Challenge Titan 265, Инструкция по эксплуатации

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7.0 Knife Installation/Changing
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7.3.1 Knife Blade Life
Knife blade life, or the time between sharpenings, can be affected by many factors. One important
factor is the type of paper being cut. Abrasive paper, such as recycled paper, soft paper such as
newsprint paper, and bound books can all significantly shorten knife blade life. Also, if the knife depth
is set too deep, the knife will cut too deep into the cutting stick and can dull the knife blade.
A knife can last anywhere between 2,000 and 5,000 cuts before it needs to be sharpened. Cutting
soft paper (such as newsprint paper) or paper with high post-consumer recycled content can cause
the knife to need sharpening after only 2,000 to 3,000 cuts. Cutting pure paper, such as bond paper
with no recycled content, or hard paper can allow the knife to be used for as many as 5,000 cuts
before it needs to be sharpened. In all cases, the operator should continually check the quality of the
cut to determine when the knife blade needs to be sharpened. Some characteristics that indicate a
blade needs sharpening are:
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The knife hesitates or stalls while making a cut.
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The sheets are not all cut to the same length (usually the top few sheets are longer than the
rest of the sheets - this is sometimes called “draw”).
•
Cut marks appear on the cut face of the paper.
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The profile of the cut (side view) is not perpendicular to the table.
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The cut does not appear straight when viewed from the top.
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The knife makes a “rougher” sound as it passes through paper.
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Nicks are visible on the cutting edge of the knife.
7.3.2 Cutting Stick
A worn cutting stick can affect the cut quality of the bottom sheets. When this happens, the cut stick
can be rotated. Usually, the stick should be rotated one or two times between knife sharpenings.
There are 8 possible cut stick positions. The stick can be rotated 4 times, and then turned end to
end, and rotated 4 times again.
7.3.3 Bevel Angle
Challenge recommends that bevel angles for the Titan 265 knives be in the range of 21° to 23°. In
general, a 21° bevel angle will provide better cut quality when cutting soft paper (such as newsprint),
recycled paper, or bound books. However, 21° angle knives can become dull sooner than 23° knives,
which results in shorter knife blade life. A knife with a 23° bevel angle, on the other hand, will not dull
as easily, and can provide satisfactory results when cutting most types of paper. Knives shipped with
the Titan 2 from the factory have a bevel angle of 23°.
7.3.4 Helpful Suggestions
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If your shop is large enough to purchase more than one set of knives, have one set beveled
at 21° and the other at 23°. Note: A set consists of 3 knives: one in the machine, one as a
back up, and one at the grinder.