ASME Y14.41-2003 & Adobe PDF....

[dmech]

Hello Forum,

I don't enjoy the circular process of turning my 2D concept sketches into 3D CAD geometry, to only revert it back to a 2D engineering drawings...seems wasteful. I don't see the point in entering data twice (i.e. once in during 3D CAD and again in the 2D drawing). I don't like having to update changes in two places. Hence, I'm very excited about moving to the new ASME Y14.41-2003 standard.

What does the forum think about using Adobe 3D as a standard exchange format for ASME Y14.41-2003 engineering control data?

The reader is free (i.e. Vendors don't have to pay for the ability to view 3D design information). Vendors can measure , section, and study the part to their hearts desire. And lastly, they can use the 3D PDF data to export a suitable IGES or STEP file for CAM import (we only need to send the vendor one small file) In addition, it lends to easy revision management using current PDM solutions...and the list goes on. Anyone agree?

Check out the feature demo:

http://www.adobe.com/products/acrobat3d/

It seems like the biggest hurdle is affordable CMM inspection equipment. Here's to 2D drawingless world!

P.S. And no, I don't work for Adobe or its subsidiaries.

 

[fcsuper]

I guess a side note is "What software are you using that requires you to enter data twice?"

But to answer your question, it sounds like you answered your own question!

Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group

 

[ewh]

I'm also excited about this evolution. While I haven't any experience using Adobe 3D, I have recieved customer files in their native format using this standard, and it seems to be the wave of the future.
I think it will be awhile though before it is fully accepted, as their are too many old school fabricators who don't seem to want to fool with it. The same thing was said of CAD when it was first being used, and look where we are today.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[KENAT]

There have been threads on here about MBD generally before, it's almost certainly the way of the future.

The question is just how far of is that future.

For some sectors it's here, and has been for a while.

For others it seems it's still a ways off.

I've looked into it a little and for my organization the leap to MBD is probably a ways off for various reasons.

Acrobat 3D is one option but I've also heard JT being pushed hard as well.

KENAT, probably the least qualified checker you'll ever meet...

 

[dmech]

Thanks for the reply all. I agree that another large hurdle is getting job shop guys on board. In addition to inexpensive ways to inspect against the 3D file.

One note regarding the job shop. I've spent days working on multi sheet drawings, twenty view drawings, with detailed 2D GD&T. I pass it off the the vendor to have him/her say "Theres to many dimension, just send an IGES and point out the critical tolerances."

Needless to say...some job shops are ready, but maybe not ready for a new standard they must formally learn.

FYI: Solidworks 2007

 

[KENAT]

dmech, I don't know about your system but for our CAD if you know what you're doing then generating the drawing from the CAD model isn't too time-consuming.

Sure calculating the required tolerances, tolerance scheme etc takes time but...

With MBD surely you're just moving that effort from in the drawing to in the model.

Remember, a drawing (and hence presumably MBD) isn't just for manufacturing. It's for inspection too, it defines what you need/will accept.

If people are just using MBD because they think it means the don't need to worry about properly designing/detailing things, such as tolerances, then I see that as probably a bad thing.

thread1103-182896 thread1103-182500

KENAT, probably the least qualified checker you'll ever meet...

 

[ewh]

Right you are, KENAT. Datums and tolerance schemes will have to be defined, regardless of the format the information is presented in. I don't see that going away any time soon, if ever.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[fcsuper]

dmech, your comment is just scary to me. In no way should a vendor rely on "critical dimensions", never ever never. The product should be fully defined regardless of method of documentation. Yes, the drawing can have just a few dims on it with appropriate callouts, but all unidentified dims still have to be toleranced in some way. ASME Y14.41-2003 para 3.1.1 says that GeoTols are preferred, but that direct dimensioning is allowed, all per ASME Y14.5M of course.

And to add to KENAT's comment, the drawing is an actual contract by its own right. I've not seen similar consideration given to a solid model. Reliance on solid models only suggests even higher reliance on P.O.'s to set the requirements of the product as being per the model. Any one else have a comment about this point?

Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group

 

[ctopher]

I agree with the others 100%.

The comment "Theres to many dimension, just send an IGES and point out the critical tolerances" is pure ignorance and laziness.

Chris
SolidWorks/PDMWorks 08 2.0
AutoCAD 06/08
ctopher's home (updated 10-07-07)

 

[MadMango]

That's when you say, "You know what, we are using a different vendor. Thank you."

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[ewh]

Matt,
As to putting a higher reliance on PO's, this isn't necessarily so. The same toleranceing data that was present on a drawing would now be present in the model file, NOT just a solid body alone. CAD packages are evolving so that any GD&T notation will be tied to the model. Pick the notation, and the associated area of the solid will also highlight, and visa-versa. Notations will be oriented to the screen regardless of how you rotate the solid. There are packages out there now that will tell you if the GD&T that you want to use is valid or a pipe dream.
One downside will be in achieving the discipline necessary to segregate all of this info so that it is easily readable and retrievable, but that can be overcome, as it has with ever more complex solid models.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[KENAT]

ewh, you have more familiarity than me but I was under the impression that places that take MBD seriously have some kind of rules of use that amongst other things may define default tolerances. That or the data is embedded in the model.

I seem to remember someone saying they made screen shots of the PMI on the model. This just plain scares me, if you're going to do that surely a minimal drawing is better so you have config control over it.

As to

"Theres to many dimension, just send an IGES and point out the critical tolerances."

A few thoughts -

1. If they want to machine against the model fine. If they want to inspect against the model on CMM to find variation from the model OK. However, in your case the tolerance information on the drawing defines what this variation may be. If no one else inspection will need this. At places I've worked vendors are usually expected to 100% inspect at least the first article to prove their process etc. This report is then usually verified by the customers QA. Your scenario doesn't seem to support this.

2. I've seen some really bad, really complex drawings that have so much information displayed so poorly, especially if GD&T isn't used correctly, that I can imagine they might provoke that response. However, once redrawn by someone who knows what they're doing they're usually a lot simpler. Not saying this was the case with yours but I have seen it.

3. Assuming (2) above isn't the case then yes, you need to look at an alternative vendor. That is if you care about quality.


KENAT, probably the least qualified checker you'll ever meet...

 

[ewh]

KENAT<
As I understand it per 14.41, all of the tolerancing required to make an acceptable part has to be in the model file, on a drawing, or a combination of both. The rules for GD&T still apply. I have seen simplified drawings where only the datums and critical dimensions are shown, with a general note specifying a profile tolerance for the undimensioned features (which is how we document many of our parts).
As for configuration control, electronic approval for drawings has been around for years. Electronic approval for model files is no different. If someone prints a screenshot of PMI on a released model, it is really no different than doing the same of a released drawing. Once printed by unauthorized parties, it is considered "uncontrolled" and it's use can quickly get someone terminated. As with the type of configuration control that we are used to seeing with paper drawings, some discipline will be required.
I share your concerns though. The key is configuration CONTROL.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[fcsuper]

EWH, also, I think you misunderstood my comment about the solid model. I've not seen any indication that would suggest that a solid model is by itself a legal document, regardless of how it is detailed and dimensioned. Have anyone seen this issue addressed anywhere?



Matt Lorono
CAD Engineer/ECN Analyst
Silicon Valley, CA
Lorono's SolidWorks Resources
Co-moderator of Solidworks Yahoo! Group
and Mechnical.Engineering Yahoo! Group

 

[KENAT]

I'd guess that if an electronic copy of a drawing (e.g. scanned and emailed or pdf and ftp'd) can be a legal doc why not a model with all the relevant information in it, be it meta data or otherwise?

KENAT, probably the least qualified checker you'll ever meet...

 

[ewh]

Sorry Matt, I did misunderstand. I have seen rather verbose disclaimers and rights notices embedded in models (by major companies), so there must be something to it being a legal "document".

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[ctopher]

With the major aerospace companies that I work with, the model is a legal document, but not by itself. There still needs to be a drawing associated with it for inspection/installation purposes by both parties.

Chris
SolidWorks/PDMWorks 08 2.0
AutoCAD 06/08
ctopher's home (updated 10-07-07)

 

[ewh]

You are right, Chris. As it is today, one of our major customers (big plane company in the NW) includes "A" size dwgs with some general notes and an iso view of the part. The only reason that I can see for this is to ease any config control problems, as there really isn't enough data on them to do much with. All of the pertinent data to make the part is in the model file.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[dgallup]

To get back to the original post, I've tried using Adobe 3D with Pro/Engineer WF2.0 and it failed miserably. Pro/Engineer has a rather unique implementation of family table based part & assemblies that allow a single generic model to have tens or hundreds (or thousands) of unique instances. We make heavy use of this capability as it is very powerful and saves a great deal of time. Adobe 3D is incapable of understanding this data structure and results in either missing or hopelessly corrupt geometry. There is another way to create the Adobe 3D file where it essentially does a screen capture while the CAD system is running. This correctly read the geometry but lost all the layers, part names, assembly structure, named views, etc.

Adobe 3D may work better with other systems or for simpler objects but it has a long way to go before we will consider it useful, let alone a replacement for drawings.

I for one don't see how the model alone can ever convey as much information as drawings. Trying to shown all the dimensions, GD&T, material specs, notes, copyright, etc. on a model makes it hopelessly cluttered for anything more complex than a box. Using multiple layers to turn things on & off means that people could easily overlook vital information that is not visible. How do you show assembly stages, alternate configurations & many other common drawing constructs in a single model?

 

[MadMango]

dgallupI don't think Y14.41 will ever be the catch-all for every instance that you have listed. I think a lot of 2D information will remain and as a whole, we will see manufacturing data in the model, and inspection/assembly criteria on the prints.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of Eng-Tips Forums?