Short answer: A stamped part inspection plan should focus on critical dimensions that affect fit, function, safety, electrical whakapā, welding, sealing, or automated assembly. Mark CTQ dimensions on the drawing, define datums, choose practical gauges, state sample frequency, and confirm report requirements before production. Over-inspecting every dimension increases cost without improving useful control.
This guide is for quality engineers, sourcing teams, and product engineers preparing RFQs for stamped brackets, clips, contacts, terminals, shields, busbars, and assemblies. It helps buyers ask for the right inspection without turning every drawing note into a cost driver.
If you need kaiwhakarato feedback on inspection planning, send drawings and quality requirements through the RFQ form. Related references include the first article inspection checklist, tolerances guide, and kaiwhakarato quality audit checklist.
What makes a dimension critical?
A critical dimension is one that can cause a real failure if it is out of control. It may affect bolt fit, connector insertion, solder whakapā, weld location, spring force, cover sealing, safety clearance, or automated loading. Critical does not mean “important-looking.” It means the dimension has a defined function.
Buyers should mark critical-to-quality dimensions on the drawing or in a separate inspection plan. If the kaiwhakarato does not know which dimensions drive function, they may spend time inspecting easy dimensions while missing the ones that stop assembly.
Inspection plan building blocks
| Plan item | Purpose | RFQ detail |
|---|---|---|
| CTQ dimensions | Focus inspection on fit and function. | Mark holes, bends, heights, whakapā points, or weld pads. |
| Datums | Make measurements repeatable. | Define the locating face, hole pattern, plane, or fixture reference. |
| Gauge method | Controls how parts are checked. | Caliper, height gauge, pin gauge, CMM, vision, or go/no-go fixture. |
| Frequency | Balances risk and cost. | FAI, setup check, hourly check, lot sample, or 100 percent check. |
| Report format | Prevents missing documents at shipment. | Dimensional report, material cert, plating cert, or PPAP-like package. |
Choose measurement methods that match the feature
A caliper may be fine for an outside width, but it may not be enough for small terminal geometry, coplanarity, hole position from datums, or formed height. A pin gauge may quickly check a hole size. A height gauge or fixture may be better for bend height. A CMM or vision system may be needed for small features with datum relationships.
Inspection should match the condition in which the part functions. A free-state spring clip, clamped bracket, solder foot, or welded busbar may need different inspection setups. For related geometry concerns, review stamped part coplanarity, flatness and warpage control, and punched holes and slots.
Avoid inspection requirements that add cost without control
Some drawings ask for full inspection of many dimensions because the buyer wants caution. In tā, that can slow quoting and production without improving the part. A better plan uses first article inspection for full dimensional confirmation, then routine production checks for process-sensitive and functional features.
For high-volume parts, gauges and fixtures can reduce measurement time and improve repeatability. For low-volume or early pilot parts, a more flexible inspection method may be enough until the design is frozen. The pilot production launch checklist helps define that transition.
Connect CTQ dimensions to process controls
Inspection finds variation, but process control prevents repeat defects. If a hole location is critical, the die, pilots, strip feed, and sensor checks matter. If bend height is critical, material temper, grain direction, forming sequence, and springback control matter. If burr height is critical, clearance, tool wear, and sharpening schedule matter.
That is why inspection planning should connect to DFM. A kaiwhakarato can often suggest datum changes, tolerance changes, carrier support, or tool features that make the inspection requirement easier to hold. Arotake DFM review before tooling, mate ahu whakamua design checklist, and die maintenance and tool life.
RFQ checklist for inspection planning
- Drawing with CTQ dimensions, tolerances, and datum references marked.
- Wāhanga function: fit, weld, solder, spring force, seal, safety, or assembly location.
- Koeke rauemi, thickness, temper, and finish, since these affect measurement.
- Preferred inspection method or openness to kaiwhakarato recommendation.
- FAI, dimensional report, material certificate, plating certificate, or PPAP-like need.
- Sampling plan, lot traceability, label format, and revision control requirement.
- Known past defects, customer complaints, or current kaiwhakarato problems.
Tukuna these details through the whakapā page for review. For broader sourcing context, also see Custom tā konganuku, products and services, and tā konganuku RFQ checklist.
FAQ: stamped part inspection plans
Should every dimension be inspected on wāhanga kua tāngia?
No. Full inspection may be useful for first article approval, but routine production checks should focus on CTQ dimensions, process-sensitive features, and agreed sampling rules.
What dimensions are usually CTQ in tā?
Tikanga CTQ dimensions include hole position, bend height, formed angle, whakapā height, coplanarity, weld pad position, spring features, and safety-related edges.
When is a custom gauge worth using?
A custom gauge is often useful for high-volume parts, fast setup checks, difficult datum relationships, or features that must match an assembly condition.
What documents should be requested with first samples?
Typical first sample documents include a dimensional report, material certificate, finish certificate if applicable, drawing revision, and notes on any open DFM or tolerance issues.