On the usual method
there is no necessity for full or delicate control of lead mill engines;
but with this system it is essential, and the hydraulic reversing gear
contributes largely to such control. This may be explained as follows:
In all other mills with which the writer is acquainted, when the lead
sheet, or the original block, has passed through the rolls, and before
it can be sent back in the opposite direction, a man on either side of
the mill must work it into the grip of the rolls with crowbars.
In the writer's system this labor is avoided, and the sheet or block is
fed in automatically by means of subsidiary rolls, which are driven by
power. When it is required to cut the block or sheet by the guillotine,
or cross-cutting knife, instead of the block being moved to the desired
point by hand-labor, the subsidiary driven rolls work it up to the
knife; and such perfect control does the engine with its hydraulic
reversing gear possess, that should the sheet overshoot the knife
1/8 in., or even less, the engine would bring it back to this extent
exactly.
Another point, which the writer looks upon as one of the greatest
improvements in this mill, is its being furnished with circular knives,
which can be set to any desired width, and put in or out of gear at
will; and which are used for dressing up the finished sheet in the
longitudinal direction.
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