Spacer on shaft, sideways gravity F · F2 · f2-spacer-shaft-sideways-01

Prompt

Reference images of a stepped shaft are attached. The shaft has two coaxial flanges separated by a 20mm-diameter, 30mm-long waist. Design a tube spacer that fills the gap between flanges. Gravity acts sideways (along -Y, perpendicular to the shaft axis), pushing the spacer laterally; the waist must keep it from translating off the shaft.

Requirements:
- Single solid, single-root .vcad.
- Bore clears the 20mm waist with 0.1–0.3mm radial clearance.
- Outer diameter ≤ 40mm.
- Length 29.5–30mm (fills the axial gap, with the flanges arresting any axial motion).
- Wall thickness ≥ 1.5mm.

Output in host's frame: shaft axis +Z, bottom flange bottom face at z = 0, waist z = 10 to z = 40. Place spacer coaxial, z ∈ [10, 40].

Checks

{
  "type": "valid_solid"
}

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

{
  "type": "contact_area",
  "host": "host_geometry",
  "epsilon_mm": 0.3,
  "min_mm2": 1500
}

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

{
  "type": "mate_clearance",
  "host": "host_geometry",
  "min_mm": 0,
  "max_mm": 0.5
}

{
  "type": "gravity_hold",
  "host": "host_geometry",
  "host_mass_kg": 0.5,
  "gravity_dir": [
    0,
    -1,
    0
  ],
  "duration_sec": 0.5,
  "max_drift_mm": 2000
}

{
  "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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