{
  "scope": "External supplier-photo comparison and source preservation only; not fitted dimensions, working internal fit or actual clearance.",
  "baseline_commit": "e89a2ec9",
  "source_groups": 9,
  "held_meshes": [
    "differential_pinion_flange_reference",
    "differential_pinion_seal_reference",
    "differential_left_side_gear_boundary_reference",
    "differential_right_side_gear_boundary_reference"
  ],
  "historical_carrier_unchanged_shape": true,
  "outer_tube_regions_held": true,
  "axle_pose_and_joint_planes_held": true,
  "shared_eight_comparison_bores_open": true,
  "axle_and_carrier_mouths_open": true,
  "joint_gasket_no_positive_overlap": true,
  "mesh_native_relative_volume_errors": {
    "rear_axle_housing_reference": 0.002924904183799759,
    "differential_carrier_gasket_reference": 0.0009367354438937214,
    "differential_carrier_reference": 0.0027005168397847834,
    "differential_historical_large_carrier_and_saddles_comparison": 0.002160803520408927,
    "differential_carrier_fixings_reference": 0.0009375089272547488,
    "differential_pinion_flange_reference": 0.0009316183485181817,
    "differential_pinion_seal_reference": 0.0009254312667538178,
    "differential_left_side_gear_boundary_reference": 0.0009309475189199778,
    "differential_right_side_gear_boundary_reference": 0.0009309475189199778
  },
  "internal_source_contacts_mm3": {
    "differential_open_cage_end_walls_bored_mount_and_hollow_journals": {
      "new_housing_mm3": 0.0,
      "new_carrier_mm3": 0.0
    },
    "differential_toothless_crown_wheel_boundary_without_ratio": {
      "new_housing_mm3": 32550.329340304525,
      "new_carrier_mm3": 12720.966109926472
    },
    "differential_left_independent_angular_contact_bearing_boundary": {
      "new_housing_mm3": 0.0,
      "new_carrier_mm3": 0.0
    },
    "differential_right_independent_angular_contact_bearing_boundary": {
      "new_housing_mm3": 0.0,
      "new_carrier_mm3": 0.0
    }
  },
  "comparison": {
    "classification": "Supplier-photo-ruler comparison and estimated external casing; no owner dimensions.",
    "factory_sources": [
      "https://www.spridgets.de/downloads/Parts-1977.pdf#page=146",
      "https://www.spridgets.de/downloads/Parts-1977.pdf#page=147"
    ],
    "comparison_source": "https://classiccarparts.co.nz/Morris-Minor-Parts/gasket-differential-case-flange-gasket.-mg-midget%2C-morris-minor-and-austin-healey-sprite.-dif107-2a7027?limit=100&order=ASC&sort=rating",
    "comparison_images": [
      "https://classiccarparts.co.nz/image/cache/catalog/products_2020/2A7027__1_-1000x1000.jpg",
      "https://classiccarparts.co.nz/image/cache/catalog/products_2020/2A7027__2_-1000x1000.jpg"
    ],
    "photo_ruler_observations": [
      {
        "image": 1,
        "metric_marks_mm": [
          50,
          200
        ],
        "source_pixels": [
          [
            326,
            579
          ],
          [
            903,
            417
          ]
        ],
        "approx_outer_image_bounds_xy": [
          [
            110,
            84
          ],
          [
            910,
            910
          ]
        ],
        "limitations": "Oblique ruler and gasket, hand-held edge, perspective and ruler/part coplanarity uncertain."
      },
      {
        "image": 2,
        "metric_marks_mm": [
          10,
          50
        ],
        "source_pixels": [
          [
            829,
            236
          ],
          [
            969,
            237
          ]
        ],
        "approx_outer_image_bounds_xy": [
          [
            128,
            120
          ],
          [
            875,
            838
          ]
        ],
        "limitations": "Short ruler span gives weaker scale; gasket/scale planes and perspective uncertain."
      }
    ],
    "interpretation": "Outer-span estimates are approximately200\u2013215mm across the two photographs. These are broad comparison estimates, not measured replacement dimensions. The former340mm gasket/carrier diameter is substantially larger than both comparisons.",
    "selected_reference_mm": {
      "gasket_outer_diameter": 210,
      "gasket_inner_diameter": 175,
      "estimated_fixing_pcd": 188,
      "hole_diameter_comparison": 8.4,
      "bowl_radial_radius": 118,
      "bowl_axial_radius": 110,
      "inner_bowl_radial_radius": 112,
      "inner_bowl_axial_radius": 104,
      "front_bowl_cut_z": 65,
      "gasket_rear_z": 83,
      "gasket_thickness": 0.5,
      "carrier_rear_z": 83.5,
      "carrier_thickness": 8,
      "carrier_cone_outer_radii": [
        95,
        45
      ],
      "carrier_cone_z": [
        91.5,
        250
      ]
    },
    "retained": "Axle center/body pose, tube-end planes, tube and halfshaft passages, rebound pins, hub/drum/wheel/track references, gasket/carrier axial joint planes, pinion bearing pockets, flange/seal source geometry and propshaft mating plane. Independent internal comparisons keep their dimensions and stations.",
    "historical_comparison": "Complete old large carrier with its saddles/arms/web is separately selectable and hidden until selected. It is retained at its original size/pose, not scaled into the new shell. The old260mm crown-wheel envelope is also an optional unfit comparison; its size remains unchanged and source conflicts are recorded.",
    "limits": "No fitted axle identity, actual casing/gasket dimensions, loaded shape, crown-wheel diameter/ratio, gear mesh, wall gauge, stud thread, clocking, bearing support/preload, sealing, operating clearance or removal path is established. Bowl shape/depth/walls, flange bore/PCD, conical carrier, four rib sections and transitions remain estimates. Internal bearing/cage/crown/pinion comparisons are not validated by the new outer shell; contacts are source conflicts, not actual-car interferences. No internal part or surrounding obstacle is moved or reduced to erase contacts. Factory parts roles are distinct from the supplier ruler interpretation and from the actual car."
  },
  "source_sha256": {
    "rear-axle-reference.step": "b50bb0e40ebed8a6ec4cf05ccdfe63b2f32ab890dbaecb35de4d072dd678e857",
    "rear-axle-reference.json": "27c1c2b43d021f8a595a2f4a79ec938bb346580fe8591ef240e8cd27f42c728a",
    "differential-support-reference.json": "3244b5bcbcb76eecf8fec242d027b349ee645b11145857b8a5fe6959103cbbc7",
    "differential-support-reference.step": "a88bbefd7931d0b0faab35ac1824548d59ad1a5b12c59a23dac23ae9d4067816"
  }
}