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AMPROTOPrecision

Process assurance

A tolerance is a promise. Inspection is how it is kept.

Quality control is a sequence of measurements at defined points, not a final visual check. Nothing on this page is a certification claim.

Inspection sequence

Four points where a part is measured.

  1. 01

    Design review

    Critical dimensions, datum structure and tolerance callouts are reviewed before programming, so a drawing that cannot be inspected is caught before machining starts.

  2. 02

    In-process inspection

    Parts are inspected at stages during production rather than only at the end, so a drift is corrected while the setup is still on the machine.

  3. 03

    Final inspection

    Finished parts are measured against the drawing and the agreed specification before packing. Results are supplied with the shipment.

  4. 04

    Assembly check

    Where AMPROTO assembles the product, fit and function are checked during build, so a stack-up problem surfaces before the unit is closed.

Inspection equipment

Two ways a part is measured: on a CMM and at the bench.

Coordinate measurement where a drawing has to be proven feature by feature, and bench instruments for the checks that happen during a run.

A coordinate measuring machine probe head above a granite surface plate, with a part clamped in a vice and gauge blocks set out beside it.
Coordinate measuring machine — probe head over the granite surface plate
An inspection bench: a micrometer head on a stand, a height gauge with a digital display and a dial indicator on a magnetic base, with a machined boss in the foreground.
Bench inspection — micrometer, height gauge and dial indicator

Tolerance basis

The drawing decides, not the default.

Where a drawing is silent, ISO 2768 applies. Where it is not, the drawing governs and the part is inspected to that callout.

Standard basis
ISO 2768 for general tolerances, where the drawing does not call out tighter limits
Metals
±0.005 in (±0.127 mm) general, tighter to drawing
Plastics and composites
±0.010 in (±0.254 mm) general, tighter to drawing
Precision features
Down to ±0.001 in on milled features, inspected to the drawing and GD&T

Certification

No certification is published here.

The legacy site refers to adherence to industry standards and to ISO quality management. It does not publish a certificate number, issuing body, scope or validity date. Until those documents are supplied and checked, this page states process controls only — it makes no certification claim.

None published — awaiting certificate evidence from AMPROTO.

Next step

Have an inspection requirement?

First-article inspection, material certificates, a specific GD&T callout or a documented inspection report — say what is needed at quotation and it becomes part of the scope.

Start a projectinfo@amprotoprecision.com