BOB, a familiar name used at Birmingham, for small leather polishing wheels, with rounded edges, each made entirely of a thick piece of bull-neck, or sea-cow leather, perforated to receive the spindle, and used in polishing the insides of the bowls of spoons and other articles. See Wheels, article 52.
BONE. - After the turning tool or scraper has been used, bone is polished, 1st, with glass paper, 2ndly, with Trent sand or Flanders' brick with water on flannel; 3rdly, whiting and water on woollen rag; 4thly, a small quantity of white wax is rubbed on the work with a very quick motion, the wax fills the minute pores, but only a very small quantity should be allowed to remain on the work. Common bone works, such as nail and tooth-brushes, are frequently polished only with slaked lime used wet on flannel or woollen cloth.
BRITANNIA METAL works, like those in hard pewter, which this alloy considerably resembles, after having been turned are in great measure finished by the steel burnisher with an abundance of oil; the final lustre is usually given with rottenstone and oil on woollen rag. Frequently a very minute coat of oil is left as a defence to retard the action of the atmosphere, at other times the surfaces are thoroughly brightened with dry whiting, applied on wash leather.
Many workmen polish Britannia metal with Trent sand and oil, to the exclusion of all other applications. This sand is probably unequalled as to fineness.
The colours of bronzes, imitative of those tints which occur on the metal from long exposure to the atmosphere, are sometimes produced chemically in the modes to be subsequently described.
BRUSH WHEELS, circular revolving brushes are used with various polishing materials, see Wheels articles 65 and 66. Hand polishing brushes are also used, which are made almost like nail brushes, but many of them are longer, narrower, and also softer, especially such as are used by watchmakers, jewellers, and others.
BUFF LEATHER is used in various ways for polishing; thus it is glued on the circular edges or plane surfaces of wooden polishing wheels, and used with coarse emery, crocus, rottenstone, and other powders, see Wheels, article 5. Buff Sticks are parallel rods of deal upon which strips of buff leather are fixed, either by means of glue, or by folding the leather around the ends, and securing it by iron tacks. The buff sticks are principally used with crocus rottenstone, both with or without oil, and for most of the metals as well as various other substances; in some few cases the buff stick is moistened with water, see Tortoiseshell. Buff Wheels are described under the head Wheels, articles 51 to 53.