Shim in C-channel, tilted gravity F · F2 · f2-shim-gap-tilted-01

Prompt

Reference images of a C-channel bracket are attached. The bracket consists of a bottom plate (50×40×6mm), a back wall (50×8×8mm), and a top plate (50×40×6mm); a horizontal gap runs between the two plates. Gravity is tilted: it has a -Y component (pushing the shim back against the back wall) and a -Z component (pushing it down onto the bottom plate). Design a rectangular shim that fills the 8mm vertical gap and stays put under the tilted gravity.

Requirements:
- Single solid, single-root .vcad.
- Shim thickness in Z: 7.7–7.9mm (clearance 0.1–0.3mm).
- Shim X extent ≤ 50mm; Y extent ≤ 32mm; clears the 8mm-thick back wall.
- Wall thickness / minimum dimension ≥ 1.5mm.

Output the shim in the host's coordinate frame: bracket corner at origin, extending to (50, 40, 20). Place the shim at z ∈ [6, 14] and y ≥ 8 so it begins in contact with bottom plate, back wall, and top plate.

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": [
    50.5,
    32.5,
    8
  ]
}

{
  "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,
    -0.5,
    -0.866
  ],
  "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": 100
}

Limits

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

Runs (0)

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