The main line fuses, which protect the entire system from overloads, when blown, should be replaced by other fuses of the same rating.
The fuse for the mouth and throat heater circuit is for the purpose of protecting this circuit from accidents, and should always be replaced by another fuse of the same rating. This replacing of the fuses by others of the same rating is very important. On a 200 to 250-volt circuit, the main line fuses should be 10 amperes. The mouth and throat fuse, which is located in the control box above the magnetic switch, should be 3 amperes. On a 100 to 125-volt circuit the main line fuses should be 20 amperes. The throat and mouth fuse should be 5 amperes. Fuses of a greater amperage than those mentioned may cause the units to burn out or cause a fire hazard.
MOLDS
The various models of machines placed on the market today have a flexibility that requires a variety of molds to take care of the varying lengths and thicknesses of slugs. The molds are adjustable and are all removable from the mold disk should the occasion require. The molds are all constructed along the same general line, with a base and movable cap. The caps in all molds are held in place by two guides, pinned on each end of the base of the mold, and projecting into grooves in the cap.
The base of the mold is screwed firmly to the disk, and the two liners are held in place by the cap and the pressure from three screws which project through the rim of the mold disk. The cap and base being held parallel by the guides.
To change the mold from one size of body or length of slug it is only necessary to loosen the three screws, remove the liners and insert the ones desired. Do not pry the cap upward with a screwdriver inserted in the casting range of the mold cell. When tightening the screws in the rim of the disk, bring them just to a firm bearing. There is danger of cracking the rim if the screws are too tight.
The Universal Adjustable
The universal adjustable mold is the one most generally used. By removing the liners and substituting others, slugs of any length from 5 to 30 picas and from 5 to 14 points in body may be cast. All standard molds will cast 30-pica slugs.
The right-hand, or constant liner, is marked for thickness only. It is not necessary to change this liner unless the slug thickness is changed.
The left-hand liner is marked for thickness and length. The number stamped for the length, subtracted from 30, gives the length of slug which will be cast. For example, if a 13-em slug is wanted, use liner number 17, which allows the opening in the mold to be the required length. When ordering liners for these molds, always specify thickness and length of slug to be cast; also specify U. A. mold.