# Handpan Assembly Manual

## Build Status

This manual is for a first D Kurd handpan prototype. It assumes purchased or professionally formed shells. First-time hand sinking is treated as a separate training project because shell geometry and thickness consistency are central to tuning repeatability.

## Tools And Setup

- Stable tuning stand or support ring.
- Smooth-faced tuning hammers, rubber or nylon mallet, and dimple tooling.
- Calipers, micrometer, flexible tape, radius gauges, and layout templates.
- Calibrated microphone or consistent recording setup, strobe tuner, and FFT/spectrogram software.
- Deburring tools, non-marring clamps, adhesive applicator, PPE, hearing protection, eye protection, gloves, and ventilation.

## Phase 1 - Incoming Inspection

1. Photograph both shells from top, side, inside, rim, and Gu area.
2. Record shell diameter, height, rim roundness, mass, and thickness map.
3. Inspect for cracks, wrinkles, hard creases, oil-canning, corrosion, and sharp rim defects.
4. Reject or branch the packet if shell thickness, material, or geometry differs materially from the design assumptions.

## Phase 2 - Gu Port

1. If the bottom shell is not pre-cut, mark the Gu center from the shell datum.
2. Cut a 3.5 in nominal port only with the shell supported.
3. Deburr both sides fully.
4. Roll, trim, or protect the port edge so it cannot cut the player.
5. Measure actual diameter and lip depth; enter these into the workbook and Wolfram model.

## Phase 3 - Layout

1. Establish a centerline and clock reference on the top shell.
2. Mark the Ding center and eight surrounding tone fields using removable templates.
3. Use the workbook clock positions as layout references, then adjust for real shell curvature and hand clearance.
4. Mark each field name, note, target fundamental, octave, and compound fifth on low-tack tape.

## Phase 4 - Rough Forming

1. Practice on scrap or a rejected shell before touching the real top shell.
2. Raise or form the Ding first, leaving final pitch margin.
3. Form each surrounding field dimple and shoulder gradually.
4. Avoid sharp dents, creases, or localized thinning.
5. Stop frequently to measure pitch tendencies and visible deformation.

## Phase 5 - Top Shell Tuning

1. Tune Ding D3 first.
2. Tune surrounding fields from low to high: A3, Bb3, C4, D4, E4, F4, G4, A4.
3. For every field, measure fundamental, octave, and compound fifth.
4. After adjusting any field, remeasure all previously tuned fields.
5. Keep a tuning log with hammer location, hammer type, strike force estimate, measured cents change, and comments.
6. Do not chase final cents before the shell has rested; rough stability matters first.

## Phase 6 - Rest And Drift Check

1. Let the tuned top shell rest for at least 24 hours.
2. Remeasure every field and partial under the same microphone setup.
3. If any field drifts more than 15 cents, continue top-shell tuning before assembly.
4. Repeat until the top shell is stable enough to justify closure.

## Phase 7 - Shell Closure

1. Dry-fit the shells and mark rim alignment.
2. Confirm Gu access allows final tuning reach.
3. Perform adhesive coupon testing before final closure.
4. Apply a continuous, controlled bead of approved flexible adhesive.
5. Clamp evenly without distorting the rim.
6. Cure according to adhesive data sheet and shop temperature.

## Phase 8 - Final Tuning

1. After cure, remeasure all 27 partial targets.
2. Tune through the Gu using small increments.
3. Record cross-talk matrix and sustain data.
4. Let the assembled pan rest one to two weeks.
5. Repeat remeasure and retune cycles until drift meets the acceptance target.

## Phase 9 - Finish And Storage

1. Remove residue without abrasive damage.
2. Protect nitrided steel with compatible oil, or clean stainless according to supplier guidance.
3. Install safe Gu edge trim if used.
4. Store in a padded case away from temperature shock and impacts.

## Stop Conditions

Stop and review with a human tuner or metal-forming lead if the shell cracks, buckles, rings with persistent buzzes, shows uncontrolled drift, develops sharp creases, or cannot hold the 1:2:3 partial relationship after multiple measured passes.