Axial gravity hold on a flanged shaft F · F2 · f2-collar-shaft-axial-01

Prompt

Reference images of a stepped shaft are attached. The shaft has two coaxial flanges separated by a narrower middle waist. Gravity acts downward along -Z, pulling a tube collar that slides over the waist toward the bottom flange. Design the collar so it sits on the waist between the flanges; the bottom flange should arrest its slide.

Requirements:
- Single solid, single-root .vcad.
- The collar's bore must clear the 20mm waist with 0.1–0.3mm radial clearance.
- The collar's outer diameter must not exceed the flange OD (40mm).
- The collar's length must be 25–30mm (it sits in the 30mm gap, gravity rests it on the bottom flange).
- Wall thickness ≥ 1.5mm.

Output the collar in the host's coordinate frame: shaft axis +Z, bottom flange's bottom face at z = 0, waist runs z = 10 to z = 40. Place the collar centred over the waist so it starts in contact with (or just above) the bottom flange.

Checks

{
  "type": "valid_solid"
}

{
  "type": "interference_volume",
  "host": "host_geometry",
  "max_mm3": 1
}

{
  "type": "contact_area",
  "host": "host_geometry",
  "epsilon_mm": 0.4,
  "min_mm2": 800
}

{
  "type": "envelope",
  "max_mm": [
    40.5,
    40.5,
    30.5
  ]
}

{
  "type": "mate_clearance",
  "host": "host_geometry",
  "min_mm": 0,
  "max_mm": 0.6
}

{
  "type": "gravity_hold",
  "host": "host_geometry",
  "host_mass_kg": 1,
  "gravity_dir": [
    0,
    0,
    -1
  ],
  "duration_sec": 0.5,
  "max_drift_mm": 50
}

{
  "type": "dfm",
  "rules": [
    "min_wall_1.5mm",
    "no_undercut"
  ]
}

Anti-cheese

{
  "max_solid_count": 1,
  "min_accessory_volume_mm3": 200
}

Limits

{
  "max_tokens": 60000,
  "max_wallclock_sec": 240,
  "max_tool_calls": 60
}

Runs (0)

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