Another Rev Question... and Notes (general vs. flag vs. revision) 1

[Superslinky]

Hey all,

Just finished up a project and shipped it complete with spelling errors, flag note errors, general note errors, etc, etc.

My question is. Are spelling corrections revision??? It sounds like it wouldn't be and I can't ever remember issuing a rev based on spelling..

We also had to go back and differentiate between general notes, flag notes and revision notes.

The process taken was to make a flag notes numbers in a square with a leader to the affected area and then the square was also surrounding the number in the notes list.

Revisions were left as a number surrounded by a triangle and then the triangle symbol added to our revision block.

Does anyone know about this stuff? I'd appriciate any insight that can be offered.

Thanks much.

 

[SteveMartin]

In my perfect world any time a released drawing gets changed in any way would be a revision. I like minor/major revisions for this sort of thing, with different approval procedures for each.

The reality in all the organizations I've been in has been that spelling errors & similar either get left the way they are at release time, or get quietly cleaned up without a revision. Generally this is because people do not want to deal with the overhead of the CO/ECO paperwork associated with formal revisions.

 

[KENAT]

1. Are spelling corrections a revision?

In a strict document control situations yes they are. Any change to the drawing should be a revision.

2. Differentiating between flag notes & rev symbols?

Per ASME Y14.35M-1997 only circles are used for revision symbols - however in practice I've seen other symbols and I'm not sure why they limit it to circles so can't get hung up on that. Also per that std where rev symbols may conflict with other symbols they may be omitted.

I'm not aware of anywhere in the standards that explicitly say they should be different. However, it should be commonsense. A drawing should be unambiguous. Using the same symbol for different things is asking for trouble.

Using the same symbol around the number in the note block as for the flag symbol is common practice, not sure if it's in a standard though.

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[ctopher]

I agree, any change would be a revision. I would use a minor revision.

Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion

 

[Superslinky]

I dug up our copy of ASME Y14.24-1999 and read the part where it cited the circle. What I gathered from is that you 'can' use a circle but not that is has to be a circle. I also read where it said symbols can't confict would really mean making my rev "circle" larger or smaller or something rediculous. I think I'm going to try to hang onto my triangle for now. With any luck the work I did to clear up the flag note/general note thing will be sufficiant and at the same time make the rev triangles more clear.

As far as "strict document control situations", I do have one indeed. I think here I'm going to write up an extensive ECO and cite that on the drawing. Exceptable you think?

For example: REV A (or should it be numerical?) Changed per ECOXYZ?

Thanks guys...

 

[Superslinky]

Minor vs major rev. Can you describe to me the difference or at least a procedure to handle each? I realize the difference between major and minor, but how would that reflect on our ECO or documentation? Thanks..

 

[KENAT]

Well of course the ECO should generally be listed on the drawing. Trying to think of any time it wouldn't be.

In aerospace we had to do 'is' - 'was' for any change in such detail that the change could be reversed.

For example:

Note 4 - "DIMENSIONS ARE IN INCHES" was "DEMINSIONS ARE IN INCHES"

Or similar. Maybe now that old copies can be kept digitally that's a bit over the top but I spent many hours writing detailed ECO's like that.

14.24 isn't the correct spec for revision indicators.

Have you tried SQUIRCLES?

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[ctopher]

A little info...
thread404-122631

Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion

 

[SteveMartin]

Major vs. minor as regards documentation is mostly a matter of quantity/depth of approval/review required, and may also involve different method or scope of downstream notification of the change(s). Your documentation would have to define what type of changes could classify as either, and set up different approval procedures for each.

Ideally a minor rev would be a very small/quick approval process, probably involving a relatively small number of people - certainly including the responsible engineer, others would be somewhat dependant on organization structure. A major rev would be a longer and more thorough review, and include most if not all departments in the organization.

 

[KENAT]

Almost by definition a true rev is minor - since if interchangeability of a part, the need to track it... is affected then it requires a new part number chased up through the pack until interchangeability is achieved. Per ASME Y14.100

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[MintJulep]

I tend to get very upset with vendors when I find copies of the same revision document that are not identical.

I tend to start asking questions like:

"How can I trust anything you send me?"

"How can I trust that you are building to the same prints you sent for review?"

"Show me in your documentation procedures where it says that it's ok to have this situation?"

"If you can't follow your documentation procedure how can I trust you to follow any of your procedures?"

 

[drawoh]

Superslinky,

I would say that any change to a production drawing is a revision. In the revision block, you can state that you corrected spelling, and that there is no change to the as-fabricated part

I do not recognize a difference between major and minor revisions on a fabricated part. For software, it makes sense. You fixed some bugs. You did not add or delete features. At a product (as opposed to assembly) level, you fixed some details, without adding or deleting features.

If you update your revision_A, it does not matter to anyone if you change it to A.1 or to_B. No process is affected. You should not change form, fit or function of your part. Your fabricator must examine your drawing to see what you changed. Production must work out whether or not the old parts in stock can be used as-is.

JHG

 

[CheckerHater]

Some REALLY long time ago I've heard the following reasoning:

The most important quality for the revision record is to be reversible: "dim was 12 mm, q'ty was 3," etc., so in perfect world it should be possible to reverse part to its original state.
Sinse there is no legitimate need to reverse part back to the wrong spelling, there is no need to attach revision record to spelling corrections.

Obviously, this is one of many ways to look at it.

 

[PeterStock]

Where I am now we go by the x.xxx WAS y.yyy methodolgy for the most part, but do word some things a bit looser than I would have back on the drawing board. But at previous companies, we did a lot of REVISED PER ECO 12345. If you create an eco document, why not make use of it? The ECO should be capable of recreating the previous rev in the event that file, paper drawing or whatever is not available.

Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services

http://www.infotechpr.net

 

[PeterStock]

At a company a number of years ago we were doing drawings for a version of our product to be delivered to the Navy. These were on NAVSEA formats. We noticed that in the supplemental signature block, the first word was spelled SUPPPLEMENTAL. We left well enough alone, we did not what to go through the effort to get all the signatures to revise the entire package so we left it like it was. But when the project was over, we corrected the CAD formats for later use.

Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services

http://www.infotechpr.net

 

[dgallup]

Any change triggers a revision level change around here. However, we have a greatly simplified procedure to approve something that is just an obvious error correction like a misspelled word. In effect, I can get a corrected version all the way through our otherwise sluggish document control system within a day.

 

[ewh]

ASME Y14.35M-1997 refers to a revision as being "Changes made to an original drawing or associated document after authorization release which requires the revision level to be advanced. (emphasis mine) It does not address what type of changes require such a revision advance.

I don't know which standard this was based on, but per the Global DRM 5th edition, para 18.4.8 Undocumented Changes "The following drawing corrections or additions may be made without recording on an ADCN or DCN: similar to data, required approval signatures (except checked), weight information, misspelled words, missing arrowheads, next assembly. Such changes are normally made when incorporating other authorized changes, and will be checked by an authorized checker."

Global has a pretty good reputation at following the standards closely, and I would tend to trust them before I would others (such as Genium) for this type of detail. Granted, the issue I have to refer to was printed back in '85, and may indeed be obsolete.

While I no longer have access to ASME Y14.100 or most of the others, I would not be surprised to find such an exemption somewhere buried in those standards.



"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[ewh]

"...and will be checked by an authorized checker."

I know, I know... I still sometimes visit fantasy land.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[Superslinky]

All good info guys and thank you for your responses. Dont you wish everything could be this cut and dry?! :0

Sounds like my plan of action is to just do the rev, call it rev "a", refer it to ECO12345 and move on. Maybe I'll even make mention of the spelling in the ECO... By the way, does anyone have any insight as to whether a rev is alpha or numeric or does it matter?

 

[SeasonLee]

Per ASME Y14.35M-1997 Revision of Engineering Drawings and Associated Documents, section 5.1 Revision Letters states “Upper case letters shall be used in sequence beginning with A and omitting letters I, O, Q, S, X and Z…..”

SeasonLee