Validating 3D models from 2D drawings
Validating 3D models from 2D drawings
(OP)
We recently switched from Autocad to Solidworks. We have a sister company in India that is going to convert the majority of our 2D drawings to 3D models as well as recreate the drawings. The problem I am having is finding relevant information on how to validate all of the data coming to us from India. Does anyone have knowledge in this area? I could use all of the help I can get! *girl smiles.





RE: Validating 3D models from 2D drawings
Just for example: let assume a pneumatic or hydraulic manifold with many drill passes for high and low pressure fluids. One mistake in the depth of a drill can connect high pressure line to low pressure line or return line and you can throw away hundred thousand of US dollar. This is not a dream this was actually happened in a company I use to work for when shortcut was made in the process of drawing replacement.
RE: Validating 3D models from 2D drawings
RE: Validating 3D models from 2D drawings
RE: Validating 3D models from 2D drawings
I was involved with a switch from AutoCAD to SolidWorks at a previous company. After discussing the details and pitfalls of the move, it was decided that all new products would use SolidWorks, while all existing products stayed in AutoCAD until an engineering change was needed. During a change the conversion to SolidWorks was made and verified.
"Art without engineering is dreaming; Engineering without art is calculating."
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RE: Validating 3D models from 2D drawings
If you can't trust that India will recreate the drawings 100% then I would require a 100% check of all drawings to verify correct dimension/tolerances/notes/materials,etc...
Like Israelkk said..1 simple mistake and you can literally throw all your money saved by outsourcing the work right down the drain with the bad parts.
RE: Validating 3D models from 2D drawings
RE: Validating 3D models from 2D drawings
Actually, there may not be any need for new drawings unless some different information is needed that SolidWorks can represent better. The technical data should not change. Don't let the somebody all geeked up on SolidWorks try to claim that it generates a better drawing. It's a piece of paper with lines and words on it. SolidWorks' funtionality to generate new drawings and views might come into play on new parts or changes, but unless those features are needed now, the critical thing is to ensure that the 3D models are correct to your existing designs. The easiest way to do that is to have SolidWorks' outputted drawings exactly match the existing ones.
RE: Validating 3D models from 2D drawings
Remodeling your current 2D AutoCAD drawings in SolidWorks sounds to me like a good way to train your people in-house on SolidWorks. I think you have wasted an opportunity here.
I suggest good, old fashioned drawing checking. Get a blue highlighter and check each drawing view by view and dimension by dimension. An organized person should be able to do this quickly.
If you were to do this in-house, your SolidWorks drafter would be able to flag any drawings that looked weird or inconsistent, and you would be able to fix any mistakes you spotted.
RE: Validating 3D models from 2D drawings
"Art without engineering is dreaming; Engineering without art is calculating."
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RE: Validating 3D models from 2D drawings
With over 12K drawings to be converted as well as 50-75 new models monthly, our guys are getting a ton of training. Even the CNC programming guys are responsible for converting some of the drawings to models so they can apply what they learned in training to our real life applications. These replies are tremendously helpful! I am glad I found this forum.
RE: Validating 3D models from 2D drawings
Just in training class, we have found several drawings to either be over dimensioned or under dimensioned. Luckily, we have one of the engineers from India embedded with us for a few months during the early phase so he is helping us determine what issues should be dealt with accordingly. We are seeing minor mistakes being duplicated so deciding what to do with them will be carried across systematically.
This experience is definitely one that I will carry with me for a very long time (not to mention added to my resume...*girl smiles).
RE: Validating 3D models from 2D drawings
We did something similar at previous employer, moving 2D drawings into Pro E and it was a complete ball of chalk. Got contractors into help with schedule so the learning aspect was minimal. Pro E just couldn't do a lot of stuff the way hand drawn 2D did so changes were forced. Went something like 3X over budget or the like and introduced new errors to the pack, this for something that has been in production for 20+ years.
We also did some selected 'high value' items from 2D into Solid Edge here, but to compound things we also tidied the drawings, because frankly they sucked and couldn't just be sent to any competent shop.
As well as the 'mistakes' you mention, there may be a few things SW just doesn't do like the old 2D package and so you can't get a 100% match.
Assuming you aren't incorporating any design changes, tidying up of drawings or the like then I'd suggest 100% checking by a dedicated, qualified checker, of the new SW print against the old 2D print may be sufficient.
If you aren't changing dimensioning schemes, or making changes, then the need to actually make hardware off of the drawings is arguably reduced, but it's sure nice if you have the budget. I'd prioritize this on the drawings where 'errors' were found.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Validating 3D models from 2D drawings
I was very afraid of your first statement. *girl laughs.
I said the same thing. I don't even want to start talking about the errors in our bill of materials. That is a subject in need of a couch, a 2:00 appointment, and a few pale ales...or tequila...!
I felt like leaving 2D as 2D unless changes were required would be the right thing to do but the person that made the decision to convert the entire vault was about 4 steps over my head on another continent! So.....here I am trying to make the best of a bad situation and just get through to the next phase!
RE: Validating 3D models from 2D drawings
Also make sure the folks doing your conversion pay attention to actual dimensions and tolerances. Many are content to just hack-and-scab away making 3D directly from 2D geometry without check whether inout or output is accurate.
Expect lots of questions. If you don't get questions, expect problems.
RE: Validating 3D models from 2D drawings
You have perfectly good 2D drawings that you are using or have used in the past to make parts.
You (or your vendors) already have CAM/CNC files for these parts.
What does the conversion from 2D to 3D model and then to 2D print again gain you?
Nothing that I can see.
New parts, new system. Legacy parts, leave well enough alone.
RE: Validating 3D models from 2D drawings
<pejorative>TOP MANAGEMENT</pejorative>
already decided, of course.
No amount of derision is appropriate; there _isn't_ enough.
Mike Halloran
Pembroke Pines, FL, USA
RE: Validating 3D models from 2D drawings
Your idea of updating as needed has some merit, though it can cause its own problems as it ripples up through the pack.
One important thing is to have some rules of modeling, especially regarding the 'fudging' aspect, especially if there is a desire to use the models to help create CAM programs.
Thinking about it some more, getting real parts made from the new drawings/models might not be a bad plan.
If the initial 2D drawings are in any way 'dubious' then it will likely be a real pain.
I've got one 2D drawing from several years back that I was meant to model, redraw & release. I've never been brave enough to ECO it 'cause it's just not clear where some of the dimensions are too, and it's a kind of inseparable assy which is tricky to model. Fortunately, the enthusiasm for that task died back in 07 when I got given the checking role and the bottom fell out of the market for affected products, so no one's asked me about it lately.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Validating 3D models from 2D drawings
And that person will get a slap on the back and a bonus/promotion for "moving the company forward" instead of a kick in the backside for pouring money down the drain. I hate corporate weaseldom, but you might be well served to document dates, meetings, problems, decisions, counter-arguments, etc. in full CYA mode in case someone tries to pin fault on the person overseeing the directive (you) instead of on the person who issued it. It won't work, the management/executive fraternity watches after its own and is generally blind to their stumblings, fully content to lay blame on operations or engineering. You might get lucky and there be one VP or something who moved up from engr or ops and who will understand you're carrying out a flawed policy.
RE: Validating 3D models from 2D drawings
Luckily we do have said VP...who moved up from Engr or ops and who will understand I'm carrying out a flawed policy. But he has the added pressure from those above him to see this all the way through to the end.
Someone mentioned CAM programs which we do have for all of our parts that are also being re-done from the solid models we are creating. They want everything Engineering does to drive what all of the other departments do. The idea is genius in theory and part of my responsibility is to build workflows aside from the migration.
Whew...I wanna cry! Just saying it in my head made me panic!
RE: Validating 3D models from 2D drawings
Not an ME type, but I'd agree that your company will take years to recover from this. As this project starts to overrun, there will be great efforts taken to shortcut the process, and those drawings involved will suffer greatly. Actually drawing checking will be minimized to save costs, and all sorts of mistakes will propagate. Even the first drawings that get the mort scrutiny will have transcription errors, and new errors introduced because of the new software. A worst-case scenario is that you'll find, at the end of the process, that something fundamental was done incorrectly, and that every drawing will need to be retouched; hopefully that's just my paranoia.
As a wise person once said, "If it ain't broke, don't fix it." Seems like a lesson to relearned, and relearned, and relearned, and ...
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
RE: Validating 3D models from 2D drawings
Previously we had been talking to them about "converting" one series of our existing drawings (mostly paper scanned as TIFs) to solid models to ease designing new products of different sizes.
I don't see how that project could succeed without 100% checking of everything they do.
RE: Validating 3D models from 2D drawings
We tried vaguely similar to another company in the US and it really didn't work out well. Basically we had drawings for an existing product that were not of a high standard and limited what machine shops etc. we could use - basically we had to use the shop that worked out the bugs 10 years ago during prototype and had their own set of red-lines or similar and could charge whatever they wanted.
So we found a company that seemed to have some pedigree/reputation. Basically told them to check some drawings to correct errors and bring up to current drawing standards etc. We made a reasonable effort to state our expectations, gave them copies of our DRM, some ground rules, some functional info...
They did a pretty poor job, no apparent understanding of GD&T beyond the most basic level.
We then paid for them to incorporate the charges and they started charging us for training time for them to train a new checker or something like that.
That was the end of that experiment as far as I know.
It can be difficult enough to get new/contract employees to do things 'the right way' let alone another organization entirely, let alone another organization in another time zone.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Validating 3D models from 2D drawings
Yeah, several years ago I figured out that an "engineer" in India could be some guy who went to a 6 month Vo-Tech type program and learned how to operate the CAD system. Having the remotest clue of what it is he's trying to CAD is not a requirement. I guess they don't like the term "drafter". But even then, I've seen stuff where even if you title them "apprentice beginning drafter, Jr. grade", their work wouldn't be up to snuff.
Now they're all geeked up touting SolidWorks' feature-based 3D modeling as the greatest thing since sliced bread, but if they don't have sense enough to do it correctly, the program is not a panacea. Garbage in, garbage out.
RE: Validating 3D models from 2D drawings
I did make a point to ask my boss what the relevance was of converting old and outdated product to 3D and also to find out why we needed to recreate drawings and he stated that our old drawings are very flawed and needed revamped.
I left it alone and crept back to my desk to quietly weep!
Does anyone feel sorry for me yet? *girl smiles
I could probably start about 20 more threads to see if any of the other tasks I have been assigned have been accomplished successfully in the past.
I don't want to relearn lessons....dispite what my momma may say behind my back. *girl laughs
RE: Validating 3D models from 2D drawings
Been there.
The advantate of copying your 2D stuff into SolidWorks is that you wind up with a library of existing stuff to use in new designs. This is an advantage of 3D CAD in general.
SolidWorks comes with a DWGeditor that reads AutoCAD files. There are some Mikey Mouse CAD programs that read and write them too. Once AutoCAD is purged from your machines, you still can get at and edit your old files.
Perhaps you can get your boss to work out priorities. If you have stuff that is currently being manufactured, that must be supported, and that may be installed in new designs, you want this stuff imported into SolidWorks.
I have imported a lot of AutoCAD drawings into SolidWorks. The best method is to reproduce your old drawing, however crappy it is. This makes the new drawing easy to check, since you are just reproducing the old numbers.
If something is being done wrong, you, your drafter, or your checker should generate a formal change request. I think this is appropriate. Importing drawings into SolidWorks is one task. Fixing bad GD&T is another task. Maybe your change review committee or the original designer will not agree with you about your change.
RE: Validating 3D models from 2D drawings
Seriously though, the fact you aren't just looking to cookie cutter copy the drawings, but are looking to correct/update them makes things a whole lot trickier.
Good luck.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Validating 3D models from 2D drawings
But you are using them to make parts. Right?
So it seems to follow that somewhere there is a collective tribal knowledge of how to really make each part.
Your machinists have little back note books. Your vendors have have marked up prints. You have CAM tooling files that are "tweaked" from the drawing.
How do you collect this tribal knowledge and communicate it to your Indian brethren so that their end product will be "right"?
I'd say you're doomed.
Sorry.
RE: Validating 3D models from 2D drawings
My opinion on the matter is kind of the way we're handling this same issue. Leave them be until you want to revamp that product. Then start over with a white sheet of paper and redesign everything and basically obsolete, or recreate the existing AutoCAD parts as needed.
Blindly recreating existing drawings is not really a good way to go. You really need to consider the whole picture. Also the way the models are created might create a nightmare for making changes, etc later on. Ie, consistency and modeling practices will make or break you later on with this. That's why a fresh look is a good thing. You'll be able to better see fitup issues, problems with dimensions, etc.
James Spisich
Design Engineer, CSWP
RE: Validating 3D models from 2D drawings
Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services
www.infotechpr.net
RE: Validating 3D models from 2D drawings
""Your machinists have little back note books. Your vendors have marked up prints. You have CAM tooling files that are "tweaked" from the drawing.""
Many years ago when working for a large aircraft manufacturer, my department ran into this exact problem.
The company had a Yoder multiple roller mill on which the Z sections for fuselage frames were made. These were later stretch formed to shape. The company farmed this job out and shut down the roll forming line.
The new sub contractor sent in the Z sections that were perfect to the engineering drawings. When they were stretch formed they were 1/10" undersized.
On a hunch I grabbed my supervisor and we went to the rolling mill area, where the machine used to reside, and found the old foreman's desk. Inside was a 40 year old marked up print, increasing the dimensions by (you guessed it) 1/10". This information was forwarded to the engineering department who made the appropriate corrections. This little bit of tribal knowledge had lurked around the company for ever.
In spite of the company and FAA directives that marked up prints were not to be used.
B.E.
RE: Validating 3D models from 2D drawings
I use 3D in AutoCAD all the time. In some ways, such as designing geometrically, I like it better than SolidWorks.
RE: Validating 3D models from 2D drawings
The feedback I am getting has been great. I did want to mention that we pull drawings every single time the part is made and the programs are pulled in the same fashion and then compared to the drawing. The drawings follow the parts all of the way through to assembly.
I am not sure how other industries handle the drawings (if they are a once and done until changes are made). Granted, the most major of problems we have came across thus far is over dimensioned/under dimensioned drawings.
We are handling this on a family basis and not starting the next family until we are confident the work is done correctly. The process is very daunting and slow.
I am starting to see both side of the fence on this issue and can definitely see value in leaving well enough alone and also redoing everything to make sure it is correct (not that 100% accuracy is attainable) *girl winks.
Bright side...I've quit crying about it and have put on my big girl pants to move forward! HaHaHa
RE: Validating 3D models from 2D drawings
Both Essentially kept all engineering controls on the drawings and didn't worry about keeping controls on the 3-d models.
The first company was a smaller (30 engineers) fabricator of high precision aircraft parts. Friday all 2d drawings were live with UG. The following Monday all 2d drawings were converted to frames and every drawing change required a new 3d model that the engineering staff would make and then create the new drawing from. This gave a lot of opportunity for training and if something wasn't broken (35 year old drawings) nobody tried to fix it.
The second company. (200ish engineers in my department) has had 2 different 2d packages and are now converting from Pro-E to Catia. Same thing. Drawings are all that matter to us and models are just the means to create them. We are converting the models but don't really care that much if they create the proper drawing until it becomes time to change them. Then if its wrong you fix it or recreate the model and move on. We expect to see about 5% of the models come through bad. Haveing 5% of the drawings get changed overnight to something different with no person checking them sounds like a problem I wouldn't want to deal with.
RE: Validating 3D models from 2D drawings
We do currently have someone checking them. Which is the good part. From what I gather, there is no one good way to validate the data. Which is what I was afraid of. We are putting workflows in place that prevent a "green light" on the models until they are adequately (relatively loose term at this point) checked to the original 2D data. At that point they will be approved in the workflow inside of ePDM.
Luckily, I control the workflows so I do have a small amount of decision making abilities. *girl smiles.
Thanks for the feedback, it is always appreciated.