Fig. 15.
The back knife, secured to the frame for trimming the base of the slug as it is carried past by the revolving wheel, should be kept moderately sharp and adjusted so as to fit closely against the back of the passing mold. Particular attention should be paid to this feature. The edge of the knife must bear uniformly across the face of the mold.
Fig. 16.
The front knives, between which the slug is ejected, should not be made too sharp. After being sharpened, the thin edge can be advantageously removed by the use of a thin oilstone applied against the side face; that is, against the face past which the slug is carried.
The stationary or left-hand knife should be so adjusted as to align exactly with the inner side of the mold. Under proper conditions this knife does not trim the side face of the slug, but acts only to remove any slight fins or projections at the front edge.
The right-hand knife, adjustable by means of a wedge and lever, should stand exactly parallel with the stationary knife. It trims the side of the slug on which the ribs are formed, and it serves to bring the slug to the exact thickness required.
FOOTNOTES:
[2] From Theodore L. De Vinne's Modern Methods of Book Composition, pp. 403-425. The Century Company, New York, 1904.