Drawing & Model Revisions, do they match?

Just curious, How does you or your company handle drawing & model revisions?
A) drawing and model always identical B) drawing can change without changing model (missing dims, change notes,
etc...)
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Regards,
Kenneth
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For us, drawing and model are always identical.
For "real" changes (e.g--change a dim) we use whole number revisions (e.g.-- R2>>R3). For "cosmetic" changes (e.g.-add a missing dim to a print) we use decimal revs (e.g.--R2>>R2.1)
For a while, we tried using mixed Revs (e.g--dwg @ 2.1, part at 2) but found that it generated enough issues that we abandoned it. The minor extra paperwork to change them both is easily worth the aggravation and confusion it's saved us.
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Drawings have revisions, models do not. All drawings have a TIFF and IGES created at release with associated revision in the file name.

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Models and drawings always match and are at current rev. Old revs are saved only as PDFs.

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In our case, the revision of the sheet is the same as the part, because when you change the part, the sheet must be change and also the sheet indicates the revision of the part. So for all of these, we decided that sheet and part carry the same revision.

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150979.news.uni-berlin.de:

I've seen people do it both ways, and there are good reasons for doing it either way. When I implemented a PDM system, I opted for separate revs for model and drawing. The model will change many times before a drawing is made, and changes to the drawing may be independent of the model. We really didn't use the model for anything other than making the drawing and doing some FEA. We tracked the model rev, but didn't link it to the
People who do rapid prototypes or CNC from the model may feel the need for the drawing and the part to always have the same rev. The only real problem with this is that most PDM systems see the model and the drawing as being two separate (but related) documents, and each document has its own rev level.
One way around that might be to list the model rev in the drawing title block so from the drawing you will know that Rev B of the drawing relates to Rev E of the model. You might even give the model a different sort of rev designation, like numeric, to make sure that the drawing and model are not confused.
Remember also that some PDM systems (like PDMWorks) give you the ability to pull up referenced documents using the "as built" or "latest" revision of the model.
matt.
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We used to use Revision for the Part, and Version for the Drawing, both were indicated on the drawing and both were populated by custom properties in the model. This ensured when either one changed, you had to go back to the model to make the change. This made the model the master from an engineering point of view, even though the drawing was the master from a manufacturing point of view.
We soon dropped this, as is proved too confusing for certain members of the manufacturing team. Now the drawing is free to rev as often as it needs to be, and it does not have to match the model rev.
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Hi,
As virtually all our parts are produced by computer controlled machines reading the files directly in our case the model is always the master with the drawing produced as a Check or Reference. The drawing issue number will change whenever there is a change on the drawing, be it a 'real' change or 'cosmetic' change. The model gets a part number and issue number which is also 'engraved' on the part to identify it. In the drawing block the model part and issue number is shown automatically by the drawing template and updates whenever the model 'Save As' is changed so when viewing the drawing there is no doupt about the model part number and issue it relates to.. phew...
Hope this helps ...... Sonny

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Thanks to all. Your opinions are invaluable.
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