Wood Drying

Drying Techniques
FROM LOG ARRIVAL TO PLANING

Sawmill products in France are closely linked to the order of arrival of the logs. In France, drying is an essential step before going to the sawmill. Upon arrival of the logs, the products intended for sawing are sorted according to their quality and future destination. A portion must first dry using proven techniques depending on the species to obtain products in accordance with demand. The production of quality dry wood by an experienced forestry sector allows the realization of high-end products dedicated to joinery and cabinetmaking, construction, and the implementation of frameworks.

Why Dry Wood?
PROGRESSIVE ELIMINATION OF WATER ACCORDING TO NEEDS

In France, forests are sustainably managed. Environmental factors are not left to chance. The soil type obviously affects the moisture content of the species. The forestry sector is responsible for studying the soil type before cutting and specifying these conditions upon delivery to the sawmill.

Regardless of their uses in France, the species undergo transformations and adapt to construction or joinery. They are living materials that evolve with the surrounding environment. Indeed, when drying, wood loses volume and obtains a certain mechanical resistance easy to determine thanks to the technological means available in sawmills.

Equipping to Avoid Mistakes
REASONED CHOICE OF KILN TEMPERATURE

Natural wood drying is a specific treatment that depends on different criteria and is based on a certain duration. The moisture content is evaluated by applying a complex formula. In general, oak at the time of felling has a moisture content of 100%, beech 90%, and poplar up to 200%. Sophisticated devices are used for weighing and allow evaluating the right duration for each tree: 365 days on average for hardwoods, a season (about 6 months or 190 days) for softwoods like poplar or pine.

Artificial Drying Techniques
MORE OR LESS RAPID DEPENDING ON WATER EVAPORATION

Artificial drying techniques depend on the chosen treatment, the energy used, the type of heating, the log’s moisture content, and the treated species. The objective is to ensure a good material yield. Drying wood while maintaining a certain hygrometry level is essential. Several machines connected to computers provide precise indications and guide sawmill employees for each operation, from wood drying to sawing itself within the production unit. Drying takes place before or after the production of boards, beams, and other formats. The sawmill employees, in charge of this sensitive phase, have received complete training. They know how to analyze each step with precision and meticulousness.

Calculations to Perform
CHECK THE TEMPERATURE FOR RAPID TREATMENT

The temperature and humidity level of the storage room or kiln are calculated taking into account the needs of the species. Softwoods, for example, dry faster than oak. Another factor not to be neglected: the kiln capacity. The hygrometry level and duration are studied for a certain volume. An exceeded capacity leads to consequences on the resistance of dry wood and its aesthetics. The products are then no longer up to the expectations of joinery or construction professionals.

We therefore base ourselves on three main criteria: duration, energy, and type of heating. The energy required for drying is variable and is based on the heating power and the programmed duration.

To remember:

• Drying techniques are tested before being used.
• Production and realization are always based on complex studies and calculations.

Timber and Construction Wood in France
AVOID CRACKS AND OTHER VISUAL DEFECTS

Quality oak is used as construction wood and more particularly as timber wood. Well dry to the core, it does not undergo structural modifications. Impregnated with water, it gradually changes in volume. Drying therefore makes it possible to avoid sudden changes in volume and deformation, which is particularly serious on a framework.

Natural or artificial treatment lasts a certain number of days, generally several months, but it is much faster than what the ancients thought.

Sawing and planing waste is no longer really waste. A large part can be used for other purposes…
The Chauvin sawmill mainly processes only fir and spruce, harvested in the Jura forests between 700 m and 1300 m.

Avoiding Losses and Waste
AFTER SAWING, PLANING

The bark and chips resulting from sawing are treated separately to become heating solutions, to produce energy naturally. In sawmills, waste is non-existent or almost non-existent. Everything is reused. The products obtained, logs, chips, and pellets with high calorific energy value, are packaged in different ways to be easily stored by individuals. The production and realization of related products are carried out separately. There is a training course lasting several months allowing specialization in this field. This training is partly theoretical, partly provided in the workplace.

Work in a Sawmill
THE NEW GENERATION CHAUVIN SAWMILL IN THE JURA

The Chauvin sawmill, located in the heights of the Jura Mountains, is a perfect example of new-generation sawmills. Technology is used to offer professionals quality wood with drying studied according to the species, the recommended duration, and the desired results. The products obtained, for the manufacture of a framework, solid furniture or toys, for cladding or the design of innovative fuels, are easy to work with and exploit. Additional information can be obtained by simply completing the contact form provided on the website. The Chauvin sawmill meets the expectations of the most demanding.