Flat Pattern
Updated v2.4.7At a glance
- Unfold a sheet-metal part to the flat shape you'd actually cut — one right-click
- Correct developed lengths from the part's material, thickness, and K-factor
- Outline and holes come through as real geometry; each fold lands as a bend line on its own layer
- Mitered corners, hems on every side, bends split by slots — the pattern comes out true, with every fold line at full length
- Slots and rounded cutouts through any wall unfold as the cut edges they are — never mistaken for bends
- Complete or clearly refused: every wall and bend is verified into the pattern, and if one can't be developed you're told — never a partial outline
- Bend lines are blue construction geometry — they read as folds and are skipped automatically when you import the flat into Plasma or Laser
- Optional EZ Bend reliefs: cut perforations or slots along each fold and bend the part by hand
- The result is a normal sketch: export it, or send it to Plasma / Laser and cut
Right-click a Sheet Metal Base in the browser tree, choose Flat Pattern, and the whole part — base plus every flange and bend — is developed onto the XY plane. The dialog sets the sketch name and how folds come through: classic bend lines, or cuttable EZ Bend reliefs for bending without a press brake. Holes and cutouts land in the right place on the flattened wall, and each fold is drawn as a bend line on a dedicated Bend Lines layer you can keep or hide.
Developed length
Each bend is flattened with the true bend allowance for the part's material, thickness, and radius — the same numbers that drive the 3D bends — so the flat length is what actually comes off the brake, not a straight-line guess.
A snapshot you can cut
The flat pattern is a point-in-time sketch: change the part and run Flat Pattern again for a fresh one. Parts built from flat panels and cylindrical bends unfold cleanly; an unsupported face (like a filleted skin) reports a clear message instead of producing a bad pattern.
Real parts unfold true, not just textbook ones: mitered corners between flanges or hems, a hem on all four sides, a bend interrupted by a slot or cutout — each bend is read as the single fold it really is, every fold line spans its full length, and every wall lands square on the sheet. Slots and rounded-corner cutouts punched through a wall come through as the cut openings they are — their rounded ends are never misread as folds.
Complete, or it says so
A pattern you get is a pattern you can cut. The unfolder verifies that every wall and every bend of the folded part made it into the flat before handing it over; if something genuinely can't be developed, Flat Pattern stops with a clear message instead of quietly leaving a wall out of the outline. It also picks the development route that covers the most of the part on its own, so an imperfection in one face of the folded model doesn't cost you the pattern.