{ "schema": "lower-steering-section-validation-v1", "baseline_commit": "b49b556c", "scope": "Estimated exposed lower shaft and compact rack-entry geometry, not fitted diameter, alignment, load or clearance.", "source_groups": 24, "valid_positive_solids": 45, "changed_source_groups": [ "steering_lhd_pinion_housing_and_input_shaft_comparison", "steering_column_retained_axis_smooth_shaft", "steering_split_pinion_coupling_envelope", "steering_pinion_pinch_fixing_envelopes" ], "unchanged_source_groups": [ "steering_rack_hollow_case_comparison", "steering_plunger_top_cap_smooth_plug_and_hex_envelope", "steering_smooth_rack_bar_without_teeth", "steering_column_hollow_outer_sleeve_comparison", "steering_left_inner_joint_cup_comparison", "steering_left_smooth_ball_and_tie_rod_comparison", "steering_left_outer_socket_comparison", "steering_left_hollow_corrugated_bellows_comparison", "steering_left_bellows_clip_envelopes", "steering_left_formed_body_bracket_comparison", "steering_left_front_clamp_cap_comparison", "steering_left_mounting_screw_washer_envelopes", "steering_right_inner_joint_cup_comparison", "steering_right_smooth_ball_and_tie_rod_comparison", "steering_right_outer_socket_comparison", "steering_right_hollow_corrugated_bellows_comparison", "steering_right_bellows_clip_envelopes", "steering_right_formed_body_bracket_comparison", "steering_right_front_clamp_cap_comparison", "steering_right_mounting_screw_washer_envelopes" ], "axis_endpoints_nodes_and_layout_held": true, "hidden_upper_shaft_geometry_held": true, "exposed_reference_section_diameter_mm": 16, "shaft_and_coupling_connected_solids": true, "source_shaft_vs_stub_and_coupling_contact_mm3": 0, "source_mount_contacts_mm3": { "old_shaft__front_left_rubber_and_bonded_face_comparison": 7862.9859, "current_shaft__front_left_rubber_and_bonded_face_comparison": 2438.8804, "old_shaft__front_left_frame_bracket_comparison": 0.0, "current_shaft__front_left_frame_bracket_comparison": 0.0, "old_shaft__front_engine_plate_with_integral_bent_mounting_tabs_comparison": 1251.84911, "current_shaft__front_engine_plate_with_integral_bent_mounting_tabs_comparison": 252.7998 }, "held_source_sha256": { "column-assembly-reference.json": "9623ce3ae6acf20615282804cd955f1153d33a80a30a29415403a4a7fc14bf28", "column-assembly-reference.step": "7dd4b5d829af4de5c95abc65c1bac46a707c9b690ccbfd8afa276bc2c1bc6c24", "front-power-support-reference.json": "bf3a72a24bf7ae334c685c7aa5d6743881d73e49da21684af1bf70eb764b98b4", "front-power-support-reference.step": "33883196ea776d2e9a5ff2308abdc7ec6c5261e652a9ae6056a4425a5c43a46b", "midget-1500-measured-core.json": "3e2577e1688663a6ea3a985091fc8a35bea6d5054514cafac4562973c741cc9e", "midget-1500-measured-core.step": "05849788af49defc430885ffedac66589fea076e2c7581197aff29780fed0a39", "front-structure-reference.json": "e4d9a50449ef1d5e68d98949f675da258221a3953ab759821a6a62cf5e83553b", "front-structure-reference.step": "37d8dd6b43212f75f27f2996d5203070c8b15cc93909df30bd1ee7950bab5052", "front-footwell-reference.json": "9c392f41f7b9706c9f1f302a276a64837d43805ade367787c173b50c66e0e3e7", "front-footwell-reference.step": "f84bbdbb7ab418fc825bc04fbe0c862dcd9b2f80075e38c18efaf6ceeb4eb559", "wiper-drive-reference.json": "9f245660a81989cbea242c282fd87bf1d37dfe9f8f4d6e00b26e5b01f7c886de", "wiper-drive-reference.step": "acee3ac3725e1819177fecee8d5fbad3a9b336e47cd390ca71e2651606fed3b3" }, "section_reference": { "owner_photo": "IMG_7041", "owner_dimensions_applied": false, "evidence": "/cars/1975-mg-midget/cad/lower-steering-section-validation.json", "former_uniform_shaft_diameter_mm": 27.093333333333337, "estimated_exposed_shaft_diameter_mm": 16, "retained_hidden_upper_shaft_diameter_mm": 27.093333333333337, "estimated_input_stub_diameter_mm": 16, "estimated_connection_bore_mm": 16.8, "estimated_coupling_outer_diameter_mm": 28, "estimated_pinion_neck_outer_bore_mm": [ 34, 17.6 ], "axis_and_endpoints_held": true, "body_plane_step_is_construction": true, "basis": "IMG7041 shows a slender exposed shaft beside the PF53 canister; the existing77mm filter catalog comparison supplies only a rough image-proportion check, not a calibrated scale. Factory p137 separates the exposed lower shaft from the outer jacket and supports a compact clamped entry.16mm is a selected photo-layout estimate, not a factory specification, owner measurement, spline size or machining diameter.", "limits": "Projection depth, blur, occluded edges and actual diameter remain uncalibrated. Matching smooth input stub and coupling/neck envelopes are construction choices;0.4/0.8mm radial gaps are display allowances, not fitted clearances. Upper step location/diameter are unverified hidden geometry. No splines, telescoping/collapse mechanism, fitted clamp/shaft identity, thread engagement, strength, preload, alignment, safe support or removal path is established." }, "photo_observations": { "photo": "IMG_7041", "source_sha256": "bf546853ec20a178f8783ae1ccbc17cce487caac5226251af7dc1d227fdd59a5", "source_size_pixels": [ 5712, 4284 ], "exif_orientation": 3, "exif_orientation_applied_before_sampling": true, "working_size_pixels": [ 1800, 1350 ], "approximate_shaft_span_endpoints": [ [ [ 780, 654 ], [ 774, 703 ] ], [ [ 1010, 679 ], [ 1003, 731 ] ] ], "approximate_filter_span_endpoints": [ [ 940, 510 ], [ 1210, 510 ] ], "pf53_catalog_diameter_comparison_mm": 77, "catalog_source": "https://www.jegs.com/i/acdelco-065-pf53-engine-oil-filter-spin-on-canister", "uncalibrated_diameter_proxies_mm": [ 14.07844620198824, 14.963392458082337 ], "selected_reference_diameter_mm": 16, "limits": "Hand-picked blurred/occluded edges. Different object depths and orientations prevent direct pixel-to-mm calibration. These rough proxies motivate a slimmer source section; they are not owner measurements, statistical uncertainty bounds or proof of16mm fitted diameter. Upper body-plane step and matching entry envelopes remain construction hypotheses." }, "source_sha256": { "steering-rack-reference.json": "c6328a02c5996079686a63b7070e99da78d61c5c22f6501c986f41bc9e9ee937", "steering-rack-reference.step": "325554b52c77fa286dedf9326355ff93e375f8f7aa19da1558ff6e936ef35dab" }, "limits": "Projection depth, blur, occluded edges and actual diameter remain uncalibrated. Matching smooth input stub and coupling/neck envelopes are construction choices;0.4/0.8mm radial gaps are display allowances, not fitted clearances. Upper step location/diameter are unverified hidden geometry. No splines, telescoping/collapse mechanism, fitted clamp/shaft identity, thread engagement, strength, preload, alignment, safe support or removal path is established.", "browser_validation": { "displayedRackMeshes": 23, "finiteVertices": 64104, "heldSurroundingMeshSamples": 1545, "heldColumnAssemblyMeshSamples": 6, "sourceMappingPickingAndMetricPlacement": true, "allNativeSourceStatusesReady": 74, "productionColumnSelection": true, "productionReloadAll74ReadyWithoutHooks": true, "pageErrors": [], "three_study_images_loaded": true, "native_downloads": true, "mobile_overflow": false }, "source_internal_construction_contacts_mm3": { "left_formed_body_bracket_vs_pinion_housing": 113.0405, "left_front_clamp_cap_vs_pinion_housing": 77.5769, "left_mounting_screw_washer_vs_pinion_housing": 0.0, "left_inner_joint_cup_comparison_vs_smooth_ball_and_tie_rod_comparison": 0.0, "left_hollow_corrugated_bellows_comparison_vs_smooth_ball_and_tie_rod_comparison": 0.0, "right_formed_body_bracket_vs_pinion_housing": 0.0, "right_front_clamp_cap_vs_pinion_housing": 0.0, "right_mounting_screw_washer_vs_pinion_housing": 0.0, "right_inner_joint_cup_comparison_vs_smooth_ball_and_tie_rod_comparison": 0.0, "right_hollow_corrugated_bellows_comparison_vs_smooth_ball_and_tie_rod_comparison": 0.0 }, "documentary_gap": { "official_publication_listing": "https://store.otpubs.com/service-publications/", "listed_1975_north_america_manual": "AKM3267", "status": "Publication identified from the official catalog; relevant full steering alignment/removal text not read. No procedure is inferred from parts drawings or the UK mounting illustration." } }