MBD experiences

Anyone using SolidWorks MBD?

Chris, CSWP
SolidWorks
ctophers home

I looked at it, but I don't see a reason to use it at this time for my use. Sorry brother!



Scott Baugh, CSWP
Mechanical Engineer
Ciholas

"If it's not broke, Don't fix it!"

Click to expand...

faq731-376

Thanks Scott.
I don't see a reason either. But, being mandated here.
Not much support anywhere because not too many companies using it.

Chris, CSWP
SolidWorks
ctophers home

ctopher,

Am I the reason you deleted your last question about this?

My experience with MBD was that our partner, a large aerospace company, was doing it. They were designing large, complex machined parts, and apparently sending the 3D[ ]data to their in-house machine shop. My boss was impressed, so she decided we had to do it too. All of our fabrication was sub-contracted. We decided that we had to restrict ourselves to machine shops that had CMMs. Note how our partner was not managing vendors.

What problem are you solving by implementing MBD? Is your geometry so weird and complex that you cannot draw it in[ ]2D? Is the money you save by not preparing drawings not being fully offset by the extra costs incurred by manufacturing and inspection?

--
JHG

drawoh,
No. Someone here at work commented to me personally, so I removed it.

Our CEO saw MBD and thought it was cool. I have no problem with that. But, has been a struggle implementing it.
We are trying to add MBD to the models, import the data into inspection software and use in Mastercam.
The Mastercam part is easy.
We are trying to streamline the process, without making paper drawings.

I have found bugs in the SW MBD addin. A ticket has been submitted.
SW told me that there isn't a push to update MBD because there are not many users.

Chris, CSWP
SolidWorks
ctophers home

ctopher,

I archived thread1103-322065 because it was interesting. Note how QA guy Dingy2 got way more stars than I did. You need to communicate with your vendors what is critical. Is there a 3D[ ]language that everybody understands, that provides GD&T?

At a job subsequent to the one I noted above, I was working for a company whose people I had a lot of respect for. Their system was to not dimension everything. There was a note on drawings that stated that undimensioned features were to be fabricated to their standard production tolerances. My employer was obsessed with GD&T and DFMA, and they knew what those capabilities were. The dimensions and tolerances actually applied to the drawings were critical. This is convenient for whoever has to do the First Article Inspection (FAI) report.

I strongly prefer to do my own drawings, and I prefer complete dimensioning. Rarely does this take me a long time. I don't see how MBD saves money. If my drawing takes a long time, it is because it is complicated, and I have to think about what I am trying to do. Some nasty problems on the fabrication drawings are solved by me changing the design. Drafting is your final opportunity to pass your eyeballs over your part.

--
JHG

drawoh,
I 100% agree.
I have been making drawings for 45 years and can make a detailed drawing quickly.
But, our CEO is mandating we go the MBD route.
There are alot of machine shops don't care about MBD and want dwgs.

Chris, CSWP
SolidWorks
ctophers home

ctopher,

I assume you are pulling up your 3D[ ]model and applying tolerances to the critical features. This requires you to think about what you are doing, which is how you spend most of your time drawing up anything complicated. It also requires your vendor to run whatever software is required to read off your 3D[ ]model annotations.

At my MBD site, my boss admitted that one of the machine shops made a point of preparing their own fabrication drawings. If the shop has to prepare 2D[ ]drawings, these are part of the NRE that will be quoted on and that you will pay for. Shop-prepared drawings take us back to the Critical Dimensions discussion linked above. How does the shop work out critical dimensions? What if the shop sends you their drawings and tells you "Here is what we are going to fabricate to. Please review and approve them."

The nice thing about PDF and STEP files is that everybody can read them. You can pick the vendor who does the best work, delivers the best value, and/or is located next door to your office. You want to deal with fabricators who are good at fabricating and who deliver quality work on time. The software they run should be a secondary issue at most.

Right now, Billy Bob and Cousin Elmo's Machine Shop needs to install and maintain enough copies of SolidWorks, CREO, Inventor, Solid Edge, OnShape, and whatever else, to get work done. Their people need to be trained on each of them. If they are doing to work directly off the 3D[ ]model, they need multiple copies of them. They can reduce their need for CAD licenses by having one guy making 2D[ ]drawings of everything, and working off of those. This might be a good business for a consultant. I use SolidWorks to generate fabrication drawings out of SolidWorks models the fabricators send me. I support several fabricators, thus leveraging my SolidWorks license. My comments above about critical dimensions continue to apply. If you have security issues, does your vendor know how to vet vendors like me? If you run IronCAD, your machine shops will have fun finding consultants.

I am trying to learn FreeCAD. This is Free[ ]Software, which means that everybody can install and use it and keep their versions up to date. This may be the solution to MBD software.

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JHG

Critical dim's are added to the MBD. There is no need for vendors to have SW installed, most can import STEP242, or thru free eDrawings.
There are some small machine shops that refuse and want full drawings.
One problem I'm having with 3D MBD PDFs is not all companies have the same version, so the data comes thru weird.
It's a slow process to make it work efficiently, and to management's liking.

Chris, CSWP
SolidWorks
ctophers home

ctopher,

Which version of SolidWorks are you on? I am on 2021 here, and I cannot write STEP242. STEP214 does not capture annotations. Can you scale off of 3D PDF files?

Regardless, something, somehwere must tell the vendor what your default tolerances are. Either you have a 2D document of some sort, or you methodically write an instruction to your PO.

--
JHG

SW 2022. You have to have the MBD addin to write to STEP242, and create the MBD PDF dwg. All of the dimensional/tol data goes with it.

Chris, CSWP
SolidWorks
ctophers home

Hi, Chris:

I use SW2022. But I don't see the MBD addin. Does it come with standard installation of SW 2022?

Best regards,

Alex

Alex, it's a purchased addin.

Chris, CSWP
SolidWorks
ctophers home

What I really like about CAD companies is when interoperability is an extra cost item.

That's sarcasm is what that is.

I agree!

Chris, CSWP
SolidWorks
ctophers home