and provides a nailing surface for sheathing.

Roof Slope

Rise over run, expressed as inches of rise per 12 inches of horizontal run. A 6/12 roof rises 6 inches for every 12 inches of horizontal travel.

Common Rafter Length

The line length equals the square root of run squared plus rise squared. Add the overhang and subtract the ridge allowance to obtain the cut length.

Collar Tie

A horizontal member connecting opposing rafters in the upper third of the span. It resists rafter separation and helps stiffen the roof frame.

Ice Barrier

A self-adhering waterproof membrane applied along the eaves before underlayment. It prevents water backup from ice dams in cold climates, extending about 24 inches inside the wall line.

Unit Rise

The height of a single step, equal to total rise divided by the number of risers. The IRC caps it at 7-3/4 inches for residential stairs.

Unit Tread Run

The horizontal depth of a single tread, equal to total run divided by the number of treads. Treads number one fewer than risers.

Stringer Length

The diagonal length of the stair carriage, equal to the square root of total rise squared plus total run squared. It sets the layout of the cut stringer.

Headroom Clearance

The vertical distance from the stair nosing line to the ceiling or obstruction above. Residential code requires a minimum of 6 feet 8 inches.

Sill Pan Flashing

A preformed or site-built flashing that lines the bottom of a rough window opening. End dams direct any water that enters back out to the exterior.

Shingle-Lap Flashing

A flashing sequence in which upper layers overlap lower layers so water flows outward and downward. The weather-resistive barrier laps over the window flange at the top and sides.

Window U-Factor

The rate of heat loss through a window assembly. Lower values mean better insulating performance; it is the inverse of R-value.

Drywall Screw Spacing

Screws are spaced 12 inches on center on ceilings and 16 inches on center on walls. Fasteners stay at least 3/8 inch from panel edges to avoid crushing the gypsum core.

Door Rough Opening

The framed opening that receives a door and jamb. For a standard interior door it is door width plus 2 inches and door height plus 2-1/2 inches.

Board Foot

A volume of lumber equal to 1 inch thick, 12 inches wide, and 12 inches long. It is computed as thickness times width times length divided by 12.

Drawing Scale

The ratio between a dimension on paper and the actual dimension. At 1/4 inch equals 1 foot, 1/4 inch on the drawing represents 12 inches of real construction.

Egress Window

An emergency escape opening required in sleeping rooms. It needs at least 5.7 square feet of clear area, 24 inches of height, 20 inches of width, and a 44-inch maximum sill.

Certificate of Occupancy

A document issued by the building authority after final inspection confirms the structure complies with approved plans and code. It legally permits occupancy of the building.