# Product Pass · Booth NFC Stands

3D-printable holders for the Amazon **NTAG215 CR80** NFC cards
([listing](https://www.amazon.com/dp/B0FF9D3TBF)) used at each product roadshow booth.

## Card dimensions

| | mm | inches |
|---|---|---|
| Width | 85.5 | 3.36 |
| Height | 54.0 | 2.12 |
| Thickness | 0.86 | 0.03 |

Slot clearance in these models: **86.1 × 54.5 × 1.2 mm** (FDM slide fit).

## Designs

| File | Style | How the card embeds | Best for |
|---|---|---|---|
| `01-booth-tent.stl` | Angled L-tent | Slides in from the **top** behind a thin front wall | Table-height booth presence |
| `02-desk-wedge.stl` | Low desk wedge | Slides in from the **side** under the slope | Low-profile / less visual bulk |
| `03-flat-tap-mat.stl` | Flat plaque | Slides in from the **short edge** | Discrete tap target + QR sticker on top |
| `04-pause-embed-plaque.stl` | Sealed plaque | **Pause mid-print**, drop card in, resume | Permanent embed, no removable card |

No glue, tape, or magnets — friction slot or sealed cavity.

## Print settings (starting point)

- **Material:** PLA or PETG (avoid metal-fill near the antenna)
- **Layer height:** 0.2 mm
- **Infill:** 20–30%
- **Walls:** ≥3 perimeters
- **Supports:** none for wedge / flat mats; tent may want a brim
- **Orientation:**
  - Tent: on the base foot
  - Wedge / mats: flat on the bottom face
- Keep plastic over the chip **≤ ~1.2–1.5 mm** (already modeled) so phones can read through it

### Pause-embed (#04)

1. Slice and note the layer where the cavity floor finishes (notch on the edge marks height).
2. Print → pause → drop CR80 card into the cavity (antenna side up toward tap face).
3. Resume. Card is sealed inside.

## Program the cards

Each booth card should open that station’s URL, e.g.  
`https://pass.example.com/booth/ascend`  
Use any NFC writer app (iOS Shortcuts / NFC Tools / TagWriter). Lock after testing if you want them read-only.

## Regenerate

```bash
python3 stands/src/generate_stands.py
```

Requires: `trimesh`, `manifold3d`, `numpy`.