6.
TROUBLE SHOOTING
6.1 SLITTING PROBLEMS
IMPORTANT NOTE: Condition of the log roll will affect quality of slit rolls.
Read the page headed “Principles of Single Knife Slitting”.
SLITTING PROBLEMS
– All Tapes
PROBLEM/EFFECT
CAUSE
REMEDIES
*
Tape tears as it is unwound.
This is sometimes referred
to as double cutting as the
knife makes two very small
cuts on entry into the tape
•
Knife diameter unsuitable
•
Always use your smallest
diameter knife
•
Knife
running
out
of
tolerance
•
Check backing plates and
knife surface are clean and
re-sharpen
knife
and
ensure it is running true.
•
Worn sleeves or poor fit
between sleeve and core
•
Replace mandrel sleeves
•
Speed
of
knife
entry
unsuitable
•
Slow down knife entry
speed
Slit roll “telescopes” after slitting
•
Log roll wound too tight
•
Rewind log roll to more
even tension
'Inside
of
cardboard
core
disintegrates' core collapses
making tape difficult to remove
off Mandrel.
•
Lubrication problem
•
Knife edge dull
•
Worn mandrel sleeve
•
Excessive spray on
cardboard cores when
slitting narrow widths.
Restrict spray or use
plastic cores (especially on
narrow widths)
•
Sharpen knife
•
Replace mandrel sleeve
Adhesive smearing on sides of
rolls.
•
Knife edge unsuitable.
•
Depends on product being
slit. Knife edges that are
very sharp can sometimes
cause this problem
– use
knife with rounded edge.
•
Knife lubrication problem.
•
Insufficient spray - must be
centralized down both sides
of knife.
•
Knife
or
chuck
RPM
unsuitable
•
Reduce knife or mandrel
RPM.
•
Knife angle incorrect
