We go one step further. Instead of a sub-directory, we simply rename the obsolete files using the extension (pdf in this case) for the revision (e.g. Rev 1 of a drawing would be renamed to name.001)
In this manner, it keeps pesky eyes from printing out of rev drawings. Most don't know what the .001, .002 etc.. extension stands for, and it won't open either just by clicking on it, but the CAD folks will know and it is pretty easy to rename the file if you need to print out an out of rev drawing.
Believe me, we've had our share of Purchasing, Marketing, and Production personnel wanting to get their hands on drawings and if pressed, will take anything even if it is out of rev. So, by renaming the old rev's extension, we have solved that problem, especially since most filter for pdf file types. The .001's ect won't even show.
Also, all the files are kept in the same folder so it makes it easier on those that use the files day in and day out. So if a part has say 5 or 6 revisions, it is rather easy to find the old rev rather quickly since all the files are kept in the same folders.
Just another way to scratch your itch I guess.
John Gusic
CAD Supervisor, Atlas Copco Compressors Inc
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