{ "id": "36-corner-blend-two-radii", "name": "Corner blends with two radii", "description": "50x40x30 box; 4 vertical edges R8, then the top-face loop R4 (tangent chain) - 3-edge corner blends with unequal radii.", "exercises": [ "fillet", "corner_blend", "tangent_chain" ], "units": { "length": "mm", "angle": "deg", "area": "mm2", "volume": "mm3" }, "conventions": { "world": "right-handed; Z up. XY/XZ/YZ are the origin planes.", "sketch_frame": "sketch-local 2D coords; world = plane.origin + x*plane.x_dir + y*plane.y_dir (origin in mm). Profile 'loops' list sketch entity ids.", "point_refs": "'.start' / '.end' / '.center' reuse (share) that existing sketch point; 'at' is its position when referenced.", "extrude_direction": "positive = along sketch plane normal unless stated", "selections": "selected faces/edges carry 'point': a world-space point on the face / the edge's parametric midpoint; pick the nearest face/edge to it." }, "parameters": [], "features": [ { "op": "sketch", "name": "Extrude1_sketch", "plane": { "ref": "XY", "origin": [ 0.0, 0.0, 0.0 ], "x_dir": [ 1.0, 0.0, 0.0 ], "y_dir": [ 0.0, 1.0, 0.0 ], "normal": [ 0.0, 0.0, 1.0 ] }, "entities": [ { "type": "line", "start": { "at": [ 0, 0 ] }, "end": { "at": [ 50, 0 ] }, "id": "l1" }, { "type": "line", "start": { "ref": "l1.end", "at": [ 50.0, 0.0 ] }, "end": { "at": [ 50, 40 ] }, "id": "l2" }, { "type": "line", "start": { "ref": "l2.end", "at": [ 50.0, 40.0 ] }, "end": { "at": [ 0, 40 ] }, "id": "l3" }, { "type": "line", "start": { "ref": "l3.end", "at": [ 0.0, 40.0 ] }, "end": { "ref": "l1.start", "at": [ 0.0, 0.0 ] }, "id": "l4" } ], "constraints": [], "dimensions": [] }, { "op": "extrude", "name": "Extrude1", "operation": "new", "profiles": [ { "sketch": "Extrude1_sketch", "loops": [ { "outer": true, "curves": [ "l1", "l2", "l3", "l4" ] } ] } ], "extent": { "type": "distance", "distance": 30, "direction": "positive" }, "result_bodies": [ "Box" ] }, { "op": "fillet", "name": "VerticalFillet", "type": "constant_radius", "radius": 8, "tangent_chain": false, "edge_selection": "the 4 vertical edges", "edges": [ { "type": "line", "start": [ 0.0, 40.0, 0.0 ], "end": [ 0.0, 40.0, 30.0 ], "point": [ 0.0, 40.0, 15.0 ] }, { "type": "line", "start": [ 50.0, 40.0, 0.0 ], "end": [ 50.0, 40.0, 30.0 ], "point": [ 50.0, 40.0, 15.0 ] }, { "type": "line", "start": [ 50.0, 0.0, 0.0 ], "end": [ 50.0, 0.0, 30.0 ], "point": [ 50.0, 0.0, 15.0 ] }, { "type": "line", "start": [ 0.0, 0.0, 0.0 ], "end": [ 0.0, 0.0, 30.0 ], "point": [ 0.0, 0.0, 15.0 ] } ] }, { "op": "fillet", "name": "TopFillet", "type": "constant_radius", "radius": 4, "tangent_chain": true, "edge_selection": "one edge of the top face + tangent chain (whole top loop)", "edges": [ { "type": "arc", "start": [ 8.0, 0.0, 30.0 ], "end": [ 0.0, 8.0, 30.0 ], "center": [ 8.0, 8.0, 30.0 ], "axis": [ -0.0, -0.0, -1.0 ], "point": [ 2.343145751, 2.343145751, 30.0 ] } ] } ] }