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--- consulting:the_consulting_technical_designer_and_manufacturing [2020/01/02 22:24] – [Separation of concerns] mithat
+++ consulting:the_consulting_technical_designer_and_manufacturing [2020/11/25 19:26] (current) – [Fixed versus live data] mithat
@@ Line 9: / Line 9: @@
 ===== Separation of concerns =====
-The manufacturer owns manufacturing.
+The designer takes responsibility for their design, and the manufacturer owns manufacturing. This means the manufacturer takes responsibility for managing the documents they need for manufacturing.
-The designer takes responsibility for their design, and the manufacturer takes responsibility for manufacturing. This means the manufacturer needs to take responsibility for managing the documents needed for manufacturing.
+Don't expect the design engineer to hang onto production files that are no longer relevant from a design perspective once they have conveyed them to you. Don't expect them to be able to regenerate the production files either. Assuming they have held on to the original source files, the software they used may have gone through several updates by the time you make the request, so there's no guarantee regarding how the new files will be regenerated. And since there is no guarantee regarding how the new files will be regenerated, they will need to be verified through another round of testing proto builds, even if nothing actually (or was supposed to have) changed.
-Don't expect the design engineer to hang onto files that are no longer relevant from a design perspective (i.e., the production files you are using) once they have conveyed them to you. Don't expect them to be able to regenerate the production files either. Assuming they have held on to the original source files, the software they used may have gone through several updates by the time you make the request, so there's no guarantee regarding how the new files will be regenerated. And since there is no guarantee regarding how the new files will be regenerated, they will need to be verified through another round of testing proto builds, even if nothing actually (or was supposed to have) changed.
+===== Final versus live data =====
-Owning manufacturing also means being able to distinguish between a design version's //fixed// data and its //live// data. Fixed data are things that will never change throughout the life of a given design version, like Gerber files. Live data are things that might change, like build notes, which should see a process of continual refinement, or a BOM, where one generic part may be swapped out for another depending on what's available at the time of manufacturing.
+Owning manufacturing also means being able to distinguish between a design version's //final// data and its //live// data. Final data are things that will never change throughout the life of a given design version, like Gerber files. Live data are things that might change, like build notes, which should see a process of continual refinement, or a BOM, where one generic part may be swapped out for another depending on what's available at the time of manufacturing.
-If you think the only thing that needs to change in a design is live data (e.g., the BOM) and it requires a design engineer's input, then you will need to decide whether it makes more sense to have them operate only on the live data //that you provide them// or have them regenerate everything, then re-test and re-prototype, and re-version the design. A good design engineer will try to make things happen with just a BOM or other live data fix if it's possible.
+If you think the only thing that needs to change in a design is live data (e.g., the BOM) and it requires a design engineer's input, then you and the design engineer will need to decide whether it makes more sense to have them operate only on the live data or to regenerate everything, then re-test and re-prototype, and re-version the design.
-===== More succinctly: two don'ts =====
+===== Two succinct don'ts =====
-Do not assume that the consulting design engineer will maintain a history of manufacturing files for you. If maintaining a history of manufacturing files is something you expect your consultant to do, expect to have to pay for the service. Reliable, traceable archiving isn't free, easy, or fun. It's work, and not the sort the design engineer wants to do. Especially when, as is so often the case, they are being paid a fraction of what they would be getting if they were a staff engineer someplace.
+The above can be distilled down to two succinct don'ts:
-Under no circumstances should you ask the design engineer to just regenerate what they sent you before because you either lost those documents or you can't be bothered to dig them up. Regenerating files the designer has previously vetted requires vetting them all over again. In most cases this means a full round of prototype building. Any designer worth anything will //not// release to manufacturing anything that has not been properly vetted. It's their ass on the line if something somehow got messed up in the regeneration.
+Don't assume that the consulting design engineer will maintain a history of manufacturing files for you. If maintaining a history of manufacturing files is something you expect your consultant to do, expect to have to pay for the service. Reliable, traceable archiving isn't free, easy, or fun. It's work, and not the sort the design engineer wants to do.
+Don't ask the design engineer to just regenerate the production documents they sent you before because you either lost them or don't want to dig them up. Regenerating files that have been previously vetted requires vetting them all over again. In most cases this means a full round of testing and prototype building. A good  designer will //not// release to manufacturing anything that has not been properly vetted. It's their ass on the line if something somehow gets messed up in the regeneration.