A stencil-to-assembly release connects the paste-printing definition to the actual PCB, component population and assembly revision. It should identify who owns aperture design, which files are approved and how a change is communicated. Treat the stencil as a controlled manufacturing item rather than an attachment that can be reused without checking the board revision.
Align the board and population variants
Confirm the board side, panel drawing, fiducials and assembly variant. Check which components are fitted, omitted or installed by another operation. A paste layer exported from CAD may need an engineering review for the intended assembly process. Keep that review separate from changing the electrical design: record the approved aperture file and the reason for any deviation from the supplied paste artwork.
When several variants share a bare board, do not assume that the same paste pattern suits every population. Review unpopulated fine-pitch footprints, optional connectors and any area where deposited paste could affect inspection or downstream handling. The accepted solution belongs in the manufacturing instructions for the specific variant.
Define the stencil release record
| Item | Release information |
|---|---|
| Identity | PCB revision, assembly revision, board side and variant. |
| Geometry | Approved paste artwork, panel orientation and applicable aperture changes. |
| Process assumptions | Proposed stencil construction and paste system, subject to process review. |
| Ownership | Who approves changes, stores the stencil and authorizes reuse. |
| Verification | First-article checks and criteria for resolving printing findings. |
Connect printing to the complete assembly process
Printing, placement and reflow interact. Review the smallest apertures, large thermal pads and components with different paste-volume needs as part of one process plan. Define which measurements or observations will be used during the first build and who can approve a process adjustment. A visual check of the stencil alone does not establish finished solder-joint quality.
For example, an engineering change may move a component while retaining the same board outline. A stencil that fits the panel mechanically can still belong to the wrong revision. Match the stencil identifier to the controlled assembly package before material is released to the line.
RFQ and production checklist
- Supply the released copper, mask and paste data with the fabrication and panel drawings.
- Identify fitted and do-not-populate parts for each variant.
- Provide component data relevant to special pad or soldering requirements.
- Agree the first-article review, documentation and change-approval process.
- State whether tooling is new, reusable or customer-owned.
Factory equipment, available stencil processes and validated assembly limits are [NEEDS CLIENT INPUT]. Use the SMT assembly requirements and DFM checklist to define your project. Request an assembly review