SECTION FOUR – OPERATIONAL ADJUSTMENTS
4.1 ADJUSTING LABEL TRACKING AND PRESENTATION TO PRODUCT
The tracking of the label through the machine is extremely important to consistent labeling. If the label web
“rides” up or down then the label will generally be skewed to one side or the other. The presentation of the
label to the product is also paramount. If the machine is set up correctly, the web will track consistently at the
same height through the machine riding on the web guides and around the peel plate and the label will be
presented squarely to the wall of the product to be labeled. With it set up this way consistent labeling will be
achieved. There are two major factors to consider in labeling consistency:
1.) THE LABEL WEB IS TRACKING UP AND DOWN
This changes the relative height on the product. If this is the case, then uneven pressure or pull is being
exerted on one or more points of the web which causes it to move up or down.
Here are some potential points to check:
• The web guides being out of alignment. (To correct please refer to section 3.4)
• The pinch roll being out of alignment and putting more pressure or not enough pressure on the
bottom (or top) of the web when it pinches. (Turn the stop screw located at the base of the
knurled roll to the right to increase pressure and to the left to decrease pressure.)
• The take-up reel being too high or low. (The take-up reel should be 2 inches from the base plate
to the top of the take-up reel plate.)
• The peel plate not being “square”. (To correct please refer to section 2.4)
• Pressure in the wrap station causes the bottle to “ride up” or corkscrew up which is reflected in
the skew of the label. (To correct please refer to section 2.5.)
Any of these factors will cause the label web to establish and track at an angle up or down. The obvious
symptom is skew of the labels in a predictable fashion, leaning to one side on the product in the same
way as each product that is labeled.
2.) THE SQUARENESS OF THE PEEL PLATE TO THE WALL OF THE PRODUCT
If the peel plate is angled versus the wall of the product, then the label will feed out angled onto the
container. This can be checked by using a square placed on the conveyor resting against the very end of
the peel plate. Place the square on the conveyor and reference it to the end and side of the peel plate.
There are two bolts where the label head is mounted to the stand. The label head pivots around the
larger bolt. Loosen both bolts and tilt the label station to achieve the desired adjustment. Adjust the
label station and move the label head until the end of the peel plate and the side of the peel plate are
square to the conveyor at the point of labeling. This will ensure that the label is feeding off the peel
plate in a straight fashion onto the product. Also check the turnbuckle adjustment.
There will always be some variance from label to label, which is due to the numerous variables of paper,
container, machine, etc. In an ideal world the variance will be normally distributed: for example, if 100
products are labeled, the skew will be equally on one side or the other with the average being exactly in
the middle (no skew). If plotted, it would appear as a bell-shaped curve. If the skew is always to one
side or the other then there remains some set-up problem or deficiency that is causing it.
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