The Engineering Change Log: ECO Control for Small Shops

In the sample quarter: changes caught at the design stage averaged $475. Caught in production: $2,142. Caught in the field — at a customer, in a truck, under warranty: $9,600. Twenty times the design-stage price. The two field ECOs cost more than the other six combined, and every one of them was an upstream gate that failed.

How it works

• The Change Log — every change numbered, reasoned, costed (engineering hours included — six hours of redraw belongs on the ECO, not in the ether), with stock disposition and status. The catch-point rollup runs itself
• The Gate — eight questions before any signature: where-used, stock disposition, supplier, docs and BOM, customer approval, effectivity (a serial or date break, written down — the one line that prevents two "correct" parts in the wild), tooling, and who verifies first articles
• The Discipline — one change one ECO, deviations flagged with expiry dates, the savings ledger that makes cost-reduction changes pay rent, the Friday review, and the postmortem that fixes the gate and not just the part

Built for

Machine and job shops · fabricators · hardware startups pre-PLM · millwork and cabinet shops · anyone whose drawings and reality have ever disagreed at a customer's site.

What you get

One .xlsx file, four tabs, instant download. Excel, Google Sheets, Apple Numbers, LibreOffice. No macros, no subscription. Not a PLM system — the discipline that survives buying one later.