Wraps do two jobs. They create friction so the string can't slip through the post hole, and they set the angle the string takes over the nut. Plain strings are slick and thin, so they need more wraps to grip. Wound strings grip well and take up more room on the post, so they need fewer.
A simple way to measure slack on a guitar:
- Thread the string through the post hole and pull it snug.
- Pull back about one to two tuner-widths of slack (roughly two to three inches on a guitar).
- Bend the string sharply at the post hole and start winding.
- Guide each wrap so it sits below the one before it.
Signs you have the wrong amount:
- Wraps overlap or climb up the post: too much slack. Unwind and trim more.
- The string slips while tuning: too little slack, especially on plain strings.
- The string sits loose in the nut slot: not enough downward angle. Add a wrap so the string leaves the post lower.
Locking tuners need little or no wrapping, since a clamp holds the string. If you're changing gauges, buy what you need from our Electric Guitar Singles, Acoustic Guitar Singles or Bass Guitar Singles.