Build to print is a manufacturing arrangement in which the supplier makes parts exactly to the customer's drawing, specifications, and revision, without changing the design. The customer owns the design and its performance, and the machine shop is responsible for producing parts that conform to the print and for documenting that conformance.
Most machined parts bought by OEMs and government agencies are purchased build to print. Understanding the model helps engineers and buyers define responsibilities clearly and avoid disputes over design issues versus manufacturing issues.
How build to print works
The customer supplies a drawing package: dimensioned drawings, 3D models, material and process specifications, and quality requirements. The machine shop reviews the package, quotes it, and produces parts that match. If the shop finds an error or ambiguity in the drawing, it asks the customer. It does not change the design on its own.
- The customer controls the design, revisions, and approvals.
- The shop controls the manufacturing method: machines, tooling, fixtures, and sequence.
- Acceptance is based on conformance to the drawing and PO requirements.
Build to print vs build to spec vs design and build
| Model | Who owns the design | Supplier responsibility |
|---|---|---|
| Build to print | Customer | Make parts that conform to the drawing |
| Build to spec | Shared; customer sets performance requirements | Develop details that meet a performance specification |
| Design and build | Supplier | Design and manufacture to meet stated function |
A precision machine shop working build to print can still offer manufacturability feedback, but the customer decides whether to revise the drawing.
What the customer provides in a build to print package
- Drawings at a released revision, with all tolerances, GD&T, finishes, and notes.
- 3D models matching the drawing revision, usually in STEP format.
- Material specifications, including condition and sourcing requirements.
- Process specifications for heat treat, plating, passivation, or other finishing.
- Quality requirements: inspection level, FAI, CMM reports, certs.
- Packaging, marking, and delivery requirements.
What the machine shop provides
- Drawing review and written questions at the quote stage.
- Manufacturing planning: machine selection, programming, fixturing.
- Material purchase to specification, with certs and heat traceability.
- Management of outside processing through qualified processors.
- Inspection to the drawing and the documentation required by the PO.
- Configuration control so parts are built to the revision ordered.
Common build to print issues and how to avoid them
Drawing and model disagree
If the model and drawing differ, the drawing usually governs, but confirm it on the PO. Keep both at the same revision.
Missing or outdated specifications
Old drawings sometimes reference superseded material or finish specifications. Update them or state accepted equivalents.
Revision confusion
The PO should state the drawing revision. A shop should not build to a newer revision without written direction.
Documentation in build to print work
In a build to print relationship, the documentation is the proof of conformance. The typical record set is:
| Document | Purpose |
|---|---|
| Material cert (MTR) | Shows the material meets its specification |
| Outside processing certs | Shows heat treat, plating, or passivation met its specification |
| First article inspection report | Shows every drawing characteristic was verified on the first part |
| CMM or dimensional report | Records measured values on critical features |
| Certificate of conformance | The shop's statement that the lot meets the drawing and PO |
Build to print also defines what happens when a part does not meet the drawing. The shop documents the nonconformance and asks the customer for disposition. The customer may accept as is, request rework, or reject. The shop does not decide on its own that a deviation is acceptable, because only the design owner can judge its effect on function.
Build to print at Wexmar
Wexmar is a build to print CNC machine shop. Parts are made on CNC lathes with live tooling and Y-axis, horizontal machining centers with pallet changers, and Swiss-type machines, and inspected on CMMs. Documentation includes material certs, CoC, CMM reports, and FAI in AS9102 format. See our capabilities, inspection and quality, and parts pages.
Build to print checklist
- Drawing and model at the same released revision.
- Revision stated on the PO.
- Material and process specs current and complete.
- Quality and documentation requirements listed.
- Contact named to answer drawing questions.
Getting a quote
Send your drawing package and Wexmar will quote it as drawn and note any questions. You can upload a drawing for an instant estimate or call (315) 400-2654.