STEP, STL and PDF: Which Files Should You Send for a Quote?

The most useful quotation package combines a clear shape definition with requirements that a model alone may not communicate. File choice depends on the process and the information available.

Use a solid model where possible

For machined components, a STEP or IGES file can communicate the three-dimensional geometry. Check the units and the intended revision before exporting. If several components are included, identify which bodies are separate manufactured parts and which are only assembly references.

Check mesh files before printing

An STL or 3MF may be appropriate for a printing inquiry. Check that the geometry is complete and that scale is unambiguous. A coarse mesh can make a curved surface look faceted; exporting a new mesh from the original CAD is preferable to hiding that problem with a cosmetic finish.

Add a requirements drawing

Use a PDF to communicate threads, fits, critical dimensions, surface requirements and inspection notes. State which document governs if the drawing and model conflict. A supplier should request clarification rather than silently choosing a conflicting value.

Make the package easy to identify

Name each file with a part number and revision. Include quantity, material, finish and any assembly context in a short accompanying brief. If the design is still changing, say which features are provisional and which must be preserved.

Discuss your project

Share your model, drawing revision, quantity and application with Winston Rapid. Material availability, manufacturing feasibility, inspection requirements and delivery are confirmed during quotation.