The Manufacturer and Builder 9, 1887
3971. White Lacquer for Leather.
I would ask the favor of directions for preparing a white lacquer or enamel for leather that will not discolor. - B. F. W., Philadelphia.
Answer. The following receipt for a composition of this kind we take from the "Techno-Chemical Receipt Book": Precipitated carbonate of baryta is rubbed up with very light linseed-oil varnish, and the compound is applied to the leather. On this is laid a second coat prepared from carbonate of baryta and white copal varnish. When dry, the lacquer is pumiced with elutriated pumice stone and a piece of felt, and finally polished with elutriated bone-ash. It is stated that the white color of this lacquer is not affected in the least by sulphurous fumes, which will rapidly darken white lead.
3972. Colored Lacquer for Foil.
I notice that certain kinds of tinware and the pewter that is put over the corks of wine and liquor bottles, is made to look like brass. Can you tell me how it is done? - JAPANNED, New York.
Answer. There are a dozen different yellow or gold lacquers that may be used for imparting to tin or lead foil a gold or brass coloration. Any dealer in varnishes and lacquers will be able to furnish this orrespondent with a lacquer of the right color on demand. A very simple mode of doing the work himself, would be to heat some saffron in about five times its weight of distilled water, and as soon as it has about the right color, pour off the clear liquid and mix with it a little clear gum arable or isinglass solution. This liquor can then be applied with a brush, and when quite dry should be given a coat of clear lacquer.
3977. Ink for Etching on Glass.
If not too much trouble, I would like a formula for preparing a writing fluid for etching on glass directly. I believe there is an ink of this kind in the market, called "Diamond" ink, but I do not know where it can be obtained. - M. B. L., Big Bend, Ind.
Answer. An ink, or writing fluid, that can be used for etching directly on glass, may be made by the use of the the following ingredients, which are kept separate until the ink is required for use: A solution of ammonium fluoride, some sulphate of baryta, and sulphuric acid. When required, a portion of the sulphate of baryta is moistened with the fluoride solution, a few drops of the sulphuric, acid are stirred into the mixture, and the thin fluid paste is at once applied to the glass with a pen, with which the desired characters are written. The etching will be found to be sufficiently legible after the ink has remained on the glass for about an hour, when it is washed off. This preparation will corrode steel pens, but otherwise is free from objection. We do not know what the composition of "Diamond" ink is, nor where it is to be had.
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