Fig. 16a.
A comparison of the old arrangement of inking rollers ([Fig. 16A]) with the new ([Fig. 16B]) is in itself an object lesson in this question of power and its economical application. It is but reasonable to suppose that the power required to move a set of rollers arranged in the old-fashioned manner ([Fig. 16A]) will be infinitely greater than that which would be needed for such an arrangement as shown in [Fig. 16B].
Fig. 16b.
Pursuing this matter still further, the question of indiscriminate damping presents itself. Granted that the influence here is an indirect one, yet it is a cause which frequently leads to an undesirable finish. Every printer knows something of the effect produced by excess of water upon printing inks. It hardens and stiffens them by accelerating oxidisation. In course of time their free working on the rollers is interfered with, and loss of power is by no means the worst result. Weak and impoverished impressions, abnormal wear and tear of the printing forme, and excessive saturation of the paper may follow.
In lithography generally, and in lithographic machine printing particularly, the damping of the stone is a matter which requires constant and careful attention; any arrangements for this purpose should therefore be as effective as possible. The damping rollers should be thoroughly cleaned each day, in order to remove any scum or grease which may have been collected from the printing forme.
Fig. 17.