Revision control for released drawings

Revision control is not version control

Software teams say version control and mean Git: every commit is kept, branches are cheap, and you can check out yesterday's file whenever you want. Hardware teams say revision control and mean something stricter. A drawing revision is a named, released state of an original — Rev A, Rev B — that manufacturing and the supplier are allowed to build. Drafts, markups, and "almost ready" PDFs are not revisions. They are work in process, and they should not leave the building.

In a CAD or PDM context the confusion is easy. SolidWorks, a vault, or a shared drive will happily keep twenty files named housing_final. The vault may even have versions. That is still not revision control if the shop cannot tell which file is the released original, or if a supplier was sent a copy from someone's desktop. Version history answers "what did we try?" Revision control answers "what is the current released drawing, and who is allowed to see it?"

Hardware revision control therefore needs three guarantees. First, drafts stay inside the tenant. You can iterate on a document without that file becoming the thing a CM quotes. Second, a release is an explicit act: this original is now the latest released revision. Third, anyone outside the company who needs the drawing sees only that released original — watermarked, not a download of whatever happened to be in the folder. If your process still depends on attaching a PDF to an email, you have version scatter, not revision control.

CAD-native PDM is one way to get there if every stakeholder lives in the vault. A small hardware team often does not. The mechanical engineer has CAD. Quality, purchasing, and the supplier do not. They need the released PDF on the same product record as the part, and they need the share path to refuse drafts. That is the hardware meaning of revision control, and it is why people search for it next to "drawing management" rather than next to Git.

Where-used still matters. A revision is useless if you cannot find the part it belongs to, or if last year's part number disappeared when you adopted the new tool. Keep-old numbers stay searchable so the drawing and the item can be found by the identifier the plant already uses.

The failure mode is familiar. Engineering iterates in CAD. Someone exports a PDF "for the supplier" before release. Purchasing forwards an older attachment because it was already in the thread. The shop builds the wrong housing. Revision control is the discipline that makes that path illegal: only a released original is selectable for Notify, the link and one-time code travel in separate emails, and the page the supplier sees is watermarked and not a download. Version control can keep every WIP file. It cannot, by itself, tell a contract manufacturer which one is current.

Released is the only thing that leaves the building

Teams looking for revision control, drawing management, or a SolidWorks PDM alternative usually need two guarantees: drafts stay inside, and the file you send is the released revision. Nereite PLM stores documents on the tenant, releases a revision, and allows external preview of that released PDF only.

External preview is watermarked (recipient and product context on the page). Internal preview for signed-in users is unstamped so you are not editing a stamped derivative. Download is not part of the share path.

Item master and where-used

Revision control is useless if you cannot find the part. Keep-old part numbers stay searchable. The BOM and the drawing sit on the same product record so a where-used question does not start in three systems.