Cloudy, Wavy or Bubbled: Diagnosing a Bad Laminate

A laminating fault tells you what went wrong if you know what to look at. Almost everything comes down to temperature, speed or moisture.

Cloudy or milky finish

Cause: not enough heat. The adhesive has not fully melted and cleared.

Three things produce it:

• The machine had not finished warming up. Wait for the ready light, then wait another minute — the light usually indicates the elements are hot, not that the rollers are.
• The speed is set too fast for the pouch thickness. Slow it down or select the thicker setting.
• The pouch is thicker than the machine is rated for. No setting fixes this.

A cloudy laminate can sometimes be rescued by running it through again in the same orientation. If it clears, the cause was temperature and the setting needs changing.

Wavy or rippled edges

Cause: too much heat, or too slow. The film has over-softened and stretched as it passed through.

Increase the speed setting or select a thinner film setting. If the machine has only one temperature, let it cool for a minute between items rather than running a long batch continuously.

Waviness also appears when a thin document is laminated in a thick pouch — there is more film movement than the paper can restrain. Match pouch weight to document weight where you can.

Bubbles

Distinguish two kinds.

Small scattered bubbles

Usually moisture in the paper. Freshly printed inkjet output, or paper stored somewhere damp, carries water that turns to vapour at laminating temperature.

Let printed sheets rest for an hour before laminating, and keep paper somewhere dry. For heavily inked inkjet prints, longer.

Large bubbles or a trapped pocket

Air trapped when the document was placed in the pouch. Slide the document in flat, seat it against the sealed edge, and smooth it before feeding.

Wrinkles and creases

Cause: the pouch fed in crooked, or the document shifted.

Always feed sealed edge first. That edge holds the two films together and keeps them aligned as they enter the rollers. Feeding open edge first lets the two layers travel at slightly different rates, and that is a wrinkle.

Use the guide if the machine has one. If a document is much smaller than the pouch, it can slide during feeding — a carrier sleeve holds it in place.

Adhesive on the rollers

Cause: an open or trimmed pouch, or a pouch fed the wrong way round.

This is the fault that damages the machine rather than the document. Adhesive on hot rollers transfers to everything laminated afterwards.

Most machines can be cleaned by running a cleaning sheet through, or a folded sheet of thick paper, several times while hot. Never scrape a hot roller.

Prevention: never trim a pouch before use, never laminate an already-laminated item, and never feed the open edge first.

The item jams halfway

Use the release lever if the machine has one — it separates the rollers so the item can be pulled free. If it does not, switch to reverse where available.

Do not pull hard against engaged rollers. That is how drive gears strip.

After any jam, let the machine cool and check the rollers for residue before the next item.

Corners lifting after a few weeks

Cause: trimmed too close. The seal has been cut through, so the laminate is only held by adhesion to the paper, which fails at the corner first.

Leave 2 mm of sealed border, and round the corners.

A quick pre-flight

1. Machine at temperature, plus a minute.
2. Pouch thickness matches the machine setting.
3. Document rested if freshly printed.
4. Document seated against the sealed edge, smoothed flat.
5. Sealed edge fed first, straight.

Five checks, and they eliminate nearly every fault on this page. See our laminator range for machines with adjustable thickness settings and jam release.