• Prerequisites: Seams: plain, French and flat-felled.
• Time: overlocking a trouser takes about 15 minutes; Hong Kong binding 1–2 hours.
• Difficulty: overlock and zigzag easy; Hong Kong moderate.
• Tools: overlocker (3- or 4-thread) or a zigzag machine, pinking shears, bias tape or lining cut into bias strips, bias tape maker (optional).
• Safety: overlocker knives are sharp; keep fingers and pins clear. Never sew over pins on an overlocker.

Pinked:

1. Sew a row of straight stitching 1/4 in (6 mm) from the raw edge (this stops fraying past the pinking).
2. Trim with pinking shears just outside the stitching, using full-length strokes.
3. Press open.

Turned and stitched (clean finish):

1. Press the seam open.
2. Fold each raw edge under 1/8–1/4 in (3–6 mm), and press.
3. Stitch close to the fold through the allowance only, not through the trouser.

Bias tape (double-fold) binding:

1. Use ready-made double-fold bias tape, or make it from lining.
2. Slip the raw edge into the fold of the tape, the slightly wider side underneath.
3. Stitch close to the tape’s edge from the top, catching the underside.

Hong Kong finish:

1. Cut bias strips of light lining or silk 1–1¼ in (2.5–3 cm) wide.
2. Lay the strip right side to the right side of one seam allowance, edges level; stitch 1/4 in (6 mm) in.
3. Press the strip over the stitching, then wrap it round the raw edge to the back.
4. From the front, stitch in the ditch (in the groove of the first seam), catching the strip underneath. Leave the strip’s raw edge flat; bias does not fray much.
5. Press. Look for: a smooth, narrow, even binding with no twists.

• Four-thread overlock both sews and finishes a seam in one pass; good for joggers, leggings and children’s pull-on trousers.
• Three-thread overlock finishes single edges; use it for pressed-open seams.
• Selvedge as a finish: men’s waistbands and selvedge denim outseams use the selvedge itself.
• Festive and zari trousers: bind with soft lining so metallic threads do not scratch the skin.
• Children’s trousers: soft overlock or turned edges; avoid scratchy bound edges on the inner leg.
• Left-handed: overlockers and machines work the same; position yourself so you can see the knife clearly and guide with whichever hand is steadier. Pinking shears come in left-handed versions.

• Plan the finish before cutting: a French seam or Hong Kong finish needs no extra allowance, but flat-felled may need a wider one on one side.
• Overlocker tension: loopers should meet exactly at the edge. Loops on top: tighten the upper looper; loops underneath: tighten the lower looper. Change one dial at a time.
• Differential feed: raise it for knits that wave (stretch out), lower it for fine cloth that puckers.
• Speed: even and medium; jerky speed gives uneven stitch density.

1. Overlock flat pieces before sewing for pressed-open tailored seams; it is easier than finishing in a tube.
2. Match the thread to the cloth for the needle threads; loopers can be a neutral shade bought in large cones.
3. Tie a new colour on to the old threads and pull through, instead of re-threading the whole overlocker.
4. Do not trim tailored allowances when overlocking; set the knife to skim only.
5. Make bias tape from lining offcuts; it is softer and matches the lining.
6. Use tissue under fine cloth when zigzagging to stop tunnelling.
7. Finish the crotch together and press it towards the back.
8. Stop overlocking 1 in (2.5 cm) short of a seam that will be crossed; finish across it after.
9. Fray stopper on the end of every overlocked chain saves unravelling.
10. A Hong Kong finish in a contrast colour turns the inside of a trouser into a feature, popular in bespoke men’s trousers.
11. What professionals do differently: they choose the finish from how the trouser will be washed and whether it will be altered, not from habit.

The overlocked edge curls or waves

1. Adjust the differential feed (higher for waving).
2. Loosen the lower looper slightly.
3. Prevention: test on the same cloth and direction of grain first.

The overlocker cut into the trouser

1. Patch the cut from the inside with fusible interfacing, then resew the seam a little deeper there.
2. If it is in a visible place, add a design detail (a patch pocket, a piped seam) or recut the piece.
3. Prevention: keep the bulk of the trouser away from the knife, and stop to fold it back on tubes.

Zigzag makes the edge bunch (tunnelling)

1. Use a narrower stitch and an overcast foot.
2. Sew 1/4 in in from the edge and trim afterwards.
3. Prevention: test width and length on a scrap.

Pinked edges fray after washing

1. Overlock or zigzag over the pinking.
2. Bind the edges.
3. Prevention: use pinking only on firm cloth and lined or dry-cleaned trousers.

The binding twists

1. Unpick and resew with the strip eased, not stretched.
2. Press the strip before wrapping.
3. Prevention: cut strips on a true 45° bias.

The seam finish shows through on the right side

1. Press over a seam roll with a press cloth.
2. Change to a lighter finish (three-thread instead of four; Hong Kong in a thinner lining).
3. Prevention: test finishes on light cloth and look from the right side.

The overlocker chain unravels

1. Thread the chain back under the stitches with a large-eyed needle.
2. Seal with fray stopper.
3. Prevention: finish every end as you go.

• Myth: you need an overlocker to make good trousers. Zigzag, pinked and bound finishes were used for generations.
• Myth: overlocking alone holds a seam. A 3-thread overlock is a finish, not a seam; always sew the seam with a straight stitch first.
• Mistake: finishing alteration seams together, so they cannot be let out.
• Mistake: sewing over pins on the overlocker; it damages the knife.

1. Beginner: overlock or zigzag ten 12 in (30 cm) edges; aim for even width.
2. Improver: add five finishes to your seam sampler card.
3. Confident: Hong Kong-finish the side seams and inseams of an unlined wool trouser.

As a hobby: a beautifully bound inside is a private pleasure every time you hang the trouser up.

For earning: offer finishes as quality levels (standard overlock, bound, Hong Kong), each costed by time.

For teaching: let learners thread an overlocker from scratch at least once; it removes the fear of the machine.

• Check overlocked edges for broken loops after the first wash.
• Bound seams on wool trousers prefer dry cleaning or gentle hand washing.
• Clean lint from the overlocker after every trouser; it collects heavily.

• Can you pick a finish for a jeans, a silk palazzo and a men’s wool trouser?
• Do you finish alteration seams separately?
• Can you adjust overlocker tension one dial at a time?
• Can you sew a Hong Kong finish?

Quiz

1. Which finish is the standard in ready-made clothes? Answer: overlocking.
2. Why stitch before pinking? Answer: so fraying stops at the stitching.
3. What width bias strip suits a Hong Kong finish? Answer: about 1–1¼ in (2.5–3 cm).
4. Is a 3-thread overlock a seam? Answer: no, a finish; sew the seam first.

• Overlock (serge): a looped stitch that trims and wraps the edge.
• Differential feed: overlocker setting that stretches or gathers as it sews.
• Tunnelling: cloth bunching under a zigzag.
• Pinking: cutting a zigzag edge.
• Hong Kong finish: a bound edge with the binding’s raw edge left flat underneath.
• Stitch in the ditch: stitching in the groove of a seam.

• Main source: D&D’s own trousers ebook, chapter 41 (finishing methods), with general, widely taught practice.
• The name “Hong Kong finish” is widely used; its origin is traditionally linked to Hong Kong tailoring, but accounts differ.
• Teacher to check: D&D’s standard finish for each trouser type.