Inspection is a buyer topic
It is tempting to file inspection under "factory business" and sign whatever arrives. That is how mixed shipments and silent drift happen. The whole point of a spec sheet program is that the sheet you approved is the sheet that ships, and inspection is the mechanism that proves it - or catches it failing. A buyer who knows the checks can ask precise questions at quotation, read the reports at delivery, and argue from evidence rather than impression. The desk's position is simple: inspection runs against the approved sample and the written sheet, never against memory or a catalog photo. The formal home of this is the quality control page; this note is the working checklist.
Check one: geometry, measured optically
The core check is optical profile measurement of the tool's geometry - diameter, length of cut, the flute profile and the corner treatment, measured against the numbers on the sheet. Optical measurement matters because cutting edges are too fine for touch probes to measure without distorting what they touch, and because a profile scan catches what calipers cannot: a helix that wandered, a gullet that came out shallow, a corner radius that drifted from the drawing. This is the check that answers the questions distributors actually get returns about - "is this really the diameter on the label" - and it is the check the approved sample anchors: bulk is compared to the sample and the sheet, not to intention. The size lines it verifies are the ones in the sizes reference.
Check two: runout at the cutting edge
Runout - the total indicator reading at the cutting edge - measures how much the cutting edges wander from the true rotation axis. It is checked on every inspected program because it is the quiet variable behind uneven wear, chatter complaints and short life: an edge that runs out takes more than its share of the chip load and fails first, and the customer blames the tool rather than the runout. The acceptance level is set per program and written on the spec sheet - the desk does not quote general runout numbers in the abstract, because the sensible acceptance depends on the tool and the application. What you should insist on is that the check exists, the acceptance is written, and the measurement is done at the cutting edge, where it matters. The full story is in the runout and tool life note.
Check three: the edge and the coating
The third family of checks looks at the edge itself and whatever sits on it. Edge condition: the honed edge should match the prep line on the sheet - stable, without grinding burrs or micro-chipping. Coating: for coated programs, the family named on the sheet should be the family on the tool, and coating adhesion spot checks run per the QC plan - the standard failure a spot check catches is a coating that lifts at the edge under load, invisible in the box. Surface finish: polished flutes should read polished, at the level of the approved sample. None of these checks requires laboratory equipment to specify - they require that the sheet names them, and that the plan says they run.
| Check | What it covers | What the buyer gets |
|---|---|---|
| Optical geometry | Diameter, LOC, flute profile, corner, against the sheet | Confirmation the sheet that shipped matches the sheet approved |
| Runout at the edge | Edge wander from the rotation axis | Acceptance level written per program |
| Edge condition | Honed edge per the prep line; no burrs or chipping | Sample-matched edge quality |
| Coating and adhesion | Family per sheet; adhesion spot checks per plan | Coated tools that survive handling and load |
| Marking | Geometry code, logo under private label | Marks proofed against the approved sample |
| Packing | Boxes labeled, typically 10 pcs per box, cartons sealed | Labels that match contents; transit protection |
Sample stage versus bulk stage
Inspection runs twice in a program's life, and the two runs answer different questions. At the sample stage, the question is definition: does this factory's interpretation of your sheet match your intent? You inspect the sample against the drawing and the sheet - geometry, edge, coating, mark, box - and either approve it or send back corrections. At the bulk stage, the question is fidelity: does production match the approved sample? The same checks run, now with the sample as the physical reference. Buyers who skip reading the sample carefully lose their anchor; buyers who skip asking what runs at bulk lose the protection the anchor was for. Timing for both stages, in typical reference ranges, is on the MOQ and lead time page, confirmed in writing per program.
The papers that travel with the shipment
Inspection ends in documents, and the documents are what a brand or distributor can actually show a customer. Two papers are standard on desk-run programs: the certificate of conformance for the shipment, and material certificates for the substrate - the mill certificate evidencing the carbide or HSS grade. Both are provided per program in writing. They connect to the checks: the conformance certificate asserts the checks ran and passed, the mill certificate evidences the grade line on your sheet. What the papers do not do is substitute for the checks - a program that offers certificates without naming the inspection behind them has the paperwork backwards. The compliance context, including what US import paperwork these support, is on the compliance page.
For buyers: what to settle in writing
- The QC plan as a document. Which checks run, at which stage, against which reference - sample and sheet - in writing, before bulk.
- Runout acceptance per program. The level written on the spec sheet, measured at the cutting edge.
- Adhesion in the plan. Coating adhesion spot checks named for coated items.
- Sample discipline. The approved sample is the reference; changes after approval restart the clock.
- Papers per shipment. Certificate of conformance plus material certificates, per program in writing.
Want a QC plan attached to a quote? Send the sheet through the quote form and ask for the inspection plan as part of the first reply.