6.3 Hairstyling & Thermal Styling

6.3 Hairstyling & Thermal Styling

Pin Curl Construction & Mobility Principles

Pin curls serve as the foundation for wet styling, pattern setting, and vintage hair design. Understanding the structural components of a pin curl allows cosmetologists to engineer precise curl direction, volume, and movement.

The Three Structural Components of a Pin Curl

1. Base: The stationary, non-moving foundation of the curl located directly on the scalp. It serves as the panel of hair upon which the pin curl is constructed.
2. Stem: The section of hair between the base and the first arc or turn of the circle. The stem gives the curl its direction, mobility, and movement.
3. Circle: The part of the curl that forms a complete circle and ultimately produces the wave or curl pattern. The size of the circle determines the width of the wave and the overall tightness of the finished curl.

Pin Curl Stem Mobility Gradations

The degree of movement in a pin curl is governed entirely by the length of its stem:

• No-Stem Curl: Placed directly on its base. It produces a tight, firm, long-lasting curl with maximum holding strength and minimum mobility.
• Half-Stem Curl: Placed half off its base. The stem permits a medium amount of movement while giving the curl good holding power and medium volume.
• Full-Stem Curl: Placed completely off its base. The stem allows maximum movement and flexibility, enabling the hair to lay flat or swoop into smooth waves, but provides minimum holding strength and curl control.

Shaping & Pin Curl Types

A shaping is a section of hair molded in a circular motion in preparation for forming pin curls.

• Open-Center Curls: Produce smooth, even waves and uniform curls.
• Closed-Center Curls: Produce waves that decrease in size toward the end, ideal for fine hair or achieving fluffy volume.

Pin Curl Mobility & Base Placement Matrix

---

Roller Base Placement & Volume Dynamics

Roller sets provide faster styling and greater volume than wet pin curls. The amount of volume, lift, and strength achieved depends on base control—the position of the roller relative to its base panel.

The Three Standard Roller Placement Positions

• On-Base Placement (Full Base):
  • Technique: The hair subsection is overdirected forward beyond 90 degrees (elevated approximately 45 degrees past perpendicular) from the scalp before rolling.
  • Result: The roller sits directly on its base. Produces maximum volume, full root lift, and maximum base strength.
• Half-Base Placement:
  • Technique: The hair subsection is held straight up at a 90-degree angle (perpendicular to the scalp) before rolling.
  • Result: The roller sits half on its base and half off its base. Produces medium volume and moderate root movement.
• Off-Base Placement:
  • Technique: The hair subsection is held downward at a 45-degree angle from the scalp before rolling.
  • Result: The roller sits completely off its base behind the bottom parting line. Produces minimum volume, allowing hair to lie smooth against the scalp.

Indentation and Finishing Techniques

• Indentation: The point where curls of opposite directions meet, forming a recessed, hollow area or valley in the wave pattern.
• Backcombing (Teasing / Ratting / Matting): Combing small sections of hair toward the scalp to form a cushion or base at the roots for volume and height.
• Backbrushing (Ruffing): Used to build a soft cushion and blend two or more curl patterns together for a smooth, seamless finish.

---

Thermal Styling: Marcel Irons & Flat Irons

Thermal styling uses heat tools to temporarily restructure the hair's hydrogen bonds, allowing straight hair to curl or curly hair to straighten.

Marcel Iron Manipulation

Conventional Marcel irons feature a smooth barrel (rod) and a concave shell clamp operated manually by the cosmetologist's fingers, rather than a spring-loaded thumb clamp.

• Hand Position: The handle of the shell rests between the thumb and fingers, allowing the stylist to roll the iron smoothly using finger movements.
• Fishhook Prevention: When winding hair around a thermal iron barrel, ends must be kept smooth and completely turned into the clamp. Leaving ends sticking out or turned backward creates unsightly crimped ends known as fishhooks.

Crucial Safety Standard: Testing Thermal Iron Temperature

Thermal irons and pressing combs reaching temperatures over 300°F to 400°F pose serious burning risks to client hair and scalp.

• Mandatory Testing Procedure: Before touching a heated Marcel iron or pressing comb to client hair, clamp the heated iron on a piece of white tissue paper or a white towel for 5 seconds.
• Interpretation: If the paper turns yellow, scorches, or turns brown, the iron is dangerously hot and will burn, discolor, or break the hair. Allow the iron to cool before use. White or gray hair is particularly sensitive to heat yellowing.

Flat Irons

Flat irons consist of two smooth heated plates (ceramic, tourmaline, or titanium). Passing flat irons smoothly over dry hair sections seals the cuticle, smooths frizzy textures, and aligns hydrogen bonds.

---

Hair Pressing Techniques & Thermal Protection

Hair pressing (historically called silking) is a temporary service that straightens extremely curly or resistant hair using a heated metal pressing comb.

The Three Hair Pressing Classifications

1. Soft Press: Removes 50% to 60% of the curl. Executed by applying a heated thermal pressing comb once on each side of the hair section with light pressure.
2. Medium Press: Removes 60% to 75% of the curl. Executed by applying a heated thermal pressing comb once on each side of the hair section with slightly increased pressure.
3. Hard Press (Double Press): Removes 100% of the curl. Executed by applying a heated thermal pressing comb twice on each side of the hair section. A hard press can also be accomplished by passing a flat iron after a soft comb press.

Hair Pressing Safety & Scalp Analysis

• Scalp Inspection: Never perform a hair pressing service on a client with scalp abrasions, open sores, contagious skin conditions, or severe burn scars.
• Elasticity Check: Check hair elasticity; damaged hair with low elasticity will break under the high heat of pressing combs.
• Comb Maintenance: Keep pressing combs clean. Burnt oils and carbon buildup on brass combs must be cleaned with a fine steel wool pad or baking soda solution.

Thermal Heat Protection Products

Prior to any thermal styling service (blow drying, flat ironing, or Marcel curling), a thermal heat protection spray, cream, or serum must be applied to damp or dry hair. Thermal protectants coat the hair shaft, reducing direct heat transfer, sealing moisture inside the cortex, and preventing cuticle degradation.