Laminator Troubleshooting: Causes & Fixes

Not your exact symptom?

Describe it in the symptom finder and search the whole directory.

Problems on this page:

Bond strength too low Tunnelling or wrinkles Bubbles or spots in the laminate Coat weight varying Laminate curling Adhesive not curing Web breaks Rough or uneven slit edges Solvent odour in the laminate

Bond strength too low

Hits OEE: Quality

Symptoms: The two films peel apart easily in the bond test.

Adhesive coat weight too low

Check the coat weight against the specification and the metering settings.

Adhesive not fully cured

Check the curing room temperature and time before testing.

Mix ratio of a two part adhesive wrong

Check the mixing unit ratio and calibrate it.

Film surface treatment too low

Check the film treatment level before laminating.

Prevention: Bond strength tested after curing on each job.

Tunnelling or wrinkles

Hits OEE: Quality

Symptoms: Raised tunnels or wrinkles appear in the laminate.

Web tensions not matched between the two films

Balance the unwind tensions for the two materials.

Film curl or stretch different between webs

Check the films for curl and adjust tension.

Nip pressure uneven

Check the nip roller pressure across the width.

Adhesive too low in tack at the nip

Check adhesive temperature and type.

Prevention: Tension settings recorded per material pair.

Bubbles or spots in the laminate

Hits OEE: Quality

Symptoms: Small bubbles or uncoated spots spoil the look of the laminate.

Coat weight too low or uneven

Check coating rolls and the coat weight across the width.

Dust on the films

Clean the film path and use web cleaning if fitted.

Adhesive viscosity wrong

Check the viscosity at the coating unit.

Air trapped at the nip

Check the nip pressure and wrap.

Prevention: Appearance checked on each reel.

Coat weight varying

Hits OEE: Quality

Symptoms: Coat weight checks vary along or across the web.

Coating roll worn or damaged

Inspect the coating and metering rolls for wear, damage and dried adhesive.

Adhesive temperature changing

Keep the adhesive at a steady temperature, because its viscosity follows the temperature.

Line speed changing during the job

Keep the line speed steady, since coat weight changes with speed on most coating units.

Metering gap moving during the run

Check the metering roll gap and its locking, and measure it across the width.

Prevention: Coat weight measured at the start and end of each job.

Laminate curling

Hits OEE: Quality

Symptoms: Finished laminate curls when cut.

Tensions unbalanced between the webs

Balance the tensions so both films are stretched equally at the nip.

Heat applied unevenly

Check the heated rolls.

Rewind tension too high

Reduce the rewind tension.

Films with different shrinkage

Check material pairing with the supplier.

Prevention: Curl checked on sheets cut from each job.

Adhesive not curing

Hits OEE: Quality

Symptoms: The laminate stays tacky or the bond does not build after the curing time.

Curing room too cold

Check the curing room temperature.

Mix ratio wrong

Check the mixing unit.

Moisture affecting the adhesive

Keep the adhesive containers closed and check humidity.

Adhesive past its shelf life

Check the adhesive lot dates.

Prevention: Curing room temperature logged.

Web breaks

Hits OEE: Availability

Symptoms: The film breaks during running.

Tension too high for thin films

Reduce tension for thin films.

Damaged reel edges

Inspect reels before mounting.

Splice failures at the unwind

Check splice preparation.

Rollers not turning freely

Check idler rollers for drag.

Prevention: Web breaks recorded by cause.

Rough or uneven slit edges

Hits OEE: Quality

Symptoms: Reel edges are rough or the width varies.

Slitting knives blunt

Replace or sharpen the knives.

Knife position set wrong

Set the slitting knives with a gauge for the reel widths on the order.

Web wandering before the slitter

Check the web guide and its sensor.

Rewind tension wrong for the material

Check the rewind tension and taper settings for the laminate.

Prevention: Edge quality checked on each reel.

Solvent odour in the laminate

Hits OEE: Quality

Symptoms: The laminate smells of solvent or fails retained solvent tests.

Dryer temperature too low

Check the dryer zone temperatures.

Dryer airflow too low

Check the dryer fans and dampers.

Line speed too high for the dryer

Slow the line until the retained solvent passes.

Too much adhesive

Check the coat weight.

Prevention: Retained solvent tested on food packaging jobs; solvent areas use equipment rated for them and good ventilation.

Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.

Related equipment guides: slitter rewinder · flexo press · blown film line · offset press · die cutter · hot foil stamping machine · calender · glue spreader

Stop the same fault coming back

Recurring laminator stops usually trace to a cause you cannot see by hand. The partner we recommend is Fabrico: it tracks OEE and downtime live from PLCs, IoT sensors or AI cameras; where cameras are fitted, the video of a stop sits next to its machine data so the cause can be reviewed; and a technician opens the work order from the stop in the same system. Data is hosted in the AWS EU region, and Fabrico and the company behind it hold ISO/IEC 27001, ISO/IEC 20000-1 and ISO 9001.

Book a Fabrico demo

The directory stays free.

Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover