# Great Highland Bagpipe Assembly Manual

## Shop Principle

Do not build the ornate final set first. Bagpipes are a pressure-coupled reed
system; a beautiful bore that cannot be tuned with the chosen reeds is scrap.
Retire reed, pressure, and leakage risk before committing expensive blackwood.

## Tools And Fixtures

- Lathe with chuck/collet support, tailstock drill chuck, live center, and
  steady rest for long sections.
- Step-drill set, long bits, reamers, bore gauges, and a purpose-made chanter
  taper reamer.
- V-block or indexed drill fixture for chanter tone holes.
- Manometer for bag pressure.
- Calipers, small bore gauges, tuner, tape, beeswax, waxed hemp, and leak-test
  solution.
- Reed-seat and tenon/socket gauges turned from stable offcuts.

## Phase 0 - Buy The Coupling Parts

1. Buy at least three commercial chanter reeds before finalizing the reed seat.
2. Buy a synthetic drone reed set.
3. Buy or borrow a synthetic zipper bag and a blowpipe valve.
4. Measure reed body/staple diameters and update `validation.csv`.

## Phase 1 - Prototype Chanter

1. Rough-turn the blank oversized and leave holding allowance at both ends.
2. Establish the bore datum from the reed seat end.
3. Step-drill conservatively, then ream to the planned taper.
4. Turn the exterior only after the bore is confirmed straight enough.
5. Drill tone holes undersize using the datum plan in `drawing-brief.md`.
6. Fit a commercial reed and check Low A at stable pressure.
7. Use tape and incremental enlargement to bring the scale into range.

## Phase 2 - Tenor Drone Proof

1. Build one tenor drone bottom and top.
2. Bore the bottom and top to the workbook dimensions.
3. Turn the tuning slide with planned hemp clearance.
4. Fit a tenor drone reed and find the slide range for A3.
5. Log reed setting, pressure, temperature, and cents error.
6. Duplicate the validated tenor.

## Phase 3 - Bass Drone

1. Build the bass bottom, middle, and top as separate sections.
2. Use a steady rest and center-drill strategy for the long middle section.
3. Bore slightly conservatively where reaming or sanding is planned.
4. Fit the bass drone reed and confirm A2 with usable tuning travel.

## Phase 4 - Stocks, Bag, And Blowpipe

1. Batch-turn five stocks with tie-in grooves.
2. Turn the blowpipe body and fit the one-way valve.
3. Tie the stocks into the synthetic bag.
4. Leak-test each stock before inserting reeds or drones.
5. Assemble all pipes with hemped joints and repeat the leak test.

## Phase 5 - Tuning And Balancing

1. Tune both tenors together at stable pressure.
2. Add the bass drone and tune it against the tenors.
3. Add the chanter and tune Low A against the drone reference.
4. Work upward through the chanter notes, changing one variable at a time.
5. If pressure changes shift multiple notes together, correct pressure/reed
   behavior before changing hole geometry.

## Maintenance Loop

- Before each session: inspect reeds, check hemped joints, confirm blowpipe
  valve seal, and run a short pressure hold.
- After each session: dry moisture from blowpipe and stocks, inspect reed
  seats, and loosen any joint that became too tight.
- Weekly during prototype: repeat drone tuning and bag leak validation.
- After 24 hours: recheck pitch because hemp compression can change slide
  position and air leakage.

## Stop Conditions

Stop and redesign or rebuild the affected part if any of these occur:

- Chanter bore wander is visible or pitch errors cannot be corrected with hole
  size/tape.
- A stock tie-in leaks after two attempts.
- A tuning slide binds before reaching target pitch.
- A reed only speaks outside the expected pressure range.
- Any crack appears around a bore, stock groove, or slide socket.