• Prerequisites: Part II, Zips, buttons, hooks and bars; Part VI, The fly-front zip, step by step for full zip replacement.
• Time: 5 minutes (button) to 1 1/2 hours (fly zip).
• Difficulty: easy (buttons) to moderate (zips).
• Tools: small pliers, seam ripper, zip foot, strong thread, spare sliders of the right size and type, hooks and bars, buttons, a jeans-button kit and hammer, safety pin or bodkin.
• Know the zip: metal, moulded plastic or nylon coil, and its size (often marked on the back of the slider). A new slider must match both.

1. At the top of the zip, unpick a little of the waistband or fly stitching to reach the top stops.
2. Remove one or both top stops with pliers (or cut through a moulded stop).
3. Slide off the old slider. Feed the new one on, both tapes into the slider evenly, with the pull tab facing out.
4. Run it down and up to check it closes the teeth.
5. Make new top stops: fit metal stops with pliers, or sew a firm bar tack across each tape just above the teeth.
6. Re-sew the waistband or fly stitching.

1. Note or photograph how the old zip sits; the old stitching lines are your guide.
2. Unpick the waistband for 2 in (5 cm) beyond the fly on both sides.
3. Unpick the fly topstitching and the zip from the fly facing and the fly shield. Keep the bar tack position marked.
4. Fit a new zip of the same type and length (or longer, to be shortened at the top).
5. Sew the zip to the fly shield side first, on the old line. Then to the fly facing, on the old line.
6. Re-topstitch the fly from the right side, following the old holes where possible. Add the bar tack.
7. Shorten at the top if needed, make new stops, and close the waistband.

For side and invisible zips, see Part VI, Side zips and invisible zips.

Jeans (tack) buttons:

1. Remove the old button and pin with pliers.
2. If the hole has torn, fuse a small square of interfacing or sew a denim patch inside first.
3. Push the new pin through from the inside, place the button cap on top, and set it with firm hammer blows on a hard surface. Or use a sew-on jeans button.

Hooks and bars: re-sew each hole with close buttonhole or blanket stitches through the waistband layers (not through to the outside on faced bands). Prong-type trouser hooks need their own setting tool; a sewn hook is the easy substitute.

Snaps (press studs): sew-on snaps with four or five stitches in each hole; for children’s trousers, check that small parts are secure (see Part I, Children’s clothing safety standards).

Elastic: open a small slit in the casing inside, pin the new elastic to the old, pull the old out so the new follows, overlap the ends 1 in (2.5 cm) and zigzag, close the slit.

Nada: pin a safety pin or bodkin to one end and work it through the casing; knot or add latkans to the ends so it cannot slip back.

• Zips that come apart at the bottom: trousers never use open-ended zips; a split at the bottom is a missing bottom stop or worn teeth.
• Stuck invisible zip: the coil may be caught; ease back gently, never force.
• Adaptive closures: replacing a button with a magnetic or Velcro closure for stiff hands; see Part III, Older bodies, seated and adaptive wear.
• Left-handed: fly direction is a style choice (traditionally left over right for men’s, sometimes the other way for women’s); when replacing, keep the trouser’s own direction.

• Match the zip: type, tooth size and colour; take the old one to the shop.
• Old lines first: following the original stitching hides the repair.
• Force: never pull a stuck slider hard; it tears the tape.
• Squeeze little, test often.

1. Rub a candle or soap on stiff teeth.
2. Use a pencil tip (graphite) on metal zips.
3. A key ring through the pull tab, hooked over the waistband button, keeps a creeping zip up.
4. Keep spare sliders in common sizes in your repair kit.
5. Sew a backing button inside for strained waistbands.
6. Use a toothpick to make a shank every time.
7. Close zips before washing to protect the teeth.
8. Dab clear nail varnish on button threads for a temporary hold (test on the cloth first).
9. Buy a slightly longer zip and shorten from the top; it is easier to fit.
10. Replace all hooks together if one has bent; the others will follow.
11. What professionals do differently: they try a new slider before replacing a whole zip.

The new slider will not go on

1. Check the size and type match the teeth.
2. Feed both tapes in at the same level and angle.
3. Prevention: take the old slider to the shop.

The squeezed slider jammed

1. Prise the plates open very slightly with a flat blade.
2. Fit a new slider.
3. Prevention: squeeze a little at a time.

The button pulled off with a hole

1. Fuse interfacing or sew a patch behind the hole.
2. Sew the button through a backing button.
3. Prevention: backing buttons on waistbands.

The jeans button spins or wobbles

1. Hammer again on a hard surface.
2. Replace with a new pin and button.
3. Prevention: set on a solid surface, not a table that flexes.

The new fly zip shows

1. Re-topstitch the fly a little further from the edge.
2. Press the fly facing so it covers the teeth.
3. Prevention: follow the old stitching lines.

The hook pulls through the waistband

1. Reinforce with a small patch of interfacing inside.
2. Move the hook slightly onto sound cloth.
3. Prevention: sew hooks through interfaced layers only.

New elastic twisted in the casing

1. Pull it straight from both ends and stitch through the casing at the side seams to hold it.
2. Re-thread with a wider safety pin.
3. Prevention: pin the elastic ends before closing.

• Myth: a split zip always needs replacing. Often only the slider is worn.
• Mistake: sewing buttons flat with no shank; they strain and pull off.
• Mistake: buying the wrong slider size.
• Mistake: forcing a stuck zip.

1. Beginner: sew five buttons with shanks on a scrap.
2. Improver: fit a new slider on an old zip and make new top stops.
3. Confident: replace a fly zip on jeans, following the old lines.

As a hobby: fastening repairs are the quickest way to bring a trouser back into use.

For earning: zip and button repairs are frequent, quick jobs; keep sliders and buttons in stock.

For teaching: a box of broken zips teaches diagnosis better than any diagram.

• Close zips and fastenings before washing.
• Check waistband buttons and hooks every few washes.

• Can you tell a worn slider from a broken zip?
• Can you fit a new slider and stops?
• Can you sew a button with a shank?
• Can you replace elastic in a casing?

Quiz

1. Teeth open behind the slider: what is the likely cause? Answer: a worn slider.
2. Why sew a shank? Answer: it gives room for the cloth under the button and reduces strain.
3. What keeps a creeping zip up quickly? Answer: a ring through the pull hooked over the button, or a locking slider.

• Slider: the part that opens and closes the teeth.
• Top and bottom stops: the metal or stitched ends that stop the slider.
• Shank: the thread stem under a button.
• Tack button: a jeans button fixed with a pin, not thread.
• Zip patti: a common tailors’ word for the fly area; local use varies.

• Main source: D&D’s own trousers ebook, chapters 61–62 (hardware is the most common failure; easy to replace; repair kit), widened with general repair practice.
• Squeezing sliders and setting jeans buttons depend on the hardware; teacher to check.