revision changes on dwgs?

Probably a dumb question but....
Do most of you bump the revision only after the product has been manufactured and a change occurs. So before the product is manuf any changes that occur would not require a revision change.
thanks

The design stage may be complex enough that some sort of drawing revision control is necessary. An opeation can define 'design' stage drawings and 'final' or 'as shipped' drawing controls.

Hi
We usually use rev 0 to be the 'design copy' which we be up revved as required O1,O2 etc

When formally issued to the customer that will be Rev A and will be up revved A1 A2 etc then when ready for construction it will be Rev B so B1 B2 and finally As Built will be Rev C

ok thanks for the info.

If a copy of the drawing had left the engineering department I always issued a new revision number. That included copies to suppliers, customers, even internal review by purchasing or QC and such. That included electronic transfer as well as hard copy.

Numbers are cheap. Two people unknowingly working from different drawings can be very expensive.

Every revision is recorded and saved in my establishment.

We use alpha (A,B,C ...) for design revisions, and numeric for construction, starting with 0 for as built
Any system is fine but you definitely need to track revisions during design phase

My CAD changes "date" automatically when print. I can't forget it!
Each pages have their own file with date as MicroSoft have planed.

i use rev0.x.x until leaving workshop i go to rev1.0.0
and yes every change has a own number, otherwise impossible to follow what changed. In description is the change and on the drawing i try to put the version number close to the change. this way you can see why, when,who,what,where,whisky(oops it is friday afternoon)

I tend towards not changing the revision number of a drawing (or program) until or unless I have released it beyond the bounds of my computer.

Once there is a chance that there different versions of the file in existence, you need to start revision drawings just to keep track of who has what info, and whether they are current or not.

I use ACADE and its title block update utility. While I'm making the original drafts I don't fill in the title blocks. Just before I put it on the company intranet to begin the design review process I run the title block update utility. From that point on the revision tracking process is followed. Minor revisions are shown with a number after the letter, A.1, A.2, etc, major revisions and milestones will change the letter but the letter doesn't mean anything in particular - that is spelled out in the revision information section of the title block. Release for design review, quote, build, as built, etc are all milestones that may or may not be a part of a project. Some final release sets might end up at Rev D, while others might be at Rev K. We don't use Rev letters I, L or O to avoid confusion with numbers 0 and 1.