Standard procedures on drawing revisions

I'm curious how all of you out there handle your drawing revision system. Ours is dictated in letter format meaning in the 1st round of approvals all sheets are status "A". After that ONLY sheets which are revised move up to the next letter, so some sheets throughout the project duration may not change therefore remain at "A" status. The last sheet of a drawing set is always our revision control sheet which shows what sheets have changed as well as a brief description of that change.

The reason I'm bringing this up is we have a customer that doesn't like our system and wants all sheets to have the same revision status even if some sheets didn't change. To me this doesn't make sense and may cause our shop guys to be confused therefore leading to other issues. So in essence, should a company change it's drawing process to pacify one customer? If so wouldn't that mean constantly changing your drawing standards to suit everybody? Would like to hear some input on this, see attached as an example of our drawings for reference.

Comments

  • I agree with you and would suggest that you sit down with the client and explain what he is asking falls outside the norm and unless he can give you a good explanation as to why his idea makes more sense you'll be sticking with your system. Ask him specifically, "What advantages does your revision system offer?"

  • I agree it's a bad idea.
    In our building industry it's typical to mark each sheet A B C independently, then 0 for issue for construction, then 1 2 3...
    Larger projects might have say 50 HVAC dwgs - they will get pretty tired of printing the set because one ceiling grille changed.
    If you can't win, you might mark the rev 'no change'.

  • From the customer's perspective, their configuration management is much easier if every successive baseline is marked on each sheet, independent of the underlying revision. When I (playing the roll of Mr. Customer) pick up a drawing sheet, I want to know if it's associated with the current production lot or the one we ran last September. I don't care whether it's your rev 2 or 12. Trying to keep track of which individual sheet revs were part of which configuration is, for me (still roll playing), a giant pain in the ass and something which I'd much rather that Mr. Vendor handled.

    My suggestion would be to add a separate block on each sheet -- maybe split your existing Rev block -- which gets bumped. You'll need to agree on how to handle intermediate builds, since going from baseline C to D could involve multiple individual sheet changes over some period of time. "D (preliminary)" perhaps. All done with variables, of course, so it's only necessary to change it in one place.

  • I don't really have a strong opinion, since my company takes a different approach. Perhaps it varies by industry. We make large industrial refrigeration chambers, and sometimes act as general contractor for a facility remodeling.
    Most of the time we are exchanging PDFs with the customer, and not printing out. We tend to create each file that is released changed to be a revision, and append the date on the file name. So, if a drawing file has multiple sheets in it. Individual sheets will have their own latest revision date on it.

    However, drawings submitted to the local permitting office are involved, those are always hard copies, and are always released as a set. The entire set has one revision letter. But, there are only maybe one or two such revisions in the entire project. Nothing is produced by an older revision. If there were to be a change to the actual objects we manufacture during the course of the project, the object is physically changed to agree with the current version. So, in theory, the latest set of drawings is kept in agreement with what physically exists.

    -Joe

  • If you are drawing to the ASME Y14.24, Y14.34M or Y14.35M standard then the recommended method for handling revisions is clearly outlined in the ASME Y14.100 Standard entitled "Engineering Drawing Practices".

  • Tim Neumann
    edited June 2017

    I understand from a customer's perspective it can get confusing but for the vendor to change it's drawing "m.o." to please every customer that
    voices displeasure seems unreasonable, as they all have differing opinions. The issue for us is our shop workers are in tune with our revision practices and if we go about changing them frequently them it would only serve to cause confusion and hence slow production down. For the most part it's the large engineering companies we deal with that bring up this issue, because unlike us smaller outfits they have an entire workforce overseeing document control where it may be their job to "strain at a gnat to swallow a camel".

    My company only has (2) CAD positions and I fill one of them in addition doing project engineering so we're time strapped as it is. The system we came up with is simple and convenient to run with and ironically seems to be in line with ASME Y14.35 - correct me if I'm wrong. In the end we've offered to send the customer the actual dwg files so they can edit to their satisfaction, assuming of course they have the program to do it.

    Thank you all for the input, very interesting to see how others handle these issues!

  • How about if you paste a note onto any sheet that hasn't been revised, saying "NO CHANGES THIS SHEET FOR REVISION C"? Maybe with a revision cloud around it -- assuming that you use revision clouds on the sheets that have changed. And put it on the revision C layer so that it goes away automatically when you issue revision D. Wouldn't that note solve your objection and also please the customer, all with very little effort?

  • Tim: You are doing it the right way.

  • @Anthony Apostolaros said:
    How about if you paste a note onto any sheet that hasn't been revised, saying "NO CHANGES THIS SHEET FOR REVISION C"? Maybe with a revision cloud around it -- assuming that you use revision clouds on the sheets that have changed. And put it on the revision C layer so that it goes away automatically when you issue revision D. Wouldn't that note solve your objection and also please the customer, all with very little effort?

    Good idea Anthony, will consider that if this comes up again.

  • Tim, I'm going to start doing that as standard procedure. Thanks for getting me thinking about this.

    I won't print the unrevised sheets, unless someone asks for it, but it'll be good to have the unrevised sheets clearly marked in the cad file. And I'll be able to make a full PDF file each time a revision is issued, and this note will prevent any confusion about what's included in the revision.

    I think I can write a lisp function that will do a whole file at once. It'll prompt for a revision number, insert that number into the note and into the layer name, and then cycle through all layout tabs in the file, pasting the note in the appropriate spot on any layout that doesn't already have something on layer RevC.

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