Vivid Ready

Making and mending

Repair a zip

Repair a zip: do this now

A zip that opens behind the slider almost never has anything wrong with its teeth. One minute with pliers fixes most of them.

  1. Run it closed and look along the teeth first. All present means it is the slider and this is easy.
  2. Opens behind the slider: squeeze the slider gently narrower with pliers, a fraction at a time, both sides evenly.
  3. Test after every squeeze. Too far and it jams or splits the tape.
  4. Stiff or stuck: check for caught fabric first, then clean the teeth and rub a pencil or candle along them.
  5. Never force a stuck slider. Free what it is caught on and work it back gently.
  6. Slider off one side: ease it back on at the bottom, then repair or replace the bottom stop.
  7. Missing tooth in the middle: a coil zip can sometimes be saved, a moulded or metal one cannot.
  8. Snapped pull tab is cosmetic. A split ring, a bootlace or a paperclip works indefinitely.
  9. Keep them working: close zips before washing, and clean and lubricate the teeth occasionally.
Commonest failure
A worn slider, not the teeth
Fix time
Under a minute
Coil zips
Sometimes repairable mid-run
Moulded or metal
A lost tooth is terminal

The mistake that costs lives: Throwing the garment out because the zip has gone. A failed zip takes a coat, a sleeping bag, a tent or a rucksack out of service completely, so the whole item goes, and the actual fault is usually the cheapest, softest, most replaceable part in the assembly: the slider has worn a fraction of a millimetre wider and stopped squeezing the teeth together. The teeth are fine. The tape is fine. The fabric is fine. Two seconds with a pair of pliers puts the whole thing back into service, and it is the repair almost nobody has been told about.

A zip that opens behind the slider almost never has anything wrong with the teeth. The slider has worn wider and stopped squeezing them together, and gently closing it with pliers fixes most zips in the house in under a minute.

A failed zip takes a coat, a sleeping bag, a tent, a rucksack or a pair of trousers out of service completely, and it is almost always thrown away as unrepairable. In fact the great majority of zip failures are one part wearing out, that part is the cheapest and most replaceable component, and the commonest repair of all needs nothing but a pair of pliers.

Work out which failure you have

Look at the teeth themselves before anything else. Run the zip closed and look along it: if every tooth is present and undamaged, the problem is the slider and this is an easy afternoon. If teeth are missing from the middle of the run, it is a bigger job.

The one minute fix

This is the repair that saves most zips and almost nobody knows it.

A zip closes because the slider physically squeezes the two rows of teeth together as it passes over them. The slider is made of softer metal than the teeth and it wears. Once its throat has opened up by a fraction of a millimetre, it passes over the teeth without pushing them into engagement, and the zip opens up behind it.

The fix is to close the slider back up:

  1. Open the zip fully and work at the bottom, away from the teeth.
  2. Take a pair of pliers, ideally with smooth jaws, or put a scrap of leather or cloth in the jaws to avoid marking.
  3. Squeeze the slider gently at the sides, top and bottom plate together, a tiny amount. A very small squeeze indeed. You are closing a gap of fractions of a millimetre.
  4. Test it. Run it up and down.
  5. If it still separates, squeeze a fraction more. If it has become too stiff to move, you have gone too far: ease it back open by inserting a flat screwdriver blade and twisting very slightly.

Squeeze both sides evenly. A slider squeezed on one side only will run crooked and chew the tape.

This works on metal sliders. On a moulded plastic slider there is nothing to squeeze and the answer is replacement.

It will not move at all

Do not force it. Forcing is what breaks teeth and tears the tape, and turns a five minute job into a replacement.

  • Look for caught fabric. Lining, a shirt tail, a drawcord. Ease it out gently, working the slider back a millimetre at a time rather than pulling.
  • Clean it. Old detergent, sand, salt and grit all bind a zip. An old toothbrush and warm water, then dry it.
  • Lubricate. A graphite pencil rubbed along the teeth is the traditional answer and works well. Candle wax, beeswax, soap or a silicone spray also work. Avoid oil on anything that will be against clothing, and avoid it entirely on a zip near a fire, because it collects grit.
  • Corrosion, particularly on brass zips that have been wet and put away: clean with a brush, then lubricate. Badly corroded zips will fight you forever.

The slider has come off

If it has come off one side only, the zip has usually just jumped the track.

Open it right down, work the slider off the bottom of the affected side completely, then feed that side back into the slider from the bottom. It needs the tape to go in straight and it often needs a bit of patience.

If it has come off entirely, feed both tapes into the slider from the bottom. The trick is getting both to start together: hold the tapes so the first tooth of each is level, and ease the slider on with the tapes pulled slightly apart.

On a jacket zip that separates at the bottom, check the retainer box and the insertion pin. If the box is torn out of the tape, that is a replacement zip.

A missing tooth

In the middle of the run, a missing tooth means the zip will always open at that point. There are two honest options.

Convert it to a shorter zip. If the damage is near the top, sew a new stop across the tape below the damage: a dozen tight whip stitches over the teeth, or a small metal stop crimped on. The zip now runs to that point and stops. On a sleeping bag or a bag this is often perfectly acceptable.

If the damage is in the middle of a jacket, replace the zip. That is a proper sewing job: unpick the old one, pin the new one in exactly the same position, and backstitch it in. It takes an evening by hand and it is very doable. See hand-sewing.

On a coil zip, where the teeth are a continuous nylon spiral rather than separate teeth, a displaced coil can sometimes be eased back into line with a needle and then the slider run over it slowly. Worth ten minutes before giving up.

The bottom has pulled apart

Common on jackets, and often mistaken for a broken zip.

  • The insertion pin has bent: straighten it carefully with pliers.
  • The retainer box has come loose from the tape: this can be stitched back if the tape is sound, using strong waxed thread and small tight stitches through the existing holes.
  • The tape has torn away at the bottom: reinforce with a patch of fabric stitched behind, then restitch the box.

A bottom stop on a non-separating zip (a trouser fly, a bag) can simply be replaced by a bar of whip stitches across the teeth. It does not need to be metal.

Replacing the slider

The proper repair when squeezing has stopped working, and much easier than replacing the whole zip.

  1. Identify the size and type. Sliders are marked with a number on the underside, usually 3, 5, 8 or 10, which is roughly the width of the closed teeth in millimetres. Coil, moulded plastic and metal tooth zips each need their own type of slider.
  2. Remove the top stops, which are the small metal or stitched blocks at the top of each tape. Pliers, carefully, or unpick the stitching.
  3. Slide the old slider off the top.
  4. Slide the new one on, the right way up, both tapes together.
  5. Fit new top stops, or, if you have none, sew a tight bar of whip stitches across each tape where the stop was. Thread stops work perfectly well.

Keep a few sliders in the sewing tin. They cost very little, they weigh nothing, and a size 5 coil slider fits an enormous proportion of jackets, bags and sleeping bags.

Keeping them working

  • Do not force a zip, ever. Stop, find what is caught, then continue.
  • Close zips before washing. An open zip flails about and bends teeth, and it snags everything else in the load.
  • Rinse salt and sand off the same day. Both are brutal on zips.
  • Lubricate once a season on anything that lives outdoors: a tent, a rucksack, a coat.
  • Support the tape when pulling. Holding the fabric just below the slider takes the strain off the tape and the stitching, which is where a hard-used zip actually fails.
  • Salvage the zip out of anything you discard. A dead coat is a full-length zip, two sliders and a retainer box, all of which are the parts you will want. See salvage in this domain.

Why this matters: overlooked supplies

Last reviewed 2026-08-03

Checked against 3 sources
  1. A zip closes because the slider forces the two rows of teeth or coils together as it passes; a slider worn wider than its original gap will pass over them without engaging
  2. Coil zips are continuous nylon spirals and can be repaired where a tooth is displaced; moulded plastic and metal tooth zips lose the tooth entirely and cannot
  3. The slider is the wearing part and is replaceable independently of the tape and teeth on most zips