We keep every revision, and we keep plt files of every revision.
xxxxx/E or m /(code)001 rev A etc...
The plt's are for record purposes, and they can be converted into pdf or dwf or jpg etc. so is very handy.
The dwg files are kept because we are paraniod about engineers wanting to go back 3 revisions as the client has changed his mind.
Supersed drawinsg are moved into a superseded folder, if we are running out server space we have a rule that we can delet or move onto archive cd old revisions.
