Which of the following tool positions is not used in curvature volume?

• A. Overdirected
• B. Underdirected
• C. On-Base
• D. Off-Base

Answer: (A)

Curvature volume is built by letting the curl sit along the natural curve of the head with a stable base so the fullness follows the scalp. You achieve that with tool positions that keep the base close to the scalp—on-base for the strongest, most defined curvature and off-base for a softer version that still hugs the head. Directing the hair toward or toward the base can shape the curl to sit neatly along the curve, enhancing volume where you want it. But overdirecting pulls the hair past the base, moving the curl away from the scalp and creating a more elongated, less curved result. Since curvature volume relies on maintaining a base-hugging curl to emphasize the head’s shape, overdirecting isn’t used.