Back in my first blog, I reminisced about my days as a draftsman. For this topic I am going to do the same. Back then we used lead pencils on paper or vellum. When we needed to share drawings with the shop, we made blueprints of them using a very large ammonia based blue print machine that looked like it would as soon eat you as make a copy of your drawings.

I remember being mentored by the senior engineers. One of the things they use to tell me was I needed to always consider how something I was designing would to be made. To make sure I did this, they would have me spend time in the shop. While I would help where appropriate, my main goal was to observe how things were being manufactured. I would watch everything from machining to assembly. This was invaluable experience, as from that point on I would do my best to always ask myself on new designs or design change, “Can this really be made?” And for the most part, I could answer that question. If I couldn’t I would be sure to get with the appropriate people in manufacturing to find out before calling my design complete.

In my current position I now get the opportunity to see various engineering departments. In many places I see a big disconnect between engineering and manufacturing. There seems to be this big virtual “Wall” between the two departments. The engineering group develops a new design. They usually run through a very formal design process. And with new CAD tools like PTC offers in Creo 2.0, they can run through various analyses, simulations and interference checking all from their desk. This new capability as proven to help reduce the number of pilot runs and rework required due to design flaws. Unfortunately, with all this new automated checking, I think sometimes the engineer loses sight of how their design will actually be manufactured. In many cases I have noted that the designer really has no idea how manufacturing actually gets their designs built.

Too often a design goes through a rigorous design process, only to be “thrown over the wall” to manufacturing. Once there, the manufacturing engineer often would require changes. Best case, if they had a good PLM system like Windchill, they would start a formal change process, asking engineering to make the required changes and send the design back to manufacturing. This still costs time and money, but all CAD models will stay in sync with how the product actually gets built. However, in many companies, I see manufacturing modifying the CAD models or assembly to reflect their needs. Usually they then save their version of the objects on a local drive or network drive. These files are then completely uncontrolled files outside the companies PLM system. However, without them the product could not be manufactured. Just as important these manufacturing files do not match the designed version of the CAD files. I am not talking the “as designed” to “as manufactured” bill of materials. These often are different, and they should be. I am talking the CAD models themselves being different. This potentially is throwing all the analysis and testing done in design out the window.

I am sure for most of you I do not have to explain the risk of having uncontrolled manufacturing version of CAD files. Why don’t more engineering departments and individual designers today take manufacturing more into consideration when designing? I have a couple of opinions on this. One possibility could be the shorter and shorter design timelines engineering has to work with. They just don’t have the time anymore to research their companies manufacturing practices. Once again I challenge management to truly consider the time they supposedly save in engineering, to the risk with how things truly get manufactured. Another very good possibility is more times than not manufacturing does not happen anywhere close to the Engineering group, many times in completely different countries. What I used to be able to do when I started out, is no longer an option for many engineering departments.

I can’t say I have a complete answer to this growing problem in our industry today. However, one thing I have seen work well is a true design review meeting that includes representatives from manufacturing. Before releasing any design, it must go through one of these reviews. Any concerns with how the design will be manufactured can be brought up during this meeting, and addressed prior to design release. Another option I have seen is creating an “As Manufactured” or “As built” version of the CAD files in a PLM system. Sometime the manufacturing engineer makes the changes, sometimes they are sent back to the design group to be made.

Let’s tear down that wall! If you’re in engineering, consult the manufacturing group about your designs. If you’re in manufacturing, let engineering know you need to modify files just to get them built correctly. Talk though it, bring attention to it. If you don’t, no one else will. You may not think it affects you leaving things function as they are. But, if you are not helping you company become the best it can be, in the end it will be the employees that inevitably suffer.

How does your company deal with changes required to a design so it can be manufactured? Does your engineering group consider manufacturing during the creation of their designs? How do you train new engineers/designer’s manufacturing methods? Specifically, if your manufacturing facilities are offsite. Does anyone else feel this is a growing problem in engineering/manufacturing companies today? While I get to see many companies, I obviously do not have visibility into every company in the country. So, please, respond with your thoughts, opinions, and how things are done where you work.

I’d like to start off by clarifying the difference between eBoM vs eBoM. Most companies developing products have both an eBoM and mBoM.

• Engineering Bill of Materials (eBoM) — as designed
• Manufacturing Bill of Materials (mBoM) — as shipped

You may not agree, many don’t see it this clearly. The industry does, and therefore, some software tools have more ability than you may know. But, I guarantee, if you overlay these two elements onto what you are doing for Bill of Materials (BoMs), whether in Engineering, or in Manufacturing, or in Production, you’ll see the clarity of these two simple elements rise to the surface.

Definition of eBoM and mBoM:

eBoMs are created in engineering, are typically driven from the CAD tool, and are usually centric to the final assemblies list of parts or components that make up the as designed or eBoM.

mBoMs will contain, or be ‘driven’ by the eBoM. MBoMs make up the ‘end item’, or product as shipped. Of course, the eBoM, or ‘parts list’…the eBoM requires additional things like shipping containers, crates, peanuts, or packing foam, plastic bags for accessories, power cords, or items necessary to complete the product that is not defined on the eBoM.

Manual processes for eBoMs & mBoMs

In the drawing board days, we often communicated this detail as a table on the final assembly drawing. Sometimes as many sheets attached or referred to on the final assembly drawing. Hopefully, you’ve evolved beyond that! If not, that’s okay, there is hope. Unfortunately, many still use this legacy approach and are still creating (painfully) this table on their CAD assembly drawings. Others may be manually forming them in spreadsheet software.

The next step, and pain point, you must re-enter or get the data into your ERP/MRP tool. Either manually, or via an importation, it is error-prone. What if changes occur? But, that never happens, right?? Ha.

How much time does your organization spend on these tasks? How about errors because of changes? Do you have the role of Configuration Manager defined?

The task of creating the mBoM from the eBoM usually has many manual and painful disjointed steps. Often involving exporting out of one tool, into another, but only if you are evolved enough — as I stated earlier, many are not this evolved, but have the vision to do so…maybe you’ve already made a connection from your data management tool to your ERP/MRP system?

PLM Systems like PTC Windchill help you manage your BoMs

EAC can help you form this vision, and guide you to a better way of understanding this topic in the context of your organization. We strongly believe there is a better way to develop products – and managing eBoMs and mBoMs is just one part of doing it better.

PTC Windchill can drive the eBoM into the mBoM or vice versa. It has the out of the box ability to be the tool for the Configuration Manager roles in your organization. Options and variants are another use case you’ll see in a future blog topic.

Organizations have found ways to leverage PLM systems that transform their product development process and defeat pain points like the disjointed processes that come with manual creation of the mBoM from the eBoM.

Take a look at the Aberdeen PLM Research revealing that organizations with connected PLM see a 22% increase in engineering productivity and 21% improvement.

If you’re looking for a PLM solution such as PTC Windchill, our Product Development System Services (PDSS) team can help implement the software within your organization.

Download our free eBook on Designing an Effective Change Control Process to help understand the digital transformation movement better.