Tube spacer for stepped shaft F · F1 · f1-spacer-shaft-01

Prompt

Reference images of a stepped shaft are attached. The shaft has two coaxial flanges separated by a narrower middle waist. Design a tube spacer that slides down over the waist from above and rests on the bottom flange's top face, filling the axial gap between the flanges.

Requirements:
- Single solid, single-root .vcad.
- The spacer's bore must clear the waist with 0.1–0.3mm radial clearance (so 20.2–20.6mm bore diameter for a 20mm waist).
- The spacer's outer diameter must not exceed the flange outer diameter.
- The spacer's length must fill the gap between the two flanges (≈30mm) without interfering with either flange.
- Wall thickness ≥ 1.5mm (printability).

Output the spacer in the host's coordinate frame: the shaft axis is +Z, the bottom face of the bottom flange sits at z = 0, the waist runs z = 10 to z = 40. Place the spacer in this same frame so the grader can assemble it directly with the host.

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

Anti-cheese

{
  "max_solid_count": 1,
  "min_accessory_volume_mm3": 100
}

Limits

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

Runs (0)

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