CMM Inspection Report: Example, Template and Checklist

Search for "CMM report" and you get two different things: the results printout your CMM software produces, and the dimensional inspection report your customer actually signs. This post is about the second one. What a CMM inspection report must contain, what a real one looks like with out-of-tolerance readings in it, a template you can copy, and how to produce the report without retyping a single number.

A CMM printout is not a CMM inspection report

PC-DMIS, Calypso, MCOSMOS and PolyWorks all produce a results file at the end of a program: feature names, actuals, deviations, in program order, in machine terms. CIR1, PLN2, PNT14. That file is complete and correct, and nobody outside the metrology room can read it.

The customer wants something else. The same numbers, but organized by balloon number on the drawing, with the nominal and tolerance taken from the drawing, one column per serial number, out-of-tolerance readings visible at a glance, and traceability: who measured, when, on which machine, against which revision. That translation is the CMM inspection report, and the CMM results file is only one of its inputs. Hand gauges, thread gauges and visual checks feed the same report.

What a CMM inspection report must contain

Every customer template looks a little different, but the content is stable. If one of these blocks is missing, expect the report to come back.

Block	Fields	Why it matters
Header	Customer, part name, drawing number, revision, inspector	A report against the wrong revision is worthless, however accurate the numbers.
Order block	Order number, machine, sample size, unit, date	A missing unit is the most common reason a report is rejected. mm or inch, on the page.
Characteristic rows	Balloon number, zone, nominal, tol +, tol −, measuring tool	One row per balloon, in drawing order, so the reviewer can follow the drawing with a finger.
Readings	One column per serial number	Five parts means five columns, not five reports. Patterns across parts only show up side by side.
GD&T	Symbol, datum references, MMC or LMC modifier, bonus tolerance	A position of 0.1 at MMC is not a position of 0.1. The bonus must be on the page next to the reading.
Verdict	Out-of-tolerance cells highlighted	Nobody reads a deviation column. A highlighted cell is read in half a second.
Sign-off	Inspector, date, page x of y, drawing number on every page	Pages get separated. Each one has to stand alone in an audit binder.

A worked CMM report example

The report below is a real export: a machined part with 20 ballooned characteristics measured on 5 serial numbers, 100 readings in total, most of them from the CMM, two threads checked with a gauge. Read it the way a customer's incoming inspector would.

• Balloon 2.2, Ø6 ±0.1. Serial 1 reads 6.215 and serial 4 reads 6.144. Both over the upper limit, both highlighted. Serials 2, 3 and 5 are fine, so this is not a tool offset, it is two individual parts.
• Balloon 3.1, position 0.1 at MMC. Every serial reads 0.034, and next to each reading the report shows the bonus tolerance earned from the actual feature size, 0.137. The effective tolerance is 0.237, the feature passes comfortably. This is the row that a spreadsheet gets wrong, because someone compares 0.034 to 0.1 and forgets the bonus, or applies it when the modifier is not there.
• Balloon 5, M5×0.8 thread. Checked with a go/no-go gauge: Yes, Yes, No, Yes, Yes. There is no number to record, and the report handles that without a fake decimal.
• Balloon 9.1, 7.5 ±0.2. Serial 2 reads 7.246 and serial 4 reads 7.863, while balloons 9.2 to 9.5, the same feature repeated, are all in. Two identical features scattering on the same two parts points at fixturing on those parts, not at the program. The side-by-side layout is what makes that visible.

Free CMM report template

If you build the report in a spreadsheet, use this column layout. It is the same structure as the example above, and it is the structure most aerospace and automotive customers accept without asking for changes.

Four rules keep the template usable:

1. Nominal, tol + and tol − are three cells, never one. "6 ±0.1" in a single cell cannot be checked by a formula. With three cells the verdict is =OR(reading > nominal + tolplus, reading < nominal + tolminus), with tol − entered as a negative number.
2. One column per serial number, one row per balloon. Never one sheet per part.
3. Add a bonus column for every GD&T row with an Ⓜ or Ⓛ modifier, calculated from the actual size of that feature on that serial. If you cannot fill it, you cannot claim the pass.
4. Put the drawing number, revision and unit in the print header, so they repeat on every page.

The balloon numbers themselves come from the drawing. If yours is not ballooned yet, the free drawing ballooning tool numbers every dimension in the browser with no login; the matching inspection report sheet, as PDF and Excel, is unlocked with credits you earn inside the tool.

From CMM data to the report without retyping

A 20-balloon, 5-piece report is 100 numbers. At ten seconds each to find, type and double-check, that is 17 minutes per batch, and one transposed digit is enough to fail an audit. The whole point of importing CMM data into the inspection report is to remove the retyping step entirely.

1. Balloon the drawing. Manually, or with automatic dimension detection on a paid plan. Either way you end up with the characteristic list: balloon number, nominal, tolerances, GD&T modifiers.
2. Export the CMM results. CSV, Excel or text from PC-DMIS, Calypso or MCOSMOS. Our MCOSMOS export guide shows the exact settings for Mitutoyo machines.
3. Map features to balloons once. CIR1 is balloon 2, PLN2 is balloon 1. The mapping is saved with the part and reused for every following batch, so the second report of the same part number takes seconds.
4. Let the tolerance check run. Every reading is compared to the drawing tolerance, MMC and LMC bonus is calculated from the measured size, and out-of-tolerance cells are highlighted. No formulas to maintain.
5. Export the PDF. Your header, your logo, one column per serial number, page numbers, drawing number on every page. The same data also feeds an AS9102 first article report when the customer asks for one.

The CMM already measured everything. The report should be a view of that data, not a second job.

CMM report checklist before you send it

1. Drawing number and revision match the drawing the parts were made to.
2. Unit is printed. mm or inch, on the page, not assumed.
3. Every balloon on the drawing has a row. No skipped numbers.
4. Every serial number has a column. Sample size in the header matches the column count.
5. Every GD&T row with a modifier shows the bonus, and the verdict uses it.
6. Every out-of-tolerance reading is highlighted, and there is a note or a rejection decision for each one.
7. Threads and go/no-go checks are recorded as a result, not as an invented number.
8. Inspector name, date and page x of y appear on every page.

CMM report FAQ

What is a CMM report?

A CMM report is the dimensional inspection report built from coordinate measuring machine results: each ballooned characteristic of the drawing with its nominal, tolerance, the measured value for every serial number, and a pass or fail verdict. It is not the raw results printout from the CMM software.

What should a CMM inspection report include?

A header with customer, part, drawing number, revision, inspector, order, machine, sample size, unit and date; one row per balloon with nominal, plus and minus tolerance and measuring tool; one column per serial number; GD&T modifiers with any MMC or LMC bonus shown next to the reading; highlighted out-of-tolerance cells; and a sign-off with page numbers.

How do I create a CMM report from CMM data without retyping?

Balloon the drawing so each characteristic carries its nominal and tolerance, export the results from PC-DMIS, Calypso or MCOSMOS, map each measured feature to its balloon once, and let the software compare every reading to its tolerance and produce the PDF. The mapping is reused for every later batch of the same part.