Important: Safety Warning
This page describes practices involving highly flammable materials in ways that create a serious risk of fire or explosion.
In addition, this page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes.
This information has been left in for historical purposes but should not be acted upon.
Lacquering
Lacquers are varnishes applied upon brass, tin, and other metals to prevent them from tarnishing, and should always be applied soon after the process of bronzing or dipping. Their basis is a solution of seed-lac in alcohol. About 3 ounces of powdered shell-lac are added to a pint of the spirit, and the mixture allowed to digest with a moderate heat. The liquor, after being cleared by settling, is strained and poured off, and is then ready to receive the required coloring substances, the chief of which are annotto, dragon's-blood, gamboge, saffron, and turmeric.
If the brass or other metal to be lacquered be old and dirty, make a strong lye of wood-ashes, which may be strengthened by soap-less; put in the old brass-work, and the original lacquer and dirt will fall off. It must then be immersed in a mixture of nitric acid and water strong enough to eradicate the dirt; after which, wash in clean water, and it is ready for the lacquer. If the work is new, take off the dust and polish with chamois leather before applying the lacquer. The work to be lacquered must be subjected to a moderate heat; then, holding it in the pincers, apply the preparation with a soft brush, taking pains to cover the whole surface by a gentle pressure of the brush in one direction. The following are some mixtures for lacquers: Gold Lacquer.--Seed-lac, 3 ounces; turmeric, 1 ounce; dragon's-blood, 1/4 ounce; alcohol, 1 pint. Digest for a week, frequently shaking; decant and filter.
Dark Gold Lacquer.--Strongest alcohol, 4 ounces; Spanish annotto, 8 grains; powdered turmeric, 2 drams; red-sanders, 12 grains. Infuse and add shell-lac, etc., and when dissolved add 30 drops spirits of turpentine. Brass Lacquer.--Shell-lac, 8 ounces; sandarac, 2 ounces; annotto, 2 ounces; dragon's-blood, 1/4 ounce; spirits of wine, 1 gallon. Bronzed Dipped Work.--Alcohol, 12 gallons; seed-lac, 9 pounds; turmeric, 1 pound to the gallon; Spanish saffron, 4 ounces. If for a light lacquer, the saffron may be omitted.
Tin-plate Lacquer.--Alcohol, 8 ounces; turmeric, 4 drams; hay-saffron, 2 scruples; dragon's-blood, 4 scruples; red-sanders, 1 scruple; shell-lac, 1 ounce; gum-sandarac, 2 drams; gum-mastic, 2 drams; Canada balsam, 2 drams; when dissolved add spirits of turpentine, 80 drops.
Iron Lacquer.--Amber, 12; turpentine, 12; resin, 2; asphaltum, 2; drying oil, 6.
Iron Lacquer.--Asphaltum, 3 pounds; shell-lac, 1/2 pound; turpentine, 1 gallon.
Red Lacquer.--Spirits of wine, 2 gallons; dragon's-blood, 1 pound; Spanish annotto, 3 pounds; gum-sandarac, 4 1/2 pounds; turpentine, 2 pints. Made as pale brass lacquer.
Pale Brass Lacquer.--Spirits of wine, 2 gallons; Cape aloes, 3 ounces; fine pale shell-lac, 1 pound; gamboge (cut small), 1 ounce. Digest for a week, shake frequently, decant, and filter.
Pale Tin Lacquer.--Strongest alcohol, 4 ounces; powdered turmeric, 2 drams; hay-saffron, 1 scruple; dragon's-blood in powder, 2 scruples; red-sanders, 1/2 scruple. Infuse this mixture in the cold for 48 hours, pour off the clear and strain the rest; then add powdered shell-lac, 1/2 ounce; sandarac, 1 dram; mastic, 1 dram; Canada balsam, 1 dram. Dissolve this in the cold by frequent agitation, laying the bottle on its side to present a greater surface to the alcohol. When dissolved, add 40 drops of spirits of turpentine.