Essentials To Consider Before Wood Carving

A famous painter, when asked, 'How do I learn to paint?' answered: 'Take a canvas, take a brush, dip the brush in the paint and start.' Similar advice can be given in all seriousness to the aspiring carver, for the best teachers in the world are practice and, of course, the strong urge to fashion something for its own sake.

The study of wood has become a science in itself. Students who wish to go deeply into this subject can obtain detailed information from the Agricultural Research Service and the Forest Service divisions of the Department of Agriculture, Washington, D.C. Some general information, however, seems appropriate here so that the reader may gain a working understanding of his material.

A tree can be said to have three component parts: the root, the trunk, and the crown. The roots absorb water and chemical substances from the soil which are carried by the sapwood to the leaves and branches of the tree. The bark of the tree is for protection and insulation. The growth and thickness of the trunk is brought about by cambiumnial cells situated just under the bark of the tree.

Seasoning and shrinkage

In kiln seasoning, time depends on the density, thickness and water content of the wood. It is not advisable to use green, freshly cut timber for carving. The cells and the cell walls of this timber contain water. It is the process of drying out the free water in the cells, and the partial drying out of water in the cell walls, which is known as 'seasoning'.

It is obvious that when this water - which is after all a part of the tree's composition - is removed, shrinkage is bound to take place. Therefore the process must be controlled if distortion, cracks and splits are to be avoided. The two main methods of seasoning are air seasoning and kiln drying. The former is a slow method.

For instance, with 2-in. planks it will take over six months of good drying weather to reduce the moisture content of twenty per cent of their weight. For timber used in heated buildings it is necessary to reduce the moisture to about ten to twelve per cent.

The process of seasoning wood in a modern kiln can be achieved in a matter of weeks. In the case of tropical woods, air seasoning is favored, for periods up to two years. These can then be finally dried by the kiln method. There are a few woods that cannot be kilned at all as the cell walls of the wood collapse and render the wood useless.

The kiln

Very briefly, the kiln is a brick-built room with heating pipes generally in the ceiling. Fans are installed to keep the air moving and steam is introduced through a number of jets. The wood is stacked horizontally in such a way that the air can circulate freely. The planks themselves rest on 'sticks' or wood bearers of 1 in. X 1 in., spaced approximately 4 ft. apart for planks that are 2 in. thick or more. Regular tests of moisture content during kilning are made and the drying process is controlled by varying the humidity and the heat.

Once these fundamentals are understood, the beginner woodcarver may start his all important work of carving. Good luck!

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