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How do you do revision control without PDM?

Larry Wu, CEO, Kyumi · Last updated October 12, 2026

Without PDM, revision control comes down to three habits: one owner who releases files, a fixed naming rule with the part number and revision, and a released folder that only holds the current revision. It works for a team with one or two CAD owners, and starts to break when several people edit shared assemblies.

What PDM actually does for you

PDM's core jobs are check-in and check-out, so two people don't overwrite each other, and a revision history for each file (Duro). Without it, you replace those jobs with rules people follow. That is fine as long as the rules are short.

A routine that works on a small team

1. Pick one release owner

On a team with one or two CAD owners, one of them releases drawings. Everyone else can work in CAD, but only the release owner moves a file into the released folder and bumps the revision.

2. Use a fixed folder structure

/100-0234 Motor bracket/
  /wip/          working files, anyone with CAD can edit
  /released/     current revision only: SLDPRT, SLDDRW, PDF, STEP
  /_obsolete/    every superseded revision, never deleted

Suppliers and reviewers only ever get files from /released/.

3. Decide where the revision lives

There are two common approaches, and forum threads show teams using both (Eng-Tips):

Approach How it works Good for Breaks when
Revision in the file name (100-0234_RevC.sldprt) Copy the file to a new name for each revision Parts and drawings sent out often Assemblies still point to the old file name and must be updated by hand
Revision in file properties only (100-0234.sldprt, property Rev = C) Same file name forever, old revision copied to _obsolete Parts used in many assemblies Someone opens the obsolete copy by mistake
Revisions as configurations One file, a configuration per revision Small stopgap Changes made in the wrong configuration; file size grows

One SolidWorks forum poster describes copying and renaming the part and drawing for each revision, and notes that multi-level assemblies then have to be updated by hand (SOLIDWORKS forum). Another notes that Pack and Go for each new assembly revision falls apart when subassemblies are revised separately (SOLIDWORKS forum).

A rule from drawing practice is worth following either way: keep the drawing revision out of the part number itself. Forum replies cite ASME Y14.100 for this (Eng-Tips).

For most teams under 10 CAD users, keeping the file name fixed and the revision in a custom property linked to the title block causes the fewest broken references.

Whichever you choose, keep one rule across the team: native CAD files keep a fixed name, and every exported PDF and STEP carries the part number and revision in its file name, for example 100-0234_RevC.pdf.

4. Number prototypes, letter releases

A widespread convention is numbered revisions (1, 2, 3) during prototyping and letters (A, B, C) once a drawing is released to production (Eng-Tips). ASME Y14.35 covers how revisions are identified; check it, or your customer's drawing requirements, before settling on numbers or letters (NDIA).

5. Write the reason in the revision block

Every revision gets a line: what changed, why, who approved it, and the date. "Moved M4 holes 2 mm outboard to clear J3 connector" is a revision note. "Updated per review" is not.

6. Lock files socially

Without check-out, agree on a simple rule: post in the team channel before opening a shared assembly for edit, and again when you close it. It sounds crude and it prevents most overwrites.

Where a manual routine breaks

A manual routine only works if everyone follows it every time. One rushed release, one file saved to the wrong folder, and the released folder stops being the truth. The reason for a change also shrinks: it ends up as a few words in a check-in comment or a revision block, and the test result or supplier call behind it stays somewhere else. And people outside CAD, like electrical, firmware and manufacturing, still review from PDF and STEP exports, so their comments land in email instead of next to the revision.

What about Git?

Some teams store SolidWorks files in Git with Git LFS. A FIRST robotics team on Chief Delphi describes using Git with GitHub Desktop for SolidWorks files (Chief Delphi). Git gives you history and, with LFS, file locking, but it cannot merge or diff SLDPRT files, so two people editing the same part still lose work (SOLIDWORKS forum).

When it is time for PDM

PDM Standard is included with SolidWorks Professional and Premium (Javelin); see PDM vs PLM: which does a small hardware team need? for what it includes and its limits.

Signs you have outgrown a manual system:

  • More than two people regularly edit the same assemblies.
  • Someone has overwritten someone else's work in the last quarter.
  • You can't answer "which revision did we ship in March?" in under five minutes.
  • A supplier has built an old revision.

FAQ

Is PDM Standard included with SolidWorks Professional?

Yes, with SolidWorks Professional and Premium. It still needs a server running Microsoft SQL Server Express, and licensing changes, so confirm with your reseller.

Should the revision letter go in the file name?

It is common for files sent outside the team, but it breaks assembly references when revisions change. Many teams keep the file name fixed and put the revision in a property linked to the title block.

Can I use Git for SolidWorks files?

Yes, for history and backup, and Git LFS adds file locking. Git cannot merge or diff SolidWorks files, so it does not stop two people from editing the same part.

Rev A or Rev 1 for prototype drawings?

A common convention is numbers during prototyping and letters after release to production. Check ASME Y14.35 or your customer's drawing requirements, then pick a rule and write it down.

Related questions

Sources

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