diff --git a/crates/engine/src/tests.rs b/crates/engine/src/tests.rs
index c43b2a14..2ad0dbe8 100644
--- a/crates/engine/src/tests.rs
+++ b/crates/engine/src/tests.rs
@@ -283,6 +283,7 @@ mod loft_spacing;
 mod mirror_planes;
 mod path_scope;
 mod primitive_points;
+mod rim_cut;
 mod robustness;
 mod robustness_goldens;
 mod spiral_join;
diff --git a/crates/engine/src/tests/fixtures/battery-tpu-case.solidcraft b/crates/engine/src/tests/fixtures/battery-tpu-case.solidcraft
new file mode 100644
index 00000000..1d5902c0
--- /dev/null
+++ b/crates/engine/src/tests/fixtures/battery-tpu-case.solidcraft
@@ -0,0 +1,1484 @@
+{
+  "format": "solidcraft/18",
+  "name": "Battery TPU Case",
+  "units": "mm",
+  "params": [
+    {
+      "name": "batt_w",
+      "expr": "290 mm",
+      "unit": "mm",
+      "comment": "Battery flat top/bottom width",
+      "model": false
+    },
+    {
+      "name": "batt_bulge",
+      "expr": "10 mm",
+      "unit": "mm",
+      "comment": "Side bulge past the top/bottom corners",
+      "model": false
+    },
+    {
+      "name": "batt_h",
+      "expr": "92 mm",
+      "unit": "mm",
+      "comment": "Battery height",
+      "model": false
+    },
+    {
+      "name": "peak_left",
+      "expr": "27 mm",
+      "unit": "mm",
+      "comment": "Height of the left side's widest point",
+      "model": false
+    },
+    {
+      "name": "peak_right",
+      "expr": "batt_h - peak_left",
+      "unit": "mm",
+      "comment": "Height of the right side's widest point",
+      "model": false
+    },
+    {
+      "name": "batt_len",
+      "expr": "198 mm",
+      "unit": "mm",
+      "comment": "Battery length",
+      "model": false
+    },
+    {
+      "name": "tab_w",
+      "expr": "15 mm",
+      "unit": "mm",
+      "comment": "Connector tab width (from the left top corner)",
+      "model": false
+    },
+    {
+      "name": "tab_depth",
+      "expr": "5.5 mm",
+      "unit": "mm",
+      "comment": "Connector tab protrusion",
+      "model": false
+    },
+    {
+      "name": "ramp_len",
+      "expr": "35 mm",
+      "unit": "mm",
+      "comment": "Ramp from tab back to the wall",
+      "model": false
+    },
+    {
+      "name": "ramp_blend_wall",
+      "expr": "80 mm",
+      "unit": "mm",
+      "comment": "Blend radius ramp to wall",
+      "model": false
+    },
+    {
+      "name": "ramp_blend_tab",
+      "expr": "40 mm",
+      "unit": "mm",
+      "comment": "Blend radius tab to ramp",
+      "model": false
+    },
+    {
+      "name": "wall",
+      "expr": "3 mm",
+      "unit": "mm",
+      "comment": "TPU wall thickness",
+      "model": false
+    },
+    {
+      "name": "r_big",
+      "expr": "5 mm",
+      "unit": "mm",
+      "comment": "Fillet on the 4 long profile edges (inside and outside)",
+      "model": false
+    },
+    {
+      "name": "r_small",
+      "expr": "1 mm",
+      "unit": "mm",
+      "comment": "Fillet on all other edges (inside and outside)",
+      "model": false
+    },
+    {
+      "name": "pleat_depth",
+      "expr": "10 mm",
+      "unit": "mm",
+      "comment": "Accordion pleat depth at the open edge",
+      "model": false
+    },
+    {
+      "name": "pleat_pitch",
+      "expr": "16 mm",
+      "unit": "mm",
+      "comment": "Accordion fold pitch",
+      "model": false
+    },
+    {
+      "name": "clear",
+      "expr": "1 mm",
+      "unit": "mm",
+      "comment": "Overshoot so trimming tools never sit on a face",
+      "model": false
+    },
+    {
+      "name": "d1",
+      "expr": "batt_w",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d2",
+      "expr": "batt_w",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d3",
+      "expr": "batt_h",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d4",
+      "expr": "batt_bulge",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d5",
+      "expr": "peak_right",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d6",
+      "expr": "batt_bulge",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d7",
+      "expr": "peak_left",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d10",
+      "expr": "batt_w + 2 * batt_bulge + 10 * clear",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d11",
+      "expr": "clear",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d12",
+      "expr": "batt_len",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d13",
+      "expr": "batt_len + tab_depth",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d14",
+      "expr": "batt_w / 2 - tab_w",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d15",
+      "expr": "ramp_len",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d16",
+      "expr": "ramp_blend_wall",
+      "unit": "mm",
+      "model": true
+    },
+    {
+      "name": "d17",
+      "expr": "ramp_blend_tab",
+      "unit": "mm",
+      "model": true
+    }
+  ],
+  "features": [
+    {
+      "id": 1,
+      "name": "BatteryProfile",
+      "suppressed": false,
+      "type": "sketch",
+      "plane": {
+        "type": "custom",
+        "plane": {
+          "origin": [
+            0.0,
+            0.0,
+            0.0
+          ],
+          "x_dir": [
+            1.0,
+            0.0,
+            0.0
+          ],
+          "y_dir": [
+            -0.0,
+            0.0,
+            1.0
+          ]
+        }
+      },
+      "sketch": {
+        "points": [
+          {
+            "id": "origin",
+            "pos": [
+              0.0,
+              0.0
+            ],
+            "fixed": true
+          },
+          {
+            "id": "l1.start",
+            "pos": [
+              -145.0,
+              92.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l1.end",
+            "pos": [
+              145.0,
+              92.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l2.end",
+            "pos": [
+              155.0,
+              65.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l3.end",
+            "pos": [
+              145.0,
+              0.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l4.end",
+            "pos": [
+              -145.0,
+              0.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l5.end",
+            "pos": [
+              -155.0,
+              27.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "p1",
+            "pos": [
+              -100.0,
+              0.0
+            ],
+            "fixed": true,
+            "link": "j1"
+          },
+          {
+            "id": "p2",
+            "pos": [
+              100.0,
+              0.0
+            ],
+            "fixed": true,
+            "link": "j1"
+          },
+          {
+            "id": "p3",
+            "pos": [
+              0.0,
+              -100.0
+            ],
+            "fixed": true,
+            "link": "j2"
+          },
+          {
+            "id": "p4",
+            "pos": [
+              0.0,
+              100.0
+            ],
+            "fixed": true,
+            "link": "j2"
+          }
+        ],
+        "curves": [
+          {
+            "id": "l1",
+            "type": "line",
+            "a": 1,
+            "b": 2,
+            "construction": false
+          },
+          {
+            "id": "l2",
+            "type": "line",
+            "a": 2,
+            "b": 3,
+            "construction": false
+          },
+          {
+            "id": "l3",
+            "type": "line",
+            "a": 3,
+            "b": 4,
+            "construction": false
+          },
+          {
+            "id": "l4",
+            "type": "line",
+            "a": 4,
+            "b": 5,
+            "construction": false
+          },
+          {
+            "id": "l5",
+            "type": "line",
+            "a": 5,
+            "b": 6,
+            "construction": false
+          },
+          {
+            "id": "l6",
+            "type": "line",
+            "a": 6,
+            "b": 1,
+            "construction": false
+          },
+          {
+            "id": "l7",
+            "type": "line",
+            "a": 7,
+            "b": 8,
+            "construction": true,
+            "link": "j1"
+          },
+          {
+            "id": "l8",
+            "type": "line",
+            "a": 9,
+            "b": 10,
+            "construction": true,
+            "link": "j2"
+          }
+        ],
+        "constraints": [
+          {
+            "id": "k1",
+            "type": "horizontal",
+            "l": 0
+          },
+          {
+            "id": "k2",
+            "type": "horizontal",
+            "l": 3
+          },
+          {
+            "id": "k3",
+            "type": "collinear",
+            "a": 3,
+            "b": 6
+          },
+          {
+            "id": "k4",
+            "type": "symmetric",
+            "p": 1,
+            "q": 2,
+            "l": 7
+          },
+          {
+            "id": "k5",
+            "type": "symmetric",
+            "p": 4,
+            "q": 5,
+            "l": 7
+          },
+          {
+            "id": "k6",
+            "type": "length",
+            "l": 0,
+            "value": 290.0,
+            "param": "d1"
+          },
+          {
+            "id": "k7",
+            "type": "length",
+            "l": 3,
+            "value": 290.0,
+            "param": "d2"
+          },
+          {
+            "id": "k8",
+            "type": "distance_y",
+            "p": 1,
+            "q": 5,
+            "value": 92.0,
+            "param": "d3"
+          },
+          {
+            "id": "k9",
+            "type": "distance_x",
+            "p": 2,
+            "q": 3,
+            "value": 10.0,
+            "param": "d4"
+          },
+          {
+            "id": "k10",
+            "type": "distance_y",
+            "p": 4,
+            "q": 3,
+            "value": 65.0,
+            "param": "d5"
+          },
+          {
+            "id": "k11",
+            "type": "distance_x",
+            "p": 5,
+            "q": 6,
+            "value": 10.0,
+            "param": "d6"
+          },
+          {
+            "id": "k12",
+            "type": "distance_y",
+            "p": 5,
+            "q": 6,
+            "value": 27.0,
+            "param": "d7"
+          }
+        ],
+        "links": [
+          {
+            "id": "j1",
+            "kind": "project",
+            "source": {
+              "type": "sketch_axis",
+              "name": "x"
+            }
+          },
+          {
+            "id": "j2",
+            "kind": "project",
+            "source": {
+              "type": "sketch_axis",
+              "name": "y"
+            }
+          }
+        ],
+        "counters": {
+          "j": 2,
+          "k": 12,
+          "l": 8,
+          "p": 4
+        }
+      }
+    },
+    {
+      "id": 2,
+      "name": "BatteryStock",
+      "suppressed": false,
+      "body_names": [
+        "Battery"
+      ],
+      "param_names": [
+        "d8"
+      ],
+      "type": "extrude",
+      "sketch": 1,
+      "profiles": {
+        "type": "all"
+      },
+      "extent": {
+        "distance": "batt_len + tab_depth + clear",
+        "direction": "positive"
+      },
+      "operation": "new_body"
+    },
+    {
+      "id": 3,
+      "name": "PlanOutline",
+      "suppressed": false,
+      "param_names": [
+        "d9"
+      ],
+      "type": "sketch",
+      "plane": {
+        "type": "offset",
+        "base": {
+          "type": "origin",
+          "name": "XY"
+        },
+        "distance": "-clear"
+      },
+      "sketch": {
+        "points": [
+          {
+            "id": "origin",
+            "pos": [
+              0.0,
+              0.0
+            ],
+            "fixed": true
+          },
+          {
+            "id": "l1.start",
+            "pos": [
+              -160.0,
+              1.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l1.end",
+            "pos": [
+              160.0,
+              1.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l2.end",
+            "pos": [
+              160.0,
+              -198.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "corner1",
+            "pos": [
+              -95.0,
+              -198.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "corner2",
+            "pos": [
+              -130.0,
+              -203.5
+            ],
+            "fixed": false
+          },
+          {
+            "id": "l5.end",
+            "pos": [
+              -160.0,
+              -203.5
+            ],
+            "fixed": false
+          },
+          {
+            "id": "p1",
+            "pos": [
+              0.0,
+              -100.0
+            ],
+            "fixed": true,
+            "link": "j1"
+          },
+          {
+            "id": "p2",
+            "pos": [
+              0.0,
+              100.0
+            ],
+            "fixed": true,
+            "link": "j1"
+          },
+          {
+            "id": "p3",
+            "pos": [
+              -88.75261852925456,
+              -198.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "p4",
+            "pos": [
+              -101.17164524862525,
+              -198.96982996764112
+            ],
+            "fixed": false
+          },
+          {
+            "id": "a1.center",
+            "pos": [
+              -88.75261852925458,
+              -278.0
+            ],
+            "fixed": false
+          },
+          {
+            "id": "p5",
+            "pos": [
+              -126.91417737568737,
+              -203.01508501617946
+            ],
+            "fixed": false
+          },
+          {
+            "id": "p6",
+            "pos": [
+              -133.12369073537272,
+              -203.5
+            ],
+            "fixed": false
+          },
+          {
+            "id": "a2.center",
+            "pos": [
+              -133.12369073537272,
+              -163.5
+            ],
+            "fixed": false
+          }
+        ],
+        "curves": [
+          {
+            "id": "l1",
+            "type": "line",
+            "a": 1,
+            "b": 2,
+            "construction": false
+          },
+          {
+            "id": "l2",
+            "type": "line",
+            "a": 2,
+            "b": 3,
+            "construction": false
+          },
+          {
+            "id": "l3",
+            "type": "line",
+            "a": 3,
+            "b": 9,
+            "construction": false
+          },
+          {
+            "id": "l4",
+            "type": "line",
+            "a": 10,
+            "b": 12,
+            "construction": false
+          },
+          {
+            "id": "l5",
+            "type": "line",
+            "a": 13,
+            "b": 6,
+            "construction": false
+          },
+          {
+            "id": "l6",
+            "type": "line",
+            "a": 6,
+            "b": 1,
+            "construction": false
+          },
+          {
+            "id": "l7",
+            "type": "line",
+            "a": 7,
+            "b": 8,
+            "construction": true,
+            "link": "j1"
+          },
+          {
+            "id": "a1",
+            "type": "arc",
+            "c": 11,
+            "a": 9,
+            "b": 10,
+            "construction": false
+          },
+          {
+            "id": "a2",
+            "type": "arc",
+            "c": 14,
+            "a": 13,
+            "b": 12,
+            "construction": false
+          }
+        ],
+        "constraints": [
+          {
+            "id": "k1",
+            "type": "horizontal",
+            "l": 0
+          },
+          {
+            "id": "k2",
+            "type": "vertical",
+            "l": 1
+          },
+          {
+            "id": "k3",
+            "type": "horizontal",
+            "l": 2
+          },
+          {
+            "id": "k4",
+            "type": "horizontal",
+            "l": 4
+          },
+          {
+            "id": "k5",
+            "type": "vertical",
+            "l": 5
+          },
+          {
+            "id": "k6",
+            "type": "symmetric",
+            "p": 1,
+            "q": 2,
+            "l": 6
+          },
+          {
+            "id": "k7",
+            "type": "length",
+            "l": 0,
+            "value": 320.0,
+            "param": "d10"
+          },
+          {
+            "id": "k8",
+            "type": "distance_y",
+            "p": 0,
+            "q": 1,
+            "value": 1.0,
+            "param": "d11"
+          },
+          {
+            "id": "k9",
+            "type": "distance_y",
+            "p": 0,
+            "q": 3,
+            "value": 198.0,
+            "param": "d12"
+          },
+          {
+            "id": "k10",
+            "type": "distance_y",
+            "p": 0,
+            "q": 5,
+            "value": 203.5,
+            "param": "d13"
+          },
+          {
+            "id": "k11",
+            "type": "distance_x",
+            "p": 0,
+            "q": 5,
+            "value": 130.0,
+            "param": "d14"
+          },
+          {
+            "id": "k12",
+            "type": "distance_x",
+            "p": 5,
+            "q": 4,
+            "value": 35.0,
+            "param": "d15"
+          },
+          {
+            "id": "k13",
+            "type": "point_on_curve",
+            "p": 4,
+            "c": 2
+          },
+          {
+            "id": "k14",
+            "type": "point_on_curve",
+            "p": 4,
+            "c": 3
+          },
+          {
+            "id": "k15",
+            "type": "tangent",
+            "a": 2,
+            "b": 7
+          },
+          {
+            "id": "k16",
+            "type": "tangent",
+            "a": 3,
+            "b": 7
+          },
+          {
+            "id": "k17",
+            "type": "radius",
+            "c": 7,
+            "value": 80.0,
+            "param": "d16"
+          },
+          {
+            "id": "k18",
+            "type": "point_on_curve",
+            "p": 5,
+            "c": 3
+          },
+          {
+            "id": "k19",
+            "type": "point_on_curve",
+            "p": 5,
+            "c": 4
+          },
+          {
+            "id": "k20",
+            "type": "tangent",
+            "a": 3,
+            "b": 8
+          },
+          {
+            "id": "k21",
+            "type": "tangent",
+            "a": 4,
+            "b": 8
+          },
+          {
+            "id": "k22",
+            "type": "radius",
+            "c": 8,
+            "value": 40.0,
+            "param": "d17"
+          }
+        ],
+        "links": [
+          {
+            "id": "j1",
+            "kind": "project",
+            "source": {
+              "type": "sketch_axis",
+              "name": "y"
+            }
+          }
+        ],
+        "counters": {
+          "a": 2,
+          "corner": 2,
+          "j": 1,
+          "k": 22,
+          "l": 7,
+          "p": 6
+        }
+      }
+    },
+    {
+      "id": 4,
+      "name": "TabAndRamp",
+      "suppressed": false,
+      "param_names": [
+        "d18"
+      ],
+      "type": "extrude",
+      "sketch": 3,
+      "profiles": {
+        "type": "all"
+      },
+      "extent": {
+        "distance": "batt_h + 2 * clear",
+        "direction": "positive"
+      },
+      "operation": "intersect",
+      "targets": [
+        "Battery"
+      ]
+    },
+    {
+      "id": 5,
+      "name": "CopyForCase",
+      "suppressed": false,
+      "body_names": [
+        "Case"
+      ],
+      "param_names": [
+        "d19",
+        "d20",
+        "d21"
+      ],
+      "type": "move",
+      "bodies": [
+        "Battery"
+      ],
+      "translate": [
+        "0",
+        "0",
+        "0"
+      ],
+      "copy": true
+    },
+    {
+      "id": 6,
+      "name": "CaseShell",
+      "suppressed": false,
+      "param_names": [
+        "d22"
+      ],
+      "face_names": [
+        "F2:side:l4"
+      ],
+      "type": "shell",
+      "faces": [
+        [
+          0.0,
+          -100.0,
+          0.0
+        ]
+      ],
+      "thickness": "wall",
+      "body": "Case",
+      "direction": "outside"
+    },
+    {
+      "id": 7,
+      "name": "Fillet1",
+      "suppressed": false,
+      "param_names": [
+        "d23"
+      ],
+      "edge_refs": [
+        {
+          "dir": [
+            0.0,
+            -1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            -1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            -1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            -1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.0,
+            1.0,
+            0.0
+          ],
+          "min": [
+            -158.08338344416106,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            158.08338344416106,
+            3.0000000000000004,
+            95.0
+          ]
+        }
+      ],
+      "edge_names": [
+        "F2:side:l5@F5.1|F2:side:l6@F5.1",
+        "F2:side:l1@F5.1|F2:side:l6@F5.1",
+        "F2:side:l1@F5.1|F2:side:l2@F5.1",
+        "F2:side:l2@F5.1|F2:side:l3@F5.1",
+        "F6:inner:F2:side:l5@F5.1|F6:inner:F2:side:l6@F5.1",
+        "F6:inner:F2:side:l1@F5.1|F6:inner:F2:side:l6@F5.1",
+        "F6:inner:F2:side:l1@F5.1|F6:inner:F2:side:l2@F5.1",
+        "F6:inner:F2:side:l2@F5.1|F6:inner:F2:side:l3@F5.1"
+      ],
+      "type": "fillet",
+      "edges": [
+        [
+          -158.0834,
+          -101.75,
+          26.6874
+        ],
+        [
+          -147.5738,
+          -101.75,
+          95.0
+        ],
+        [
+          147.088,
+          -99.0,
+          95.0
+        ],
+        [
+          158.0834,
+          -99.0,
+          65.3126
+        ],
+        [
+          -155.0,
+          -101.75,
+          27.0
+        ],
+        [
+          -145.0,
+          -101.75,
+          92.0
+        ],
+        [
+          145.0,
+          -99.0,
+          92.0
+        ],
+        [
+          155.0,
+          -99.0,
+          65.0
+        ]
+      ],
+      "radius": "r_big",
+      "body": "Case"
+    },
+    {
+      "id": 8,
+      "name": "Fillet2",
+      "suppressed": false,
+      "param_names": [
+        "d24"
+      ],
+      "edge_refs": [
+        {
+          "dir": [
+            0.34731435582359377,
+            0.0,
+            -0.9377487607237037
+          ],
+          "min": [
+            -157.9189160095873,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            157.9189160095873,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            -0.1520571842539413,
+            6.854850442197856e-18,
+            -0.9883716976506173
+          ],
+          "min": [
+            -157.9189160095873,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            157.9189160095873,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            -0.3473143558235947,
+            0.0,
+            0.9377487607237034
+          ],
+          "min": [
+            -157.9189160095873,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            157.9189160095873,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.15205718425394107,
+            6.990187846251234e-18,
+            0.9883716976506172
+          ],
+          "min": [
+            -157.9189160095873,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            157.9189160095873,
+            3.0000000000000004,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            1.0,
+            -1.5479309295511088e-18,
+            0.0
+          ],
+          "min": [
+            -157.9189160095873,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            157.9189160095873,
+            3.0000000000000004,
+            95.0
+          ]
+        }
+      ],
+      "edge_names": [
+        "F2:side:l2@F5.1|F2:start@F5.1",
+        "F2:side:l3@F5.1|F2:start@F5.1",
+        "F2:side:l5@F5.1|F2:start@F5.1",
+        "F2:side:l6@F5.1|F2:start@F5.1",
+        "F2:side:l1@F5.1|F2:start@F5.1"
+      ],
+      "type": "fillet",
+      "edges": [
+        [
+          152.5857,
+          3.0,
+          80.1563
+        ],
+        [
+          153.0593,
+          3.0,
+          32.6563
+        ],
+        [
+          -153.1413,
+          3.0,
+          13.3437
+        ],
+        [
+          -152.8286,
+          3.0,
+          60.8437
+        ],
+        [
+          -0.2429,
+          3.0,
+          95.0
+        ]
+      ],
+      "radius": "r_small",
+      "body": "Case"
+    },
+    {
+      "id": 9,
+      "name": "Fillet3",
+      "suppressed": false,
+      "param_names": [
+        "d25"
+      ],
+      "edge_refs": [
+        {
+          "dir": [
+            -1.0,
+            -2.4685277687458984e-16,
+            0.0
+          ],
+          "min": [
+            -157.91891600958726,
+            -206.5,
+            -2.220446049250313e-16
+          ],
+          "max": [
+            157.91891600958732,
+            3.000000000000001,
+            95.0
+          ]
+        }
+      ],
+      "edge_names": [
+        "F6:inner:F2:side:l1@F5.1|F6:inner:F4:side:l3@F5.1"
+      ],
+      "type": "fillet",
+      "edges": [
+        [
+          26.3837,
+          -198.0,
+          92.0
+        ]
+      ],
+      "radius": "r_small",
+      "body": "Case"
+    },
+    {
+      "id": 10,
+      "name": "Fillet4",
+      "suppressed": false,
+      "param_names": [
+        "d26"
+      ],
+      "edge_refs": [
+        {
+          "dir": [
+            0.1520571842539411,
+            0.0,
+            0.988371697650617
+          ],
+          "min": [
+            -157.91891600958726,
+            -206.5,
+            -1.6689699017913788e-14
+          ],
+          "max": [
+            157.91891600958732,
+            3.000000000000001,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            -0.34731435582359377,
+            0.0,
+            0.9377487607237037
+          ],
+          "min": [
+            -157.91891600958726,
+            -206.5,
+            -1.6689699017913788e-14
+          ],
+          "max": [
+            157.91891600958732,
+            3.000000000000001,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            -1.0,
+            0.0,
+            0.0
+          ],
+          "min": [
+            -157.91891600958726,
+            -206.5,
+            -1.6689699017913788e-14
+          ],
+          "max": [
+            157.91891600958732,
+            3.000000000000001,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            -0.15205718425394102,
+            0.0,
+            -0.9883716976506172
+          ],
+          "min": [
+            -157.91891600958726,
+            -206.5,
+            -1.6689699017913788e-14
+          ],
+          "max": [
+            157.91891600958732,
+            3.000000000000001,
+            95.0
+          ]
+        },
+        {
+          "dir": [
+            0.3473143558235949,
+            0.0,
+            -0.9377487607237033
+          ],
+          "min": [
+            -157.91891600958726,
+            -206.5,
+            -1.6689699017913788e-14
+          ],
+          "max": [
+            157.91891600958732,
+            3.000000000000001,
+            95.0
+          ]
+        }
+      ],
+      "edge_names": [
+        "F6:inner:F2:side:l3@F5.1|F6:inner:F2:start@F5.1",
+        "F6:inner:F2:side:l2@F5.1|F6:inner:F2:start@F5.1",
+        "F6:inner:F2:side:l1@F5.1|F6:inner:F2:start@F5.1",
+        "F6:inner:F2:side:l6@F5.1|F6:inner:F2:start@F5.1",
+        "F6:inner:F2:side:l5@F5.1|F6:inner:F2:start@F5.1"
+      ],
+      "type": "fillet",
+      "edges": [
+        [
+          149.9014,
+          0.0,
+          31.8594
+        ],
+        [
+          150.3792,
+          0.0,
+          77.4761
+        ],
+        [
+          0.4048,
+          0.0,
+          92.0
+        ],
+        [
+          -150.2276,
+          0.0,
+          58.0208
+        ],
+        [
+          -149.7749,
+          0.0,
+          12.8922
+        ]
+      ],
+      "radius": "r_small",
+      "body": "Case"
+    }
+  ],
+  "next_id": 30,
+  "visibility": {
+    "hidden_bodies": [
+      "Repro"
+    ],
+    "hidden_occurrences": [],
+    "hidden_origin": [],
+    "hidden_sketches": [],
+    "shown_sketches": []
+  }
+}
\ No newline at end of file
diff --git a/crates/engine/src/tests/rim_cut.rs b/crates/engine/src/tests/rim_cut.rs
new file mode 100644
index 00000000..9de40f3a
--- /dev/null
+++ b/crates/engine/src/tests/rim_cut.rs
@@ -0,0 +1,57 @@
+//! #882: a cut through the open rim of a shelled case failed once an R1 round went on the outer
+//! loop of the other end face. One strip of that round (along a sloped side edge, far from the
+//! cut) was never meshed: its boundary was projected onto its surface starting from a corner
+//! that a search without a hint misses, so the face was dropped. Every boolean with the body
+//! then failed (truck's meshes both operands to classify faces), and the exact fallback refused
+//! it for the same face. The owner's design, `battery-tpu-case.solidcraft` (format 18).
+
+use std::path::Path;
+
+use serde_json::json;
+
+use super::run;
+use crate::Session;
+
+fn open_at(feature: &str) -> Session {
+    let path = Path::new(env!("CARGO_MANIFEST_DIR")).join("src/tests/fixtures/battery-tpu-case.solidcraft");
+    let mut s = Session::default();
+    run(&mut s, "doc.open", json!({"path": path.to_string_lossy()}));
+    run(&mut s, "timeline.roll_to", json!({"feature": feature}));
+    s
+}
+
+/// The window cut through the front wall and its rim, 48 × 4 × 50 from below the rim.
+fn cut_window(s: &mut Session) -> serde_json::Value {
+    run(s, "solid.box", json!({"corner": [-24, -0.5, -1], "length": 48, "width": 4, "height": 50, "operation": "cut", "targets": ["Case"]}))
+}
+
+/// Every face of the case after the round meshes (the strip had no triangles at any tolerance).
+#[test]
+fn every_face_of_the_rounded_case_meshes() {
+    let s = open_at("Fillet2");
+    let case = s.model.state().body("Case").map(|b| b.body.clone()).unwrap();
+    let faces = case.faces(0.05).unwrap();
+    assert_eq!(faces.len(), case.face_count());
+    let unmeshed: Vec<usize> = faces.iter().filter(|f| f.area <= 0.0).map(|f| f.index).collect();
+    assert!(unmeshed.is_empty(), "faces with no mesh: {unmeshed:?}");
+}
+
+/// The cut takes the same window after the round as before it (the round is 120 mm away), in one
+/// boolean with no retry.
+#[test]
+fn rim_cut_after_the_round_on_the_other_end() {
+    let mut before = open_at("Fillet1");
+    let mut after = open_at("Fillet2");
+    let faces = |s: &Session| s.model.state().body("Case").map(|b| b.body.face_count()).unwrap();
+    let (f1, f2) = (faces(&before), faces(&after));
+    cut_window(&mut before);
+    let id = cut_window(&mut after)["feature"].as_u64().unwrap();
+    let result = after.model.result(id).unwrap();
+    assert!(result.error.is_none() && result.warning.is_none(), "{result:?}");
+    assert!(result.boolean_diagnostics.events.is_empty(), "{:?}", result.boolean_diagnostics);
+    // The window's three faces (two sides and the top), at both points of the timeline.
+    assert_eq!(faces(&before), f1 + 3);
+    assert_eq!(faces(&after), f2 + 3);
+    let case = after.model.state().body("Case").map(|b| b.body.clone()).unwrap();
+    assert_eq!(case.shell_count(), 1);
+}
diff --git a/vendor/README.md b/vendor/README.md
index 0d30476d..e5e9c1a6 100644
--- a/vendor/README.md
+++ b/vendor/README.md
@@ -59,6 +59,13 @@ Changes:
   This prevents huge arbitrary pole parameters from corrupting trimmed meshes (#796),
   while retaining genuine extrapolation for unbounded planes. Work is bounded to four
   endpoint evaluations per projected point; no search or tessellation tolerance is relaxed.
+- `tessellation/triangulation.rs`: a boundary loop is projected onto its surface point by point,
+  each searched from the one before; the first has no hint. When that walk fails, it is tried
+  once more from the first point an unhinted search finds. An unhinted search can miss a point
+  that lies on the surface, such as the corner of a fillet strip on a surface extended past it,
+  and the face was then left unmeshed, which also failed every boolean with the body (#882). A
+  walk that succeeds is kept as it was: where a loop starts decides how it is laid out across a
+  periodic surface's seam.
 - `tessellation/triangulation.rs`: the inside test of a face's boundary skips loops whose
   parameter box is clear of the point (it tested every segment of every loop, so a face with
   hundreds of holes meshed in quadratic time).
diff --git a/vendor/truck-meshalgo/src/tessellation/triangulation.rs b/vendor/truck-meshalgo/src/tessellation/triangulation.rs
index c5cb86de..558d202a 100644
--- a/vendor/truck-meshalgo/src/tessellation/triangulation.rs
+++ b/vendor/truck-meshalgo/src/tessellation/triangulation.rs
@@ -411,43 +411,60 @@ impl PolyBoundaryPiece {
     ) -> Option<Self> {
         let (up, vp) = (surface.u_period(), surface.v_period());
         let (urange, vrange) = surface.try_range_tuple();
-        let mut bdry3d: Vec<Point3> = wire
+        let bdry3d: Vec<Point3> = wire
             .flat_map(|poly_edge| {
                 let n = poly_edge.len() - 1;
                 poly_edge.into_iter().take(n)
             })
             .collect();
-        bdry3d.push(bdry3d[0]);
-        let mut previous = None;
-        let mut vec = bdry3d
-            .into_iter()
-            .flat_map(|pt| {
-                let (mut u, mut v) = match sp(surface, pt, previous) {
-                    // SolidCraft: validate exact and nearest results alike, once per
-                    // boundary point, including the bounded provisional preview.
-                    Some(hint) => sane(surface, pt, hint),
-                    None => return vec![None],
-                };
-                if let (Some(up), Some((u0, _))) = (up, previous) {
-                    u = get_mindiff(u, u0, up);
-                }
-                if let (Some(vp), Some((_, v0))) = (vp, previous) {
-                    v = get_mindiff(v, v0, vp);
-                }
-                let res = (|| {
-                    if let Some((u0, v0)) = previous {
-                        if !u0.near(&u) && surface.uder(u0, v0).so_small() {
-                            return vec![Some(Point2::new(u, v0)), Some(Point2::new(u, v))];
-                        } else if !v0.near(&v) && surface.vder(u0, v0).so_small() {
-                            return vec![Some(Point2::new(u0, v)), Some(Point2::new(u, v))];
-                        }
+        let walk = |mut bdry3d: Vec<Point3>| -> Option<Vec<Point2>> {
+            bdry3d.push(bdry3d[0]);
+            let mut previous = None;
+            bdry3d
+                .into_iter()
+                .flat_map(|pt| {
+                    let (mut u, mut v) = match sp(surface, pt, previous) {
+                        // SolidCraft: validate exact and nearest results alike, once per
+                        // boundary point, including the bounded provisional preview.
+                        Some(hint) => sane(surface, pt, hint),
+                        None => return vec![None],
+                    };
+                    if let (Some(up), Some((u0, _))) = (up, previous) {
+                        u = get_mindiff(u, u0, up);
                     }
-                    vec![Some(Point2::new(u, v))]
-                })();
-                previous = Some((u, v));
-                res
-            })
-            .collect::<Option<Vec<Point2>>>()?;
+                    if let (Some(vp), Some((_, v0))) = (vp, previous) {
+                        v = get_mindiff(v, v0, vp);
+                    }
+                    let res = (|| {
+                        if let Some((u0, v0)) = previous {
+                            if !u0.near(&u) && surface.uder(u0, v0).so_small() {
+                                return vec![Some(Point2::new(u, v0)), Some(Point2::new(u, v))];
+                            } else if !v0.near(&v) && surface.vder(u0, v0).so_small() {
+                                return vec![Some(Point2::new(u0, v)), Some(Point2::new(u, v))];
+                            }
+                        }
+                        vec![Some(Point2::new(u, v))]
+                    })();
+                    previous = Some((u, v));
+                    res
+                })
+                .collect::<Option<Vec<Point2>>>()
+        };
+        // SolidCraft: each point is searched from the one before it, but the first has no
+        // hint, and a search without one can miss a point that lies on the surface (a corner of
+        // a fillet strip on a surface extended past it, #882): the whole face was then left
+        // unmeshed. When the walk fails, it is tried once more from the first point an unhinted
+        // search finds. A walk that succeeds is kept as it is (where a loop starts decides how
+        // it is laid out across a periodic surface's seam).
+        let mut vec = match walk(bdry3d.clone()) {
+            Some(vec) => vec,
+            None => {
+                let start = bdry3d.iter().skip(1).position(|pt| sp(surface, *pt, None).is_some())? + 1;
+                let mut rotated = bdry3d;
+                rotated.rotate_left(start);
+                walk(rotated)?
+            }
+        };
         let grav = vec.iter().fold(Point2::origin(), |g, p| g + p.to_vec()) / vec.len() as f64;
         if let (Some(up), Some((u0, _))) = (up, urange) {
             let quot = f64::floor((grav.x - u0) / up);