Challenge CMT 330, Installation And Operator'S Manual

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APR 2018
CMT-330 Three Knife Trimmer 5-3 5. Book Quality
5.4 Rectangular Crease Lines
Description
Indentations or crease lines may appear in a
rectangular pattern in the center of the book.
Figure 5-4. Crease Lines on Cover
Possible Causes

The gripper has too much clamp pres-
sure for the stock being cut.
Solutions

Consult the CMT-330 Technical Manual
for this adjustment.
5.5 Linear Crease Lines
Description
Indentations or crease lines may appear in a
rectangular pattern near the edges of the book.
Figure 5-5. Linear Crease Lines
Possible Causes

Worn cut plates may create these lines
on the bottom cover.

The clamps have too much clamp pres-
sure for the stock being cut.
Solutions

Turn or change the cut plates.

If your machine is equipped with the op-
tional clamp pressure regulator, reduce
the clamp pressure by turning the con-
trol dial counterclockwise. Reduce the
pressure until crease lines disappear on
test books.
Note: Reducing the clamp pressure too much
will cause other quality problems such as draw.
Only reduce clamp pressure by necessary
amounts.
5.6 Draw
Description
The cut face appears to have a slope because
all of the sheets are cut at different lengths.
Figure 5-6. Draw
Possible Causes

Clamp pressure may be too low.

The knife may be dull.
Solutions

Check clamp pressure and/or system
pressure. Clamp pressure and system
pressure should be 80-90 PSI. Turn
control dial clockwise to increase pres-
sure. Make sure supply air is 80-90
PSI.

If the problem is on the face of the book,
replace all three knives. Rotate or re-
place the cut stick.

If the problem is on the top or bottom
faces of the book, replace the knives.
Rotate or replace the cut plates.