A polished 3D garment is convincing, but a factory cannot cut from a render. To move from a virtual sample to a physical product you need a tech pack: the structured document that tells a manufacturer exactly what to make, from stitch type to button count. The good news is that a well-built 3D file already contains most of the data a tech pack needs.
This article explains how to derive a production-ready tech pack from a 3D sample: which artifacts to extract, how to turn the digital pattern into a graded spec, and how to capture the construction detail that lives in your head but not yet on the page.
What a tech pack must contain
- Technical flats of front, back and any relevant detail views.
- A points-of-measure table with tolerances for every critical dimension.
- A bill of materials listing fabrics, trims, thread and labels.
- Construction and stitching notes, including seam types and finishes.
- Colorways, labeling, and packing or folding instructions.
Pro tip
A tech pack is a communication contract. Anything you leave unspecified, the factory will decide for you, and rarely the way you hoped.
Extracting flats and views from the 3D file
Most 3D software can render clean technical flats directly from the garment, either as a shaded front-and-back or as a line drawing suitable for annotation. These auto-generated flats are already in correct proportion, which removes the drudgery and inaccuracy of drawing them by hand from a sketch.
Capture the detail views that matter for construction, such as a pocket, a cuff or a vent, from angles that show how the piece is built. A reviewer who can see the detail rarely has to send a query back.
Turning the digital pattern into a graded spec
The pattern pieces inside the 3D sample are the same geometry a cutter needs. Export them and confirm the points of measure, then grade the pattern into your intended size range. The points-of-measure table in the tech pack should be generated from the graded pattern, not typed by hand, so the spec and the pattern can never disagree.
Pattern files travel best in neutral, interoperable formats. Exporting to DXF AAMA preserves piece geometry, notches and grainlines for the factory's CAD system, while PLT drives a plotter directly and PDF gives a human-readable reference. Minerva Patterns supplies patterns in exactly these formats for this reason.
Building the bill of materials
The bill of materials, or BOM, lists everything that goes into the garment with enough detail to source it: each fabric with its composition and weight, every trim with a placement and quantity, thread, interfacing, labels and hangtags. A vague BOM is the fastest route to a wrong sample and a delayed order.
Where your 3D file already carries validated fabric data, reuse it. The GSM and composition you entered to make the sample drape correctly are the same values a sourcing team needs, so a good fabric library feeds the BOM directly.
Capturing construction detail
- 1.Specify the seam type for each seam, such as plain, French or flat-felled.
- 2.State edge finishes and topstitching, including distance from the edge.
- 3.Note closure detail: button size and count, zip type and length.
- 4.Define hem depth and finishing method for every hemmed edge.
- 5.List any interfacing or reinforcement and where it is applied.
Pro tip
Photograph or annotate a reference detail whenever words risk ambiguity. A single close-up of a cuff often replaces a paragraph of instructions.
Versioning and revision control
A tech pack lives through many revisions as samples come back and corrections are made. Give every version a clear number and date, and log what changed between them so the factory always knows it is building from the latest spec. Sending an unlabeled updated file into an active order is a classic and costly mistake.
Keep the 3D sample, the pattern files and the tech pack in step. When one changes, the others usually must too, and a disciplined revision record is what keeps a development cycle from descending into confusion.
Frequently asked questions
Can I generate technical flats directly from a 3D sample?
Yes. Most 3D garment tools render correctly proportioned front, back and detail flats from the garment, which you then annotate. This is faster and more accurate than drawing flats by hand from a sketch.
What format should pattern pieces be in for a factory?
DXF AAMA is the industry standard for exchanging pattern geometry with a factory's CAD system, since it preserves pieces, notches and grainlines. PLT suits direct plotting and PDF gives a readable reference.
How detailed does the bill of materials need to be?
Detailed enough that a sourcing team could buy every component without asking you a question: composition, weight, placement and quantity for each material and trim. Vagueness in the BOM leads directly to wrong samples.
Minerva Patterns
Made-to-measure digital patterns, ready to cut
Every pattern is graded to your measurements and delivered as DXF AAMA, PLT and PDF files for cutting, plotting and 3D workflows.
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