In this guide 6 sections
Give every gauge a unique ID, an interval and a due date, then log each use against the job number and the part drawing revision. When a gauge fails calibration, the system lists every part it measured since its last good check, and those parts go into quarantine until someone assesses them. Record the decision.
Start with a register that names every gauge
Walk the floor and the tool crib. List every micrometer, bore gauge, thread plug, height gauge, CMM probe and torque driver, then give each one a unique ID and engrave it somewhere durable. No exceptions.
Record the fields you will need at recall time: size range, resolution, owner, location, calibration lab, certificate number and the last as-found result. No ID, no trace.
Include the quiet ones. Go/no-go pins in a drawer and hand gauges that travel with a job are the ones that slip past a due date. Torque drivers drift quietly.
- Gauge ID, type and size range
- Resolution and accuracy class
- Current location and responsible person
- Calibration lab and certificate number
- Status: in service, quarantined or retired
Set intervals from evidence, not habit
A twelve month interval for everything is easy to write and hard to defend, because used thread plug gauges wear faster than a granite surface plate that sits still.
Start with the maker’s advice and the customer’s requirements, then adjust from the as-found history of each gauge, stretching the interval after clean returns and cutting it after drift.
Write the reasoning next to the interval. An auditor will ask why a gauge sits on a twelve month cycle or a six month one, and a dated note from last year answers faster than memory.
Make due alerts reach the right person
A due date on a sheet only works if someone opens it, so alerts should reach the gauge owner two or three weeks ahead and again on the day.
Overdue gauges stop at the crib. The crib issues a gauge to a job only if its status reads in service and its date is valid, and a scanned label can enforce both checks.
Plan for the lab turnaround. Sending a CMM stylus out for ten days leaves a gap on the inspection schedule, so keep a spare or time the visit between jobs. A spare stylus, a second set of thread plugs or a loan gauge from the lab keeps the cell running while the original is away. Give a loan gauge its own ID.
- Alert to the gauge owner before the due date
- Escalation to the supervisor when overdue
- Block on issue when status is expired
- Spare gauge list for long lab turnarounds
Link every measurement to the gauge that took it
Recall only works if inspection results carry the gauge ID, so each reading on the first article report and the in-process sheet must name the instrument that took it.
Capture the part number, drawing revision, lot, operator and date at the same moment as the reading, because typing them later from memory is where the chain breaks.
Keep the calibration certificate as a file against the gauge and store the as-found readings, not only the pass mark, since those readings drive the recall decision.
Run the out of tolerance recall
Act on the day an as-found reading falls outside tolerance, by quarantining the gauge, tagging its drawer and pulling every part it measured since the last good calibration. No waiting for the next audit. Phone the customer’s quality contact before shipping anything further from the affected lots, since a notice that arrives early is cheaper to handle than one that arrives late.
Group the parts by job and customer. Some sit on the shelf. Some are in assembly. Others have shipped. Each group needs its own action, from re-inspection of shelf stock to a scrap decision for assembled units and a written notice to the customer for anything already shipped.
Record who decided what and why. Close the recall only when every affected part is accounted for, and then review the interval that failed, because a gauge that drifted once may drift again.
- Quarantine tag on the gauge and its drawer
- List of affected jobs and lot numbers
- Re-inspection or scrap decision per lot
- Customer notice where parts have shipped
Gauge recall worksheet
A one page worksheet in three blocks. Block one holds the gauge ID, last good calibration date and as-found result, and block two tabulates job number, part number, drawing revision, lot, quantity, location and ship status. Block three records the decision, the approver, the date and the customer notice reference, so the whole recall reads from top to bottom on one page.
Open a blank worksheet to printQuestions owners ask
How often should precision gauges be calibrated?
There is no single answer. Begin with the maker’s advice and your customer’s terms, then adjust from the as-found history of each gauge, stretching the interval after clean returns and cutting it after drift. Heavy use and harsh coolant shorten intervals.
What is an out of tolerance recall?
It is the step taken when a gauge fails its check: identify every part measured since the last good result and assess whether those parts can be trusted.
Can a spreadsheet run this programme?
For a small crib, yes. It struggles once measurements sit in separate files, because linking a gauge to jobs by hand is slow and easy to miss.
Who owns the calibration register?
Usually the metrology or quality supervisor. Each gauge should also have a named holder on the floor who answers the due alerts and reports any knock or drop the same shift.