In using chemicals to stain woods it will be found that different pieces of the same kind of wood will take different shades; especially is this true in regard to oak.
To obtain an olive green on oak, use a saturated solution of iron chloride. When the wood comes out light a solution of tannic acid will darken it. Judgment must be exercised in the use of the tannic acid in respect to the strength of the solution. This will depend on the hardness and color of the wood. Different shades of green can be had by different strengths of solution.
To obtain a rich deep brown on oak, use iron chloride, and on that apply ammonium sulphide. If pieces in the work should be lighter, use tannic acid to darken.
To color whitewood a deep brown, first give a coat of tannic acid (five per cent solution), then a coat of iron chloride, then ammonium sulphide. Treat ash in the same manner (for brown) as whitewood.
To darken mahogany, use a five per cent solution of bichromate of potash. This will age it. When the bichromate solution is dry on the work, coat with a solution of red sanders. Bichromate solution is made from the crystals dissolved in water. The depth of color required will determine the strength of the solution. Red sanders solution is made by extracting the color from the powdered red sanders in alcohol. The depth of color required will determine the strength of solution.
To produce an old mahogany stain on mahogany and cherry, coat the work with a solution of bichromate of potash or ammonia, and, when dry, give it a coat of filler made in the following manner:
To make mahogany filler, add rose lake and drop black to light filler, and apply the same as ordinary filler.
To darken oak, use common lime made into a thin paste and apply. Let it stand a few minutes and rub off; if not dark enough, repeat the operation.
A rich brown is obtained by the use of iron chloride, ammonium sulphide, and burnt umber. The umber is made by mixing some of the powder in linseed oil and turpentine, or the umber ground in oil, thinned with turpentine, can be used. Apply in the order given above.
All work should be rubbed off with a soft cloth after oil or oil stain is applied. On all work where water or spirit stains are used, an oil-stain effect can be obtained by coating with linseed oil.
Fuming oak and other woods. The effect of fuming with ammonia is different on different woods (a little experimenting by the pupil will be of interest); especially is this true of oak. Red oak will not give such good results as white oak, and so it is with other woods.
In fuming, the work should be free from all grease or oil spots. The surfaces that are to be stained should be kept clear of all other surfaces, to allow free circulation of the fumes of the ammonia.
The work is placed in an air-tight box; an open vessel containing ammonia is also placed in the box with the article. The work is left until the desired color effect is obtained; a beautiful soft stain is the result.
To stain wood black, brush the wood over several times with a hot solution of logwood, and, when dry, apply a coat of a preparation made from powdered galls. Finish with wax. The logwood solution is made by boiling the logwood in water. The gall solution is made by using two ounces of powdered galls to one quart of water. The galls should be allowed to stand in the water from three to four days; a mild heat should be applied during this time.
Another method of ebonizing wood is to give the work a coat of extract of logwood (the hotter the better), and, when dry, apply a coat of acetate of iron (which is made by putting iron filings in vinegar or in a five per cent solution of acetic acid). After the second coat is dry, apply a coat of a solution made of sulphate of iron (two ounces to a quart of water).
A third method of ebonizing wood is to apply three or four coats of extract of logwood; develop the color by going over the work with a tincture of muriate of iron.
Another method of ebonizing wood. Boil one half pound of logwood in two quarts of water, add to this the peel or shells of walnuts, weighing about four ounces. Boil a second time and strain, then add one half pint of good vinegar and apply to the work when hot.
Aniline stains. From aniline dyes almost any color and shade can be obtained by combinations. Some of the colors are soluble in alcohol, some in water, and others are soluble in either water, alcohol, or turpentine.
In mixing for different shades, therefore, the liquid in which the color is soluble will determine which can be mixed together. Some of the colors require a mordant, and a solution of alum, vinegar, or copperas may be used.
The method of making a mahogany aniline stain is as follows: bismarck brown, 1/2 oz.; boiling water, 3 Pt.; or bismarck brown, 1/2 oz.; alcohol, 3 Pt.
All other aniline stains are made in this manner, substituting the liquid in which they will dissolve. Aniline stains should be kept in bottles, labeled, giving strength of solution (water, alcohol, or oil), so that no mistake can be made in using it.