D Kurd Handpan Root-Mode Prototype

Private research build packet | Source: handpan-design-table.xlsx

Final tuning is empirical. Formulas in this packet are first-order sanity checks, not final pitch predictions.

Root Specifications

ParameterValue
ScaleD Kurd
NotesD3, A3, Bb3, C4, D4, E4, F4, G4, A4
Shell21 in diameter, 9.5 in height, 1.0 mm steel
Gu3.5 in nominal port with measured final lip/edge
Material pathNitrided DC04 preferred; stainless is a separate measured branch

Build Sequence

  1. Inspect shells and record material, thickness map, mass, diameter, height, and rim condition.
  2. Prepare Gu edge and verify safe finish.
  3. Build tuning support ring and removable layout templates.
  4. Rough-form Ding and tone fields on a supported shell.
  5. Tune fundamentals, octaves, and compound fifths with FFT evidence.
  6. Rest, remeasure, and retune before shell closure.
  7. Bond shells after coupon testing and dry fit.
  8. Final tune through Gu; repeat one-week rest and retune cycles.

Release Gate

Keep private until a human handpan tuner and metal-forming reviewer approve the measured prototype data and process assumptions.