Violin Varnish and How to Make It/Chapter 7
CHAPTER VII.
Elementary Notes on Varnishing.
ALWAYS, before varnishing, apply a coat of a substance that will leave after dessication a colourless surface of rosin.
If your oil varnish dries too quickly, add more oil.
To make your varnish more siccative, add more rosin or gum to it.
By the addition of a proportion of essence of turpentine, a new produce will be obtained that will dry very rapidly.
To keep brushes in good order wash them carefully after using in a little turpentine or methylated spirit, according to the varnish you have been using.
After having prepared your instrument for varnishing, proceed as follows:—Place in a saucer a sufficient quantity of varnish to give a complete coat. Use a flat brush about 1 in. wide, and cover the instrument quickly, evenly and very thinly. When quite dry proceed with the second coat, and so on until you have obtained the depth of varnish and colour you require.
Always work in a dry room free from dust.
In winter the room should be warmed.
Spirit varnish must be very thin to be applied easily; hence, to acquire body and colour, 6 to 12 coats are necessary.
If each coating is polished before adding the next, an extra translucid varnish will be obtained.
To polish spirit varnish, use raw oil and finest Tripoli powder.
To polish oil varnish use water and finest pumice powder.
Always filter the varnish; this can easily be done with wool or fine cloth.
All gums used must be pure, and it is advisable to clean them before dissolving.
Add to the gum to be dissolved a small quantity of broken, not powdered, glass. The glass will get mixed with the gums and prevent it forming a solid mass, thus enabling the solvent to act more promptly. Two coats of oil varnish are sufficient.
To colour essence of turpentine dissolve in it some dragon's blood, etc.
Be very careful in the manipulation of the various ingredients when they have to be heated. Accidents will occur if proper care is not taken. Whenever possible the heating should be done out of doors.
Always heat liquids in a water bath.
Varnishes made with essence of turpentine are distinguishable by their fluidity, great brilliancy and quick drying qualities, but they are not very durable.
By the addition of siccative oil to them, the drying qualities are reduced, but greater durability is obtained.
Oil varnish forms a solid mass, and its clinging capacity is unequalled.
Anilyne dyes are not fast colours.