CUTTING 311
and laid aside. A few sheets must be cut at full speed and carefully measured
and right-angled before doing the bulk, and the edges examined from time to
time for frayed or torn cuts.
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In cutting water-marked papers, the water mark has to be kept in correct
position on the sheet. This will often necessitate cutting a fraction over or
under the size, as the length between the water marks is liable to van7 a little,
especially in paper made on a machine with old-fashioned belt and packing
drive. A continual watch has to be kept as the sheets pass on the felt, and
any variation closely followed and corrected by the skilful use of the expanding
pulleys.
It will be recognized that the work of the cutterman, in keeping a good
and steady length, depends very much on the care taken by the machineman in
setting and working the dandy and the draws of the machine. It is advisable
to allow a fraction of an inch over the size—say, one-sixteenth—for the cut in
water-marked papers.
If the dandy roll cannot be made to register exactly the machineman should
notify his foreman, and also send a slip of paper with the reel, to warn the
cutterman what has occurred. If the length between water marks is too great, -
the sheet must be cut to register the water mark, and then trimmed on the
guillotine. If it is too short, die water mark will continually run out of register
and compel the cutterman to throw out sheets until it comes approximately
correct. It will be found on close examination that all water-marked papers
cut to register have some variation in length of sheet. This is inevitable to a
certain extent, and if the variation is less than \ per cent either way, the paper
may be considered commercially correct. If it is absolutely necessary to have
to supply a lot the exact size, the water mark on the dandy roll must be spaced
and tensioned to allow for trimming on the guillotine.
Haubold Supercutter.—This is a modern precision-built machine designed to
satisfy the demand for a cutter that will operate at high speed, cut with guil-
lotine accuracy and handle all classes of papers efficiently, whether large or small
orders. Cutting speeds of 600 ft. per minute and over are attained.
The machine comprises a heavy feeding press and cutting unit mounted on
robust side frames. The feeding press rolls are of special composition, ensuring
that all the webs of paper are fed uniformly to the cutting unit. The latter,
which is adjustable for true square cut, is driven through a positive, steplessly
adjustable gear which controls the speed of the rotating knife and thus enables
the length of ait to be accurately regulated.
The drive for the entire machine forms a totally enclosed unit which is
mounted on the cutter frame. Every step in the drive is positive so as to
avoid backlash, all main drives being effected through totally enclosed, precision,