cements, chinese glue - Cements, Chinese Glue; cements, chinese glue -
Shellac dissolved in alcohol. Used for joining wood, earthenware, glass, etc. This cement requires considerable time to become thoroughly hard, and even then is not as strong as good glue. Its portability is its only recommendation.
A colourless cem'ent, that is recommended highly for joining glass, crockery, stone, wood, leather, etc., is made by covering shellac with strong liquid ammonia, and shaking frequently until dissolved. The solution takes some time to form, and is facilitated by standing, placing the bottle (well stoppered) in a moderately warm situation, and briskly agitating it at intervals. It gives a strong waterproof cement, which adheres to everything. Bleached shellac gives a lighter coloured transparent solution, but the cement will not be so strong. Alcohol or wood spirit may be used in place of the ammonia, but the cement will not be so strong as where ammonia is employed.
Clean glass is reduced to very fine powder, and passed through a silken sieve; the powder is ground with white of egg on a stone slab, powdered glass being added till the required consistence is attained. It forms a very firm cement for glass and porcelain, vessels repaired with it breaking in a new place rather than at the joint.
3 oz. shellac, 1 oz. borax, ¾ pint water; the whole is boiled in a covered vessel till dissolved then evaporated to the proper consistence. It dries slowly, but is cheap and useful. Druggists and oilmen often employ it instead of gum, for fixing paper labels to glass or tin, when exposed to damp.
Bullock's blood is mixed with 1/5 its weight of quicklime. It will scarcely keep longer than a week when the weather is warm. For use, it is thinned by addition of a little water. It is employed by bookbinders and trunk makers.
Finest pale orange shellac, broken small, 4 oz.; rectified spirit (the strongest, 58 o.p.), 3 oz.; digest together in a corked bottle in a warm place until dissolved; it should have the consistence of treacle. For wood, glass, ivory, jewellery, and also fancy works.