Drawing revision control: stop building from old drawings
Good revision control means every drawing has one released version at a time, a revision letter that changes whenever form, fit or function changes, a revision table that says what changed and why, and a single place where the floor and suppliers get files. Old revisions are marked obsolete or removed, never left in shared folders or printed copies.
Guilherme Rodrigues ItinoseUpdated 2 min read
Key takeaways
- One released revision per drawing, stored in one place.
- Change the revision whenever form, fit or function changes.
- The revision table explains what changed, who approved it and when.
- Mark or collect obsolete prints; the floor should not choose between versions.
- Model, drawing, DXF and STEP must share the same revision.
Scrap caused by an old drawing is one of the most expensive and most avoidable problems in manufacturing. The part was made perfectly, just to the wrong revision.
The four rules
- One released revision at a time. Drafts live elsewhere; only released files go to the floor and suppliers.
- Revise on any change to form, fit or function. If a part made to the old revision would not work, it is a new revision.
- Explain the change. The revision table on the drawing lists the letter, what changed, date and approver.
- Everything moves together. Model, drawing, DXF, STEP and BOM carry the same revision.
A simple setup for small teams
| Item | Simple rule |
|---|---|
| File name | PART-NUMBER_REV.pdf, e.g. 10452_C.pdf |
| Folders | WORK (drafts) and RELEASED (read-only) |
| Release log | Spreadsheet with part, revision, date, reason |
| Floor copies | Printed with revision and date, collected on change |
| Suppliers | Revision written on the purchase order |
When to move to PDM
When several designers edit the same assemblies, when files are copied to laptops or when audits ask for approval history, a PDM system with check-in/check-out and workflow saves more than it costs.
Our manufacturing documentation service delivers drawing sets with revision tables and release logs, and keeps them current through engineering changes.
When to outsource this
- Parts were made from outdated drawings more than once
- You are preparing for ISO 9001 or a customer audit
When not to
- A one-person shop where the designer is also the machinist
FAQ
Letters or numbers for revisions?
Either works if it is consistent. Many companies use numbers for drafts (01, 02) and letters for released revisions (A, B).
Do I need a PDM system?
Not on day one. A single controlled folder, a naming rule and a release log work for small teams; PDM pays off as people and files grow.
What counts as a revision?
Any change that affects form, fit, function or interchangeability. Cosmetic corrections can be noted but some companies do not re-revise for them.
How do suppliers know they have the latest?
Send drawings from the controlled source, include the revision in the file name and PO, and ask suppliers to quote the revision they used.
Send us one drawing
We return a review with issues found, suggested fixes and a fixed-price scope.
