Paragraph 52.

There are a great many different methods and processes of wood finishing, but they all have about the same purpose in view, that of bringing out and protecting the beauty of the wood. On any kind of woodwork which is exposed to outside weather conditions, some sort of paint is the common method of beautifying and preserving. A great many kinds of painting material have been used, and they are mixed in various ways to suit different special purposes, and while much of this is technical information, which belongs to the painters' trade, yet there are a few general rules regarding painting which can be easily understood. Wood exposed to the rain and snow, sunshine, wind and other weather conditions, if unprotected, will not last long. It absorbs moisture and swells, then shrinks when it is dried, and is constantly changing its shape and soon begins to decay. The purpose of the paint is to fill the tiny pores on the surface and provide a waterproof covering for the wood. Linseed oil and white lead have for many years been used as the principal ingredients of paint. Of course there are many other substances which have been added to change the color and the nature of the paint. Certain kinds of drying material and other secret preparations have been added, but the principal elements in the paint are still oil and lead.

Linseed oil is an oil pressed from the seeds of the flax plant; this oil is used either raw or boiled. The raw linseed oil is generally used in the first or prime coat on woodwork. The prime coat of paint is usually a thin coat, principally of oil, containing only a little lead; it should be evenly spread and well brushed into the pores of the wood.

It requires about three coats to do a first-class job of painting. The second coat contains considerably more lead and coloring material. The second coat should not be added until the first coat has become thoroughly dry. This coat should also be evenly spread. After the second coat has become thoroughly dry the third coat is usually added.

The third coat is often mixed with boiled oil, because this gives a little more gloss and a nicer appearance than the raw linseed oil. Sometimes a drier is added to the second and third coats of paints.

There are a great many kinds of excellent ready-mixed paints on the market, and for one who is not experienced and skilled in the mixing of paints it is much better to buy a ready-mixed paint and use it in accordance with the directions than to attempt home mixing.