Keyboard shortcuts

Press ← or → to navigate between chapters

Press S or / to search in the book

Press ? to show this help

Press Esc to hide this help

Sheet metal

The SHEET METAL tab builds parts from a sheet of constant thickness under a sheet metal rule (thickness, bend radius, K-factor), set in Sheet Metal Rules (sheet.manage_rules).

  • Flange (sheet.flange): a base flange from a sketch profile, a contour flange from an open sketch, or an edge flange from a part edge.
  • Hem (sheet.hem) and Fold (sheet.fold) along a sketch line.
  • Unfold / Refold (sheet.unfold, sheet.refold) for working on the flat part.
  • Convert (sheet.convert) turns a solid of constant thickness into sheet metal.
  • Create Flat Pattern (sheet.flat_pattern) shows the flat part with its bend lines and a bend table, and exports it as DXF or a bend-table CSV through the save picker.

Bends follow the rule’s K-factor, so flat lengths match what a press brake will make. The oracle checks these against parts built in Fusion.

For a shop drawing or spreadsheet, sheet.export_bend_table returns CSV by default; choose format: "json" for structured data. It includes the sheet rule, thickness, bend angles, radii, allowances and flat centre-line coordinates. Lengths use millimetres and angles use degrees. Supply path to save it, or omit path to receive the content through the command response. body defaults to the last sheet body. Exporting does not add a timeline entry or consume an undo step.

{"command":"sheet.export_bend_table","params":{"format":"csv","path":"bracket-bends.csv"}}
{"command":"sheet.export_dxf","params":{"path":"bracket-flat.dxf"}}

DXF cutout geometry preserves lines, circles and circular arcs; other curves are sampled adaptively. The OUTLINE, BEND_UP and BEND_DOWN layers separate cuts from bend centres.

Base-flange profiles keep their interior holes. Through cuts that cross a sheet edge become notches in the flat outline; overlapping and repeated cuts remove their combined area once. The flat preview, DXF and unfolded solid use the same material boundaries. Lines and circular arcs remain exact; other profile curves use a 0.001 mm chord tolerance.

Cuts can leave separate material pieces, including the centre of a ring cut. These pieces remain one logical sheet group through Unfold / Refold and export as separate flat outlines. Large profiles that exceed the geometry processing budget report an error instead of exporting a partial outline.

Parallel, untapered extrude cuts also preserve shallow pockets through Unfold / Refold. The pocket floor and side walls remain solid geometry; overlapping cuts from opposite sides become a through hole wherever they remove the whole thickness. Flat-pattern JSON lists pockets with their side, depth and bottom/top thickness coordinates in millimetres. DXF pocket boundaries use POCKET_BOTTOM_Z…_TO_…_MM, POCKET_TOP_Z…_TO_…_MM, or POCKET_INTERNAL_Z…_TO_…_MM layers. These are machining operations, so do not treat every pocket layer as a through-cut contour when importing the drawing into a CAM tool.

Extrude Intersect on a straight base or an unfolded sheet retains the material inside both the current tool footprint and its depth interval, including interior holes, detached islands and earlier pockets. A shallow intersection records the removed layers above and below the retained material as top and bottom pockets. The sheet rule keeps the original stock gauge; the remaining solid can be thinner. A completely empty intersection removes the sheet and its metadata together. DXF records pocket depth in its layer names; importing that DXF as ordinary sketch geometry does not reconstruct the machining depths automatically. Each positive retained or removed depth layer must meet the kernel’s 0.000001 mm extrusion resolution; smaller layers report an error rather than being rounded away. To Object can retain a tool that trims to a straight prism, using its actual trimmed footprint. A curved tool with varying depth is refused before changing sheet geometry. Pocket profiles can move with planar panels when forming, but a pocket crossing a bend zone cannot yet be refolded. Machining folded bend material, tapered sheet cuts and other unsupported 3D sheet Cut/Intersect operations report an error before changing the design; they cannot silently restore removed material during a later sheet rebuild.