What is the difference between AAMA and ASTM DXF?
The format began as the American Apparel Manufacturers Association’s DXF convention and was later standardised by ASTM International as ASTM D6673. Both describe the same kind of file, with the same numbered layers; Lescut reads either one, and recognises it by its layer 1.
Which layers does a pattern DXF use?
Each piece is usually a block. The layers that matter most for a marker:
| Layer | Holds | How Lescut reads it |
|---|---|---|
| 1 | The piece boundary (cut line) | The outline that is nested and cut |
| 11 | Internal cut-outs | Holes in the piece, also cut |
| 7 | Grain line | The piece’s starting direction on the roll |
| 6 | Mirror line | A fold line, for pieces cut on the fold |
| 4 | Notches | Kept with the piece in the cutting file |
| 13 | Drill holes | Kept with the piece |
| 14 | Sew lines | Kept with the piece |
| 15 | Annotation text: name, size, quantity | Read for the piece’s options, kept with it |
Every other numbered layer, such as grade reference or stripe and plaid reference lines, also travels with its piece into the cutting file. Only layers 1 and 11 are cut.
How are sizes and quantities read?
Annotation text inside each piece gives its name, size and quantity: Piece Name: FRONT, Size: M, Quantity: 2 (the short forms NAME:, SIZE: and QTY: work too). Each size of a piece becomes its own part, named with its size, and keeps that size on its label and in report.csv.
The quantity is per set. One set is everything the file holds: for a marker of sizes S, M and L, one set is one S, one M and one L garment, and the number of sets says how many of those the marker holds.
Where do plies come in?
A marker is nested once and cut through every ply of the spread at the same time, so the fabric a cut uses is the marker length times the number of plies. Which sizes, ratios and plies make up a cut is cut planning, decided in your pattern CAD or planning system: Lescut nests the pieces you export and does no grading or cut order planning.
Marker length is a trade-off with plies: a marker over about 15 m is hard to spread and cut, so for a long marker Lescut suggests nesting fewer sets on more plies, with a number of sets that divides the order.
What happens to notches, drill holes and sew lines?
They are never cut as outlines. Each mark goes with the piece it lies in; a short mark of up to 20 mm just outside every piece, as notches drawn on the edge often are, goes with the nearest outline within 5 mm. A notch that belongs to no piece is reported on import rather than guessed. In the cutting files a cutter profile can send each layer to the right tool, such as a notcher, drill or pen.
How do grain and mirror lines set the direction?
The grain line on layer 7 is laid along the roll. A piece with a grain line and no rotation rule may turn only by half turns, which keeps it on grain; a ROT: text or the parts table can allow 90° steps or free rotation, TILT: a few degrees off grain, and FLIP: mirroring.
A mirror line on layer 6 along the edge of a half piece marks a piece cut on the fold. On folded or tubular fabric that edge goes on the fold and is not cut; on open fabric the half piece is nested as drawn, and you are told so.
Which export problems should you check?
- An open boundary: a piece needs a closed outline on layer 1.
- A boundary that crosses itself: the file is refused with the piece to fix.
- Units: Lescut reads the units the DXF declares, and assumes millimetres when it declares none.
- A grain line outside every piece: it is reported, not assigned to a guessed piece.
- Missing sizes: without a Size text, pieces of different sizes with the same name are numbered, not labelled by size.
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