cnx_vinyl/docs/process-flow.md

# Production Process Flow: Audio File to Delivered Record

The complete chain with every check and approval gate. Three gates involve
the artist or label directly (marked as approval gates); everything else is
internal QC. Every step writes to the [traceability
database](traceability.md); the instruments behind the checks are specified
in [quality automation](quality-automation.md), the machines for stages 4
to 6 in [galvanics and stamper prep](equipment/galvanics.md) and the
[pressing line](equipment/pressing-line.md).

A printable diagram of this flow lives alongside this document:
[process-flow.drawio](process-flow.drawio) (editable),
[process-flow.png](process-flow.png), and
[process-flow.pdf](process-flow.pdf).

Orders reach stage 1 either directly or through the
[artist platform](artist-platform.md), where the upload, the automatic
audio and artwork checks and gate 1 happen before a fan-funded campaign
is allowed to go live.

```mermaid
flowchart TD
    A[1. Audio intake] --> G1{Artist gate:<br/>master plan approved}
    G1 --> B[2. Vinyl mastering]
    B --> G2{Artist gate:<br/>master approved}
    G2 --> C[3. Lathe cutting<br/>lacquer]
    C --> D[4. Silvering and<br/>electroforming<br/>father, mother, stampers]
    D --> E[5. Stamper prep<br/>punch, back-finish, coin]
    E --> F[6. Pressing]
    PVC[PVC compound intake] --> LAB[Material lab gate] --> F
    REG[Regrind stream] --> LAB
    LBL[Labels: print inspected,<br/>pre-dried in oven] --> F
    F --> G3{Artist gate:<br/>test pressing approved}
    G3 --> F2[Production run]
    F2 --> H[7. Finishing<br/>trim, sleeve, shrink]
    H --> I[8. Packaging<br/>and assembly]
    CART[Cartons and sleeves<br/>from local partners] --> PQC[Packaging incoming QC] --> I
    I --> J[9. Fulfillment<br/>warehouse, bulk, dropshipping]

    A -.-> QA1[Checksums, format,<br/>technical QA]
    C -.-> QA3[Groove microscope,<br/>test cut, dead-wax<br/>scribe and fiducial]
    D -.-> QA4[Bath logs, XRF thickness,<br/>metrology on sampled zones,<br/>mother listening check,<br/>laser back marks]
    E -.-> QA5[Concentricity,<br/>dimensional, visual]
    F2 -.-> QA6[Press telemetry per cycle,<br/>100% optical inspection,<br/>sampled audio comparison]
    I -.-> QA8[Matrix code vs jacket<br/>barcode scan, barcode<br/>verification]
```

## Stage by stage

| # | Stage | Internal checks | Approval gate |
|---|---|---|---|
| 1 | Audio intake | File checksums and format verification; technical QA (levels, clipping, side length vs format) | Artist/label confirms the master plan |
| 2 | Vinyl mastering | Engineer QA of the vinyl master | Artist/label approves the master |
| 3 | Lathe cutting | Groove inspection under microscope; test cut evaluation; dead-wax matrix scribe and angular fiducial applied (cold mechanical scribe, never laser) | |
| 4 | Silvering and electroforming | Bath chemistry logs per batch; XRF nickel thickness per part; confocal/profiler groove metrology on sampled radial zones; mother listening check (mothers are playable); laser Data Matrix marks on part backs | |
| 5 | Stamper prep | Concentricity and dimensional checks after punch, back-finish, and coining; visual inspection | |
| M | PVC intake (parallel input) | Material lab gate per lot: certificate of analysis, moisture, heat stability, color, density, granulate physicals; new lots released only by test pressing; regrind stream passes its own contamination gate before joining the 80/20 mix | |
| L | Labels (parallel input) | Print inspection of each label lot against the approved proof; labels pre-dried in the oven before they go to the press (moisture in the paper causes bubbles); label lot logged per press cycle | |
| 6 | Pressing | Bottom label, cake and top label are loaded between the stampers every cycle, so the labels are pressed into the record; press telemetry logged every cycle; then per record: 100% inline optical inspection (including label identity and centering); sampled automated audio comparison against the source master | Artist/label approves the test pressing before the production run |
| 7 | Finishing | Trimming quality; inner sleeving; shrink wrap on sampling basis | |
| 8 | Packaging | Incoming carton QC per delivery (dimensions, print Delta E against approved proof, seam strength, inner sleeve scuff check); assembly verification by scanning the runout matrix code against the jacket barcode; barcode verification on every unit | |
| 9 | Fulfillment | Consignment assembly against the order's bill of materials; carrier tracking recorded per shipment or per dropshipped end customer | |

## Reading the chain

- **The three artist gates** are the customer-facing milestones: master plan,
  approved master, approved test pressing. Nothing proceeds past a gate
  without a recorded approval, and the approvals live in the same
  traceability record as the physical process data.
- **Identity travels with the product**: the dead-wax scribe from stage 3
  propagates through every metal generation and appears on every pressed
  record, which is what lets stage 9 verify that the right record is in the
  right jacket.
- **Materials join the chain with their own gates**: PVC lots, regrind
  batches and label lots enter at pressing, cartons and sleeves at
  packaging, and their lot IDs attach to every record and order they touch.
- **A complaint resolves backwards**: any single record traces to its
  stamper, press, cycle, operator, compound lot, and packaging lot, and from
  the stamper back through mother and father to the lacquer and the approved
  master it came from.