7 min readConcept sheetOften a 5-mark answer each

Tentering and calendering

Tentering stretches damp cloth to its correct width and straight grain on a heated pin or clip frame. Calendering presses cloth between heavy rollers for smoothness, lustre or patterns.

Tenter (stenter) frameLong heated frame with pins or clips on moving chains

Sign of pin tenteringSmall pin holes along the selvedge

CalenderMachine of heavy, often heated rollers under pressure

Permanent calenderingOn thermoplastic or resin-treated fabrics

Tentering (stentering)

The phrase 'on tenterhooks' comes from the hooks of the old tenter frames.

1
Damp cloth from wet processing is fed onto two endless chains, one at each edge.
2
Pins or clips grip the selvedges. Pins suit knits and wool; clips leave no holes and suit heavy cotton.
3★
The chains move gradually apart, stretching the cloth to the required width, while weft straighteners correct bowed or skewed weft.
4
The cloth passes through a hot-air chamber and dries at this set width and straight grain.
5
The same frame is used to heat-set synthetics and to dry and cure chemical finishes.

★ one-way, controls the pace

Types of calendering

Type	How	Effect and examples
Simple (ironing)	Damp cloth passes between smooth heated rollers	Flat, smooth, slightly lustrous: sheeting, cambric
Friction (glazing)	A polished steel roller turns faster than the cloth and rubs it, often with starch, wax or resin	High polish: chintz, glazed cotton
Schreiner	A roller engraved with very fine diagonal lines presses the cloth	Soft, deep lustre: cotton sateen, table linen, nylon tricot
Embossing	A heated engraved roller presses against a soft roller	Raised patterns; permanent on thermoplastics or with resin
Moiré	Two layers of ribbed cloth pressed together, or an engraved roller	Wavy watermark look on taffeta and faille; permanent on acetate and synthetics

Tentering and calendering

TenteringWorks on width and grain: cloth is held at its edges, stretched and dried. A routine (general) finish.

CalenderingWorks on the surface: cloth is pressed between rollers. An aesthetic finish; temporary on plain cotton unless resin is used, permanent on thermoplastics.

In daily life

A glazed chintz table cover or curtain loses its shine after a few washes unless it is resin-finished, so read the label. Cloth that was not tentered straight twists after washing, which is why some uniform shirts have side seams that creep to the front.

Exam angle

2 marks: “What is tentering?” Tentering stretches damp fabric, held by pins or clips at the selvedges, to its correct width and straight grain while it dries in hot air.

5 marks: “Explain the types of calendering.” Define calendering; simple, friction (glazing), schreiner, embossing and moiré: how each is done and its effect; permanence on cotton vs thermoplastics.

Remember it

Tentering = tension sideways (width and grain). Calendering = compress (shine). Calender types: simple, friction, schreiner, embossing, moiré.