What to request in a CNC inspection report before mass production

A good inspection plan starts from the drawing. Critical-to-function dimensions, datum references, threads, fit interfaces, flatness, perpendicularity, and surface requirements should be clearly marked before machining.

For prototype validation, request a first article inspection report. For repeat production, define sampling level, gauge method, and when CMM data is required. This prevents over-inspection on simple dimensions while protecting high-risk features.

Surface finishing also needs inspection language. Anodizing thickness, masking area, cosmetic side, color sample, and post-finish dimensional checks should be part of the approval path when the part is appearance-sensitive.