Oil and water stains, so called because of the solvent used, are the common kinds. Oil stains are easy to apply evenly and do not raise the grain of the wood, but they do not penetrate very deeply and are likely to give a muddy effect. Water stains, on the other hand, soak in readily, give a clear color, and are cheaper than oil stains, but raise the grain of the wood so that sandpapering a second time may be necessary. Water stains may be used on either hardwoods or softwoods, but as a rule oil stains are not so successful on hardwoods.
Both water and oil stains may be bought ready mixed, or some of the simple ones can be made at home. In any case, before using, the stain should be tested on an inconspicuous part of the floor or on a sample of the same kind of wood. If the color is too intense, the stain should be diluted with the kind of solvent with which it is mixed or with other suitable liquid. For example, an oil stain may be diluted with turpentine, and a water stain with water.
1 Adapted from Floors and Floor Coverings. Farmers' Bull. 1219. Bureau of Home Economics, U.S. Department of Agriculture, 1921. For formulas for making stains, varnish and varnish remover, and wax see ibid.
If an oak floor is to be water-stained, coating it first with clear water and sandpapering it smooth after it is dry will lessen the tendency of the stain to raise the grain of the wood. Oil stains will be absorbed more evenly by pine or maple floors if the wood is first coated with a mixture of 3 parts turpentine and 1 part linseed oil and the surface sandpapered smooth after it is dry.
Stains should be applied rather thinly with a clean brush or a sponge with even strokes taken parallel with the grain of the wood. With water stains especially, care should be taken not to let the strokes overlap, and the stained surface should be wiped at once with a soft cloth or cotton waste. Oil stains should be allowed to set for a few minutes before the surface is wiped. Two coats of light stain generally give a better effect than one coat of heavy stain. In general, 1 gallon of oil stain will coat about 400 square feet of floor once, depending, of course, on the depth of color desired and the texture of the wood.
After a floor is stained, it should be allowed to dry for at least 24 hours, and dust kept from it as much as possible. When thoroughly dry, it should be polished with a weighted brush covered with carpet, after which it is ready for the filler and wax or varnish.
Some of the very porous woods may be filled and stained at the same time by combining the stain and the filler, but generally a better effect is obtained by applying them separately.