Oak lexicon

What is wood moisture?

Wood behaves hygroscopically, i.e. it absorbs water from the surrounding air and releases it again. The water content in wood is referred to as wood moisture and is expressed as a percentage of the dry weight. This value has a considerable influence on the usability, durability and workability of wood.

What is Wood Density?

The density of wood describes the ratio of its mass to its volume and is given in kilograms per cubic meter (kg/m³). It indicates how heavy a specific volume of wood is and plays a key role in assessing properties like strength, hardness, and insulation capacity. Wood density varies depending on the wood type and moisture content and is an important factor in selecting wood for specific applications such as construction or furniture.

What is white cloud discoloration?

White cloud discoloration is an undesirable phenomenon that can occur when drying wood, especially oak. It manifests itself as uneven, cloud-like light spots on the surface of the wood. This discoloration usually occurs when the wood is dried too quickly or unevenly, resulting in different moisture zones. The risk is particularly high when drying in closed kilns without prior air drying, as the wood cannot release moisture evenly.

What is tannic acid?

Tannic acid, also known as tannin or tannin, is a fascinating class of polyphenolic compounds found in many plant species, especially trees. This substance is not only an essential component of plant defence mechanisms, but also a key element that contributes significantly to the longevity and robustness of wood.

What does "square-edged" mean?

Square-edged refers to a board that has been cut along the grain on both sides, resulting in a consistent width along its entire length. The processor of sawn timber has a significantly more accurate yield calculation when purchasing parallel-edged wood. This makes it easier to estimate costs for molding or furniture production. It's a crucial factor when comparing prices effectively.

What is solid wood?

Solid wood refers to wood that is cut from a single piece of the tree trunk without being broken down into smaller pieces or combined with other materials. This natural form preserves the original structure and grain of the wood and makes it a favoured material in wood processing.

What are the Shrinkage and Swelling Measures in Wood?

When we talk about wood, many people first think of warm colors, a pleasant feel, and a sense of nature. But wood can do even more - it “works.” This is precisely where the shrinkage measure and the swelling measure come into play. These two terms describe how much wood changes when it absorbs or releases moisture. And it’s not as complicated as it might seem at first glance.

What is a sawn veneer

Sawn veneer is a thin sheet of wood that is obtained by sawing a tree trunk. In contrast to other methods of producing veneer, such as peeling or slicing, sawing produces a rougher surface and a more pronounced wood structure. This method of production preserves the natural beauty and characteristics of the wood, which makes it particularly attractive for high-quality applications.

What is sapwood or heartwood?

When people think of wood, they often imagine a uniform material. In reality, however, a tree trunk consists of different zones that vary in their characteristics, depending on the tree species. In general, we distinguish between sapwood and heartwood, each fulfilling important functions in the tree and bringing its own specific properties for woodworking.

What is a rift cut?

The rift cut, also called radial cut or mirror cut, is a special way of cutting wood. The rift cut only produces planks with vertical growth rings, which result in high strength and a uniform tensile and shrinkage ratio.

What is Mass Density?

Mass density or particle density of wood describes the density of the pure wood material without any pores or cavities. It measures how heavy the wood itself is if all voids (lumina) within the wood were compressed to be nonexistent. The mass density is nearly the same across all wood types and is approximately 1.50 g/cm³. This value relates to the chemical components of wood, such as cellulose and lignin, independent of natural pore structures or external factors.

How is sawn timber measured?

The measurement of sawn timber is an important process in wood processing to determine the dimensions for sale and further processing. There are different methods depending on whether the timber is unedged, partially edged, or fully edged. Each of these categories has specific rules for measuring width, handling wane (bark edges), and accounting for splits.

What does wood with a live edge mean?

Wood with a live edge, also known as "live edge" wood, refers to wood products where the natural shape and contour of the tree trunk are preserved. Unlike fully trimmed wood, live edge wood retains the natural bark and outer form of the tree. This gives the wood a rustic and natural appearance, which is highly valued in furniture making and architectural applications.

What is Live Edge?

The live edge, also known as waney edge, natural edge, bark edge, or by the German term Baumkante, refers in woodworking to the natural edge of a wooden board or log. It replicates the naturally grown line of the tree trunk, thus preserving the original shape of the tree, including the bark and sapwood. The live edge imparts increased naturalness and individuality to the wooden workpiece, which is appreciated in both modern and traditional designs.

What is the Janka Hardness?

The Janka hardness is a method for determining the hardness of wood, indicating how resistant the material is to indentations. It measures the amount of force required to press a steel ball with a diameter of 11.28 mm halfway into the wood. The required force, measured in kilonewtons (kN), provides information on the wood's resistance to pressure marks. The higher the Janka value, the harder and more resistant the wood.