Creating models to mimic how products are created in "real" life

[SWUSER71]

This is how our company is currently creating models, the want to create models to mimic "real" life...
1. Create a "part file" of the purchased item(s) (raw material).
2. Then insert the parts into an "assembly file" and create a weldment "sub-assembly".
3. Insert the weldment "sub-assembly" into a top-level assembly, and make ALL the machining cuts from within this assmebly file.

This is how they do things in the shop, all parts are assembled and welded together, then they machine the part(s).

I am trying to tell them that by trying to mimic "real" life 100% within SW we are losing capabililties of A LOT of tools. You lose accessability to a lot of the feature tools in assembly files.
My suggestion is...
1. Create a "part file" of the purchased item (raw material), create configs for "Weldment" and "Machining".
2. Insert the parts into the appropriate "assembly file" by selecting the approriate config.

They want traceablility of what parts/materials are used, to be within the model files. I think that this can be accoplished by "renaming" the features to the items "part#".

Any thoughts?

 

[ShaggyPE]

At first glance, I agree with your methodology. Typically I do recommend replicating the real world process within the modeling environment. But like you mentioned to flat out conformance to this practice 100% of the time is not ideal.

Your drawings can identify the necessary details to ensure traceability, there is not a need for the models to conform 100% of the time.

-Dustin
Professional Engineer
Pretty good with SolidWorks

 

[drawoh]

SWUSER71,

I would prefer to mimic the manufacturing process.

When I design machined parts, I start the model off as a block the encompasses the whole volume of the part, then I remove material. This helps me keep the machining simple, and the part cheap.

For castings and weldments that require subsequent machining, I model the casting or weldment. I create an assembly, I attach the casting or weldment and I do the machining at the assembly level.
[ol]
[li]Again, I can see how I am doing my machining. I can avoid a lot of difficult machining operations. There is all sorts of stuff you can do at the part level that cannot be done in the real world.[/li]
[li]Someone has the option of using my casting or machined part as the base for their own weldment. The casting/welding drawing and model are not modified in this process. The earlier casting or weldment and its machining are not affected.[/li]
[li]Cutting stuff at the assembly level is not nearly as inconvenient as it used to be. I am still on SW2007 here, but I can do extrude cuts, revolve cuts and use the hole wizard. The terminations of the holes are somewhat limited, but not unmanageably.[/li]
[/ol]

JHG

 

[rgrayclamps]

Hi, SWUSER71:

SW models and their associated drawings are 3D math data. They are basically definition for parts and assemblies. They have no thing to do with how they are to be made.

ASME Y14 specifically mentions to document a part without specifying manufacturing methods.

With that in mind, my oppinion is whatever is the most efficient (to user and computer), is the way to go to define your models.

By the way, weldments are better handled though weldment part than assembies.

Best regards,

Alex

 

[Eltron]

If you are worried about loss of SW functionality forget about assemblies. You can do exactly the same thing in a multibody part environment. Just insert your stock material into the part file and remove material from there. Then you can save out the bodies as separate parts.

Dan

http://www.eltronresearch.com

Dan's Blog

 

[SteveMartin]

I'm with Eltron here. I hate to do material removal in an assembly unless it's the only way. I use inserted parts (inserted into another part file, not an assembly) when I need to have separate models for 'as cast' and 'finish machined' components. I prefer simply using configurations for this.

I recognize the idea behind starting with a block and machining down, I think I was even taught that way. I've come to see it as a waste of time. Every face you create and eventually blow completely away is a waste of time, as are most times where 2-3 (or more) features are used to make something that can be done in one.

Model what final geometry you want, make sure it IS machineable (under whatever limitations your shop must work), document it, and let the machinist or programmer build it however works best.

 

[Eltron]

The important thing to mention with multibody parts is that if you are going to use the hole wizard to create hole you shouldn't do that in the top-level multibody. The call outs won't transfer over into your drawings of the bodies if you save them out as separate parts. Hole wizards should be done outside of the multibody in this case.

Dan

http://www.eltronresearch.com

Dan's Blog

 

[rgrayclamps]

Hi, Dan:

I do not see reasons to save bodies out as separate parts. You can always detail any "body" in part drawing with hole wizard (in the top-level multibody). Hole wizards can be done in the multibody.

Best regards,

Alex

 

[Eltron]

There are several reasons to save bodies as parts. You may want a functional assembly, drawings, BOM, and PDM are a few. I don't always save them out, though. Really depends on what I'm doing with the models.

Dan

http://www.eltronresearch.com

Dan's Blog

 

[rgrayclamps]

Hi, Dan:

But a multibody part has no BOM. It only has a cut-list. A body in a multibody part is considered as a partial part, which is not supposed to be reused in any assemblies.

Have a nice weekend and Holiday!

Alex

 

[Eltron]

That's why you save the bodies as parts then insert them into assemblies.

Dan

http://www.eltronresearch.com

Dan's Blog