Nut String Spacing Generator

What this tool is for

Compare equal-center and equal-edge-gap nut layouts from real string diameters. Geometry tools apply explicit models to named measurements. A coordinate or angle must still be checked against a physical drawing, real hardware, tolerances, and material behavior.

Use it when you can describe the current state and need a defensible next check. It is not a shortcut around inspection: preserve the starting state, change one variable, and verify the result under the same conditions.

Before you begin

Measure nut width and define whether outside margins reference string edges or centers. Enter installed string diameters in one unit and choose equal-center or equal-gap layout.

• Use a stable, tuned instrument unless the page specifically investigates tuning.
• Name the physical reference, unit, and test condition beside every important number.
• Keep the original measurements so any reversible change can be returned to baseline.

Input guide

Number of strings

provides a measured or counted input; confirm the allowed range and repeat the reading before relying on it.

Nut width

supplies a measured geometric quantity whose datum and resolution should be written down.

Outer reference

classifies an observed condition; choose “unknown” or “not tested” instead of guessing when available.

Outer margin / center offset

supplies a measured geometric quantity whose datum and resolution should be written down.

String diameters, comma separated

records the actual string dimensions or supported set rather than a visual estimate.

Spacing method

classifies an observed condition; choose “unknown” or “not tested” instead of guessing when available.

Input and display unit

sets the interpretation and display unit; do not mix units elsewhere in the same run.

Measured 50mm calibration bar (mm)

provides a measured or counted input; confirm the allowed range and repeat the reading before relying on it.

Allowed calibration error (mm)

provides a measured or counted input; confirm the allowed range and repeat the reading before relying on it.

Input labels describe evidence, not targets. A placeholder demonstrates format only; it is never a recommendation for a particular guitar.

How the result should be read

Compare both tables and verify outer-string clearance over fret bevels on the actual neck. Transfer center marks only after the physical margin definition is confirmed.

Read priorities from top to bottom, but stop as soon as new evidence contradicts an earlier assumption. Save or print the result ticket with the entered conditions so another person can reproduce the decision.

Method and logic

Equal-center divides outer-center spread evenly. Equal-gap subtracts string radii and distributes open space so adjacent edge gaps match despite mixed gauges.

The page keeps calculation and diagnostic claims deliberately bounded. Display rounding improves readability, while the underlying logic uses entered values; descriptive branches report relative tendencies and the evidence needed to confirm them.

Worked example

For six mixed gauges, equal-center produces identical center intervals but visibly tighter open space beside the heavy strings. Switching to equal-gap changes the center coordinates while preserving chosen outer references.

The example demonstrates reasoning, not a universal setup specification. Substitute real measurements and repeat the final test before accepting the next action.

Assumptions and limitations

No calculator supplies a universal edge margin, ergonomic preference, slot width, or safe cutting depth. Real gauges, fret bevel, player technique, and nut material matter.

Instrument design, service history, measurement error, and player technique can outweigh a calculator or checklist. Where manufacturer instructions exist for the exact hardware, use those instructions and record the revision consulted.

Safety and stop conditions

Stop for abnormal resistance, cracking, heat, odor, electrical sensation, moving wood or joints, a measurement that cannot be repeated, or any step that would remove material without a confirmed cause. Secure strings and stored mechanical energy before hardware work. Refer structural, fret-cutting, mains-powered, or uncertain repairs to a qualified technician.

Related workflow

• Bridge String Spacing Generator — Plan saddle centers and string-edge gaps within a measured bridge footprint.
• String Gauge Change Planner — Compare old and new gauges, scale, and tuning before a setup change.
• How to Measure String Spacing — Distinguish centers from edge gaps.

Open the related page that answers the next unresolved question; do not run every tool as if every system needs adjustment.