A representative piece of timber of a known moisture content that is placed in a stack, or a predryer or kiln charge, so that it may be removed for comparative examination, weighing, or testing during the drying process.
A comprehensive guide to the most common timber terms from A to Z.
Sample Board
Sap
The fluid in green wood that contains nutrients and other chemicals in solution.
Sapstain
A discoloration in the sapwood caused by the growth of fungi. Sapstain is often blue but can also be red, purple and other colours.
Sapwood
Outer layers of wood which, in a growing tree, contain living cells and reserve materials such as starch. Under most conditions the sapwood is paler in colour and more susceptible to decay than heartwood.
Sawed Veneer
Veneer produced by sawing
Sawn Timber
Timber finished to size with a saw.
Scarf Joint
A joint made by bonding two matching beveled ends or edges.
Scribe
To mark for an irregular cut.
Seasoned Timber
Timber that has been dried so that the maximum moisture content anywhere in the piece does not exceed 15%.
Seasoning
Drying timber to a moisture content appropriate to the conditions and purposes for which it is to be used.
Seasoning Stresses
Stresses in timber caused by variation in shrinkage as it dries.
Set
Permanent deformation in wood that occurs during drying when the tensile and compressive stress exceeds its elastic limit. Set prevents normal shrinkage of the timber and can lead to more obvious defects such as casehardening.
Set Compression
Occurs during compression, which tends to give the wood a smaller than normal dimension after drying. Compression set is usually found in the inner layers of wood during the later stages of drying, but sometimes occurs in the outer layers after extended conditioning or rewetting. Tension - Set that occurs during tension, which tends to increase the dimensions of the wood after drying. Tension set usually occurs in the outer layers of wood during drying.
Shake
Separation or breakage of the wood fibres caused by stresses in the standing tree or by felling and handling of the log. It is not caused by shrinkage during drying.
Shear
A condition of stress or strain where parallel planes slide relative to each other.
Shear Connector
A condition of stress or strain where parallel planes slide relative to each other.
Shear Panel
A selection of wall designed to resist lateral forces acting in, or parallel to, the plane of the wall
Sheet Metal Connector
A shaped connector made of sheet metal and perforated so that nails can be driven through.
Shrinkage
The reduction in dimension or volume which takes place in timber when the moisture content is reduced below fibre saturation point, expressed as a percentage of the original dimensions or volume. Linear shrinkage occurs in three directions radial, tangential and longitudinal.
Sill
The bottom member of a door or window frame. It is usually angled to shed water.
