Читать книгу Finishing Techniques for Wood Crafters - Lora S. Irish - Страница 12

Wood naturally changes color with age, developing a darker tonal value patina. White pine, which has a very clear, white color when freshly cut, becomes a deep golden-yellow within a decade. Birch and basswood, both common pyrography woods, darken to a soft taupe or beige-brown color.

As wood ages, it can affect the quality of a work. For example, if you work a pyrography project with very pale tonal values, over time those values can become faded and completely lost. Painting will also be affected as

the wood slowly darkens and overpowers pale and pale-medium colored areas.

You cannot prevent wood from aging. However, you can take several easy precautions to minimize the effects of aging:

• For pyrography projects, check what patina coloration changes a wood will develop before you begin burning. If the wood will darken dramatically over time, work the burning in strong mid-medium to black-dark tones, avoiding the pale tonal range.

• Use a sealer that provides UV light protection. This reduces the oxidation that causes wood to develop a patina.

• Do not display or hang your work in full sunlight, for the same reason.

• Avoid using oil finishes on woods that have naturally dark patinas. For example, birch plywood can take on a soft beige tone when coated with Danish oil finish or tung oil. It naturally develops a deeper beige tone through aging patina. When combined, these two factors can totally block out mid-tone values within a few years.

“After the Rain” (top) was burned in 2017, whereas “Country Church” (above) was burned in 2001. Both were burned on birch plywood, and time has created a deep golden patina on the older piece.

Tip: You can buy a set of wooden tools designed for sculpting clay that will work wonderfully for burnishing—they can get into the sharp angles and deep carved areas of a project.

Burnishing can be a finish in its own right—no paint needed.

Burnish wood with a harder type of wood.

Burnished wood is very smooth and pleasant to handle.