Assemblies
Build a multi-piece product from several Print CAD configurations, position the pieces together with mates, and preview the assembled result in live 3D.
An assembly is a product made from more than one Print CAD piece — a box with a separate lid, a display with an insert, a carton with a tray. Instead of a single dieline, an assembly composes several existing single-piece configurations and describes how they fit together.
Once built, customers can view and play the assembled product in 3D on the storefront and in the Print Editor.
Assemblies require the CAD Assemblies license feature. When it is not enabled, the Assemblies tab is hidden and only single-piece configurations are available. Contact PrintNow support to enable it.
Single-Piece and Assemblies Tabs
The Custom Libraries list is split into two tabs:
- Single-Piece — standards backed by one
.pcaddieline file. This is the classic Print CAD configuration described throughout the rest of this section. - Assemblies — multi-piece configurations composed from those single-piece standards.
Both tabs share the same search box and list/grid view toggle. The tabs only appear when the CAD Assemblies feature is enabled; otherwise the list shows single-piece standards with no tab bar.
Create an Assembly
- From your Unified Admin, go to Products > Print CAD.
- Select the Assemblies tab.
- Click Create Assembly.
- Complete the dialog and click Create.
| Field | Description |
|---|---|
| Display Name | Required. The name shown to administrators and on the storefront. |
| Categories | The product category this assembly belongs to. Select None to leave it uncategorized. |
| Units | The unit system used for the assembly's dimensions and offsets. |
Unlike a single-piece standard, an assembly has no .pcad file of its own — it is composed entirely from its member pieces.
Add Pieces
The Pieces list defines which single-piece configurations make up the assembly. Use Add piece (from CAD configs) to pick an existing Print CAD standard, then click Add piece.
| Column | Description |
|---|---|
| Root | Marks the piece everything else is positioned relative to. Exactly one piece is the root; the rest are attached through mates. |
| Label | The name used for this piece throughout the assembly editor — in the mate dropdowns, the 3D preview, and the animation timeline. |
| Config | The single-piece Print CAD configuration this piece is built from. |
| Order | Display order of the piece in the list. |
| Remove | Removes the piece from the assembly. Mates that reference it become incomplete. |
Before any pieces are added the list reads "No pieces yet."
A piece's identity is fixed once created, because mates reference it. Changing a piece's Label is safe; removing and re-adding a piece is not — it breaks any mate pointing at it.
Position Pieces with Mates
A mate attaches one piece (the child) to another (the parent) by joining a panel on each. Every non-root piece needs a mate.
Choosing the panels
| Field | Description |
|---|---|
| Parent | The piece this one attaches to. The root piece is the usual starting point. |
| Child panel | The panel on this piece that meets the parent. Use Pick child panel in 3D to click it directly in the preview instead of selecting from the dropdown. |
| Parent panel | The panel on the parent piece the child attaches to. Use Pick parent panel in 3D to click it in the preview. |
A mate with a missing parent or panel is flagged as "Mate incomplete — set a parent and both panels."
Rotation and offset
Once both panels are chosen, six values control exactly how the child sits against the parent. Rotations are applied about the seam where the two panels meet:
| Field | Description |
|---|---|
| Rot X (hinge) | Rotation about the seam itself — the hinge angle, as if folding the child away from the parent. |
| Rot Y (tilt) | Tilt of the child relative to the seam. |
| Rot Z (spin) | Spin of the child in the plane of the joint. |
| Offset U | Slide along the first axis of the parent panel, as a fraction of that panel's extent. |
| Offset V | Slide along the second axis of the parent panel, as a fraction of that panel's extent. |
| Offset N | Offset along the parent panel's normal — lifting the child off the surface. |
Offsets are fractions of the parent panel's reference extents rather than absolute measurements, so a mate keeps its proportions when the assembly's parameters change the size of the pieces.
3D Preview
The preview renders the whole assembly live — each piece folded from its own dieline and placed according to its mate. Orbit, pan, and zoom with the mouse.
The preview is also an editing surface:
- Drag handles on a mate let you adjust its rotation and offset directly in 3D rather than typing numbers. The values in the mate form update as you drag.
- Panel picking — with Pick child panel in 3D or Pick parent panel in 3D active, clicking a panel in the preview assigns it to the mate.
If the preview cannot be built — usually because a member configuration failed to load — it reports "Couldn't resolve the 3D preview."
Assembly Parameters
An assembly carries its own parameters, separate from the parameters of its member pieces. Each has a name, a default, a minimum and maximum, a step, and a display order — the same shape as single-piece parameters. Use these to drive the dimensions customers can change on the storefront.
Related Pages
- Assembly Animations — author fold and assembly sequences on a timeline
- Custom Libraries Quick Start — the Print CAD admin basics
- User Interface — the Custom Libraries list, tabs, and bulk operations
- Parameters — parameter definitions on single-piece standards
- Panels — panel roles, which mates attach to
- Animations — fold animations for single-piece standards