How do you handle vendor components?

[mike miller]

Here is a real-life example. I started out working on a conceptual model that requires a gas spring: https://www.mcmaster.com/4138T54-4138T544/
I followed our normal procedure; in this case (because it's a McMaster part) I downloaded the model, doctored it up, added our custom properties, etc. However, by Rev 5 of the design phase we decided we need a spring with a cushion. The problem is, the cushioned spring comes from a different vendor and the ball joints are not included and must be purchased separately. How should we handle this? Do I need to create a new model (or revise the current one), change the custom properties, break out the assembly into lower levels for the ball joints, and go through our jerry-rigged ERP to update it all?

How would you handle a situation like this? Is Engineering responsible for updating CAD files and file properties just because Purchasing decided to switch vendors? Should Engineering simply give them a Part Spec sheet and bury their collective heads in the sand?

[HerrTick]

Truth! Buying can be as much (or more) work than making. This is where ERP people need to get cooperative and creative.

It does sound like this needs to be an assembly.

[matt]

Engineering has to work with purchasing to specify stuff that can actually be used. Do you have separate design and manufacturing engineering depts? The people who run the CAD should do the right documentation. If you write assembly instructions, the model needs to reflect the process. A model that doesn't reflect the result of purchasing or the input to assembly is going to cause confusion. Plus, you've got to worry about the BOM. The BOM should be the BOM. If you have separate engineering and manufacturing BOMs, that's only going to take more work and cause confusion.

So yes, I think it needs to be an assembly, and you probably need a new set of part numbers because nothing about the one piece purchased part is interchangeable with the multi-vendor parts.

[MJuric]

Here is a real-life example. I started out working on a conceptual model that requires a gas spring: https://www.mcmaster.com/4138T54-4138T544/
I followed our normal procedure; in this case (because it's a McMaster part) I downloaded the model, doctored it up, added our custom properties, etc. However, by Rev 5 of the design phase we decided we need a spring with a cushion. The problem is, the cushioned spring comes from a different vendor and the ball joints are not included and must be purchased separately. How should we handle this? Do I need to create a new model (or revise the current one), change the custom properties, break out the assembly into lower levels for the ball joints, and go through our jerry-rigged ERP to update it all?

How would you handle a situation like this? Is Engineering responsible for updating CAD files and file properties just because Purchasing decided to switch vendors? Should Engineering simply give them a Part Spec sheet and bury their collective heads in the sand?

If the part has been entered into the ERP you pretty much have to pull a new part number, at least here. Even if the job hasn't been released yet once the part number has been pulled anyone in the company that does a search and finds that part can put it into their design. Change the part and now you have two different parts with the same part number.

We sometimes play fast and loose with this rule to cut down on too many parts that we will never use. So for instance if someone puts a part in the ERP system that we pretty much know that no one else will use and we know purchasing hasn't ordered it yet, we'll re-use numbers and just change the ordering information in the ERP.

However most of the time it's new part number every time.

[berg_lauritz]

The biggest question for us is always if this is a 'structural change'. Even if the same part changes in a structural way (different bolt hole locations, outer dimensions change in a crucial way, etc.) we make a new part #. This is for our reference regarding warranty purposes.

If it is 100% interchangeable & we just have i.e. a different vendor to it - Design does not change anything. Purchasing sets i.e. a 'preferred vendor' & a link to a part (which can also be an internally manufactured part) with which it is interchangeable with. They also mark which version is used for this specific unit to prevent issues for warranty purposes.

(Regarding SolidWorks) To prevent mate errors etc. we decided recently to ONLY use reference geometry to mate purchased parts (even if it is a plane, that is coincident to a face). This way you can set up the new part exactly the same and do a 'replace with' with as little errors as possible.

Does that help?

Edit:
i.E. (for SolidWorks) I understand, that you had a part before & you probably want to replace it with a part to prevent useless mate errors. Just go for a multi-body part & make a cut-list for the new part. Then explode the BOM for this part to show, that it needs two different pieces from different vendors.

[Tom G]

(Regarding SolidWorks) To prevent mate errors etc. we decided recently to ONLY use reference geometry to mate purchased parts (even if it is a plane, that is coincident to a face). This way you can set up the new part exactly the same and do a 'replace with' with as little errors as possible.

I love this. Once you get used to it, it's indispensable. Exactly same naming across components also helps it identify its replacement entity immediately. Further, all reference geometry is (are?) available in a lightweight mode large assembly, to select from the tree for new mating.
(Care should be applied to polarity orientation of planes and axes, which is shown by the location of its name when visible. A misoriented axis will produce automatic errors, even if easily identified and reversed later.)

[Lapuo]

If the part is same i dont care which vendor purchasing team will choose
Well , if parts are different , but for same intention yes we need another part number and because of that reason models are also replaced at assembly
for example same size fastener but different material - here we need to make another model with its own custom properties and replace them at assy

[mike miller]

Engineering has to work with purchasing to specify stuff that can actually be used. Do you have separate design and manufacturing engineering depts?

No. Thank God. If we did we would need a full time HR ninja for sure.

The people who run the CAD should do the right documentation. If you write assembly instructions, the model needs to reflect the process. A model that doesn't reflect the result of purchasing or the input to assembly is going to cause confusion. Plus, you've got to worry about the BOM. The BOM should be the BOM. If you have separate engineering and manufacturing BOMs, that's only going to take more work and cause confusion.

That's what I don't understand about @jcapriotti's philosophy of EBOMs and MBOMs. Doesn't that just deliberately muddy the waters?

So yes, I think it needs to be an assembly, and you probably need a new set of part numbers because nothing about the one piece purchased part is interchangeable with the multi-vendor parts.

That's kind of the direction I'm leaning as well. I think if all our data was on the cloud this problem would go away.

[jcapriotti]

That's what I don't understand about @jcapriotti's philosophy of EBOMs and MBOMs. Doesn't that just deliberately muddy the waters?

Not my philosophy, just the direction our company is going and enabled by our switch to Windchill. We currently have an engineering center and manufacturing center in 7 different countries all making variations of the same product. Each country has different building codes so it's slightly different but many components could be the same. Our global parent wants one system but they also want to separate the engineering from the manufacturing. The idea being that a component could be designed in any of the 7 engineering locations but made in any of the factories (probably doesn't bode well for our US factory).

Currently in our legacy systems, the engineering bom is the manufacturing bom, minus shipping materials which they do append in their system downstream. What our global parent doesn't like is it ties the design to that one factory. This Windchill ebom to mbom change has major structure differences that are difficult to follow because our engineering group now no longer considers mfg process, just manufacturability. Windchill has tools to manage it but clearly they are lacking a UI designer as it's a confusing mess of a tool to use.

The messy part for us is with an assembly BOM, where the EBOM and MBOM differ so much, how do we make the drawing/model work? Its created for the EBOM but doesn't match the MBOM. Do we copy and modify it to match the MBOM? Now we would have to duplicate model assemblies for just about everything, and it has to be updated twice. I'm just not sure about it, and have been curious how other company do this, but besides lots of PLM software demos touting this as a godsend, I can't find many examples.

[DanPihlaja]

Here is a real-life example. I started out working on a conceptual model that requires a gas spring: https://www.mcmaster.com/4138T54-4138T544/
I followed our normal procedure; in this case (because it's a McMaster part) I downloaded the model, doctored it up, added our custom properties, etc. However, by Rev 5 of the design phase we decided we need a spring with a cushion. The problem is, the cushioned spring comes from a different vendor and the ball joints are not included and must be purchased separately. How should we handle this? Do I need to create a new model (or revise the current one), change the custom properties, break out the assembly into lower levels for the ball joints, and go through our jerry-rigged ERP to update it all?

How would you handle a situation like this? Is Engineering responsible for updating CAD files and file properties just because Purchasing decided to switch vendors? Should Engineering simply give them a Part Spec sheet and bury their collective heads in the sand?

I would say yes. You need to go through your ERP system.

Real world example as to why:

We ordered natural plastic clips to clip two rods together for a hood latch project that we were doing.

After testing passed and we were working on getting production under way, the vendor had a temporary supply problem and couldn't keep up with our need for the natural plastic clips. They did, however have black clips that were the same in every way, except they were black in color.

There was an argument for just swapping out the clips because it was a temporary change and not going through the change process. Even when we contacted our customer, they were in favor of just swapping out the clips and doing nothing else. One of our engineers, however put his foot down and said that we had to go through our change process for swapping out the clips. Even though the process would take a long time for something so insignificant.

And we are glad that we did. Because, for the clips that had the black dye added to the injected molded material, the dye actually made the material slightly more brittle. And once these clips got into vehicles, they started failing (cracking). There was a recall. It wasn't a safety issue, but it still sucked.
If we hadn't gone through our change process (and our customer's change process) (even though we were pressured NOT to go through it by our customer AND our upper management because of the insignificance of the change), then it would have been VERY hard to track which hood latches had the black clips and which ones didn't.

Moral of the story: Things that aren't the same........are different. No matter how much alike they are....