# Assembly Manual

## Scope

This manual covers the G4 PVC proof-of-tune body. Hardwood or bamboo bodies
should copy only the measured geometry from a successful PVC prototype.

## Steps

1. Measure the tube ID, OD, and straightness at three stations.
2. Cut the body 0.25 in long and square both ends.
3. Mark the head datum, window setback, and foot datum.
4. Cut a conservative rectangular window and leave the labium edge slightly
   heavy for hand finishing.
5. Fit a removable block so the windway is centered and airtight.
6. Shim or sand the windway toward the 0.040 in starter height.
7. Form the labium ramp to about 35 degrees and sharpen the edge.
8. Play first sound before drilling any finger holes.
9. Adjust window length and windway height until response is repeatable at low
   and medium breath pressure.
10. Drill tone holes undersize from the foot upward.
11. Tune by gradual enlargement, recording final diameters in `validation.csv`.
12. Trim the foot only after the scale is stable.
13. Photograph the block, window, labium, and final hole layout for the build
   log.

## Stop Conditions

- Stop if the block leaks enough to change response after reinstalling.
- Stop if the labium edge chips or tears; make a window coupon before recutting
  the body.
- Stop if the first tone requires high breath pressure only; fix voicing before
  drilling tone holes.