Manufacturing guy-at-large.

Filtering by Tag: STEP

McMaster-Carr and the Future of Parts

Added on by Spencer Wright.

Last year, I wrote a post describing my feature requirements for a modern parts management system. Re-reading it today, I realize that it doesn't really say what the user interaction would feel like - or how it would work at all. I hope to provide some of that here.

The key is this: Integrate small parts inventory management into the product design, prototyping, and maintenance, repair & operations processes. I'll treat these as three separate use cases, though they're all part of the same product lifecycle.

The reader will note that I believe McMaster-Carr to be the strongest positioned organization to take on these tasks. As a longtime fan of McMaster and a student of their intense customer focus, beautiful interface design, and impressive supply chain management, I hope that they seriously consider these recommendations - as I'm sure that their competitors will be soon.

Note: I diagrammed an early version of this idea in a flowchart here.

My current "system," during prototyping on  The Public Radio.

My current "system," during prototyping on The Public Radio.

During Design

As a hardware product designer, I want my suppliers' parts catalogs integrated into my design environment, so that I can seamlessly browse for new parts and view part data directly from my modeling software.

Autodesk Inventor is my go-to design software, and McMaster-Carr is my go-to parts supplier. I'm constantly browsing McM for a part, then adding it to an open order, then downloading the STEP file and importing that into my model. I consider this a luxury: McM's decision to include STEPs for the vast majority of their mechanical parts makes my job a ton easier. But the process is convoluted, and a lot of part data is lost. On parts like socket cap screws, for instance, McM tracks the following data:

  • Thread size
  • Length
  • Thread length
  • Material
  • Package quantity
  • Package price

But their STEP files contain none of that; all that's included is the part number and the material, which is often stripped of a lot of useful data (parts described as "Type 316 Stainless Steel" on McMaster's site often show up as either "Stainless" - or worse, "Generic" - in the STEP file).

For McMaster-Carr to become more fully integrated into my design and procurement process, they should include comprehensive part data in all of their STEP files. 

Moreover, there's a larger opportunity for McMaster to integrate their catalog directly into my design environment. If their catalog were available as a plugin for Inventor/Solidworks, designers could browse, design, and purchase all from one seamless interface - which I believe they will demand in the near future. Look at Plethora and Sunstone Circuits (and in web development, Squarespace) - across the hardware world, the movement is towards integrating design & supply chain management. McMaster-Carr is perfectly positioned to become a powerful player in the field. 

During Prototyping

As a prototyping mechanic, I want real-time internet enabled inventory management, so that I can understand what parts I have on hand & prepare for shortages before they happen.

Small parts management sucks. With their lightning-quick delivery and vast catalog, McMaster is the cornerstone of most prototyping shops' parts management system. But that solution is awkward at best, and often requires simply ordering more parts, even if we have some (somewhere) on hand. 

Small scale inventory management has historically been extremely difficult, but today it's increasingly easy. For instance, Quirky has shown us that it's not that hard to keep track of the number of eggs you have in your fridge, and Tesla's iOS app shows the charge state of your car's battery. It's only a matter of time before the same is the case with things throughout our physical lives, and McMaster-Carr is uniquely positioned to take small parts management on.

I envision a small parts cabinet full of sensors (some combination of force, optical, or proximity), which would periodically update an online database as to the quantity of parts inside each bin. But you needn't even start there. An easy MVP would be an iOS app that allowed the user to snap a photo of a small parts cabinet and tag each bin with a part number & quantity. The photos would be collected and stored online, and would be linked to the customer's McM order history. 

Then, when a mechanic takes a handful of bolts out of a drawer, all he needs to do is update the inventory count from his app. By tapping around a set of linked photos in the app, he's directed to the bin that he's physically looking at - and he can confirm visually that the parts are what they appear to be. By tapping on an "info" tab, he brings up the inventory data (including links to a 3D part file, technical data, order dates, and a list of mating parts/assemblies that the part has been used in - culled from the Inventor plugin described above) and assign a piece count to a job & edit quantity on hand in moments.

McMaster-Carr should build this system - starting with an iOS app that offers basic inventory management. Doing so would give them a view into their customers' usage data, and would help users streamline their restocking process. The days of bins labeled with bits of paper are numbered, and users will soon demand personalized (and internet-enabled) inventory management systems. McMaster is in a unique position in the marketplace, and has the opportunity - if they work now - to strengthen their foothold in small parts management.


As a maintenance, repair & operations engineer, I want a single process that incorporates machine data, relevant spare parts, and procurement, so that I can get my facility back online more quickly.

A large part of McMaster-Carr's business is in supporting maintenance, repair & operations (MRO) professionals. These customers have unique needs; their ability to get the right part, right now, can have huge impacts on their company's ability to recover from unplanned downtime due to a broken machine.

In many cases, MRO engineers will find themselves with a broken part and will need to replace it immediately. Doing so will require careful measurement to determine the part's specifications, a process that can be difficult and imprecise - especially if the broken part has been mangled and/or lost.

McMaster should work to establish a system of folksonomy - user contributed data - that would allow MRO customers to tag parts with information about how and where they can be used. For instance, a particular serpentine belt might be commonly used as a replacement spindle drive belt on an old lathe. Instead of finding this data on the web - and then cross referencing part numbers back to the McMaster-Carr catalog - a tag could be submitted to the relevant part directly in the McM database. Subsequent users could then find the information they need right in the McM website/app.

Such a system would be complicated, for sure. It would require a significant effort on McM's part to hire and train community managers, who would monitor and vet user submitted data on a daily basis. But doing so would allow McMaster to leverage the huge - and growing - network of hardware professionals and enthusiasts. This community is sorely lacking a single go-to reference, and McMaster is in many ways the strongest candidate (with its enormous existing database of part, material & process data) to do so.

In order to pull off these tasks, I believe McMaster-Carr will need to become more transparent about their processes and inventory data. This will be a difficult process - I myself struggle with transparency - but I believe the payoff will be well worth it. A new generation of hardware professionals & hackers have come of age in a new information paradigm, and they are increasingly responsible for purchasing decisions in small and large companies alike. These people have grown up reading Amazon's shareholder letters and following the official Google tech blog. They expect to be part of a company's product development process, and will contribute their own time, energy, and expertise to projects that historically would have been developed in private. McMaster-Carr - with its huge network of enthusiastic users - should leverage that collective energy, and work with its customers to bring parts management into the 21st century.

File conversion woes

Added on by Spencer Wright.

This is why dimensioned PDF drawings are so extensively used in procurement. The top photo is from a supplier from; the bottom one is the STEP that I originally uploaded to MFG.

Screen Shot 2014-01-04 at 9.27.05 AM.png

This supplier has obviously downloaded my STEP and performed some translation or conversion on it, and in the process has deleted a few faces (you can see the difference in the foreground of the part, and in the areas he's highlighted in red). This is clearly an inexperienced supplier, and one that I would ultimately have a *really* hard time choosing. I'm not sure what he did or how he did it, but the fact that he made this mistake is an indicator that we'd have issues down the road.

(To his credit: the photo came from a message he wrote me saying that he "noticed some missing surfaces on the part file," and asking me to fix them. So he knew that there was a problem, but didn't understand what it was and wasn't able to troubleshoot it himself.)

In traditional manufacturing, 3D part files are created and edited in a program like Inventor or SolidWorks. The parts are then brought into a separate environment in the same application and drawn and annotated in multiple 2D views on a "paperspace." The resulting drawing file (.IDW for Inventor) is a dynamic representation of the original part; if you modify the part file, the drawing will update automatically. 

You *never* submit drawing files directly to a manufacturer. Instead, you export PDFs of the dimensioned drawings, and *optionally* include STEP files (which are essentially cross-platform 3D files) as a courtesy. The STEPs can be used to help the manufacturer set up their CNC machines, but they're for reference only; the PDFs (with all their dimensions and annotations) are what you're buying.

"Organic" shapes - like those that 3D printing is so well equipped to make - don't fit into this process well. Complex surfaces are *really* difficult to define clearly and completely in two dimensions, and so most 3D printed parts are built from solid files. In this case I submitted a STEP, which manufacturers will convert to an STL and then run through a slicer and feed into their machines.

The problem is that STEP files aren't immutable, and the supplier in this case has apparently deleted a feature from the part. In this case the result was obvious, but there are a lot of features that he could modify or delete that would be a lot more difficult for him to detect, and my QC job would be accordingly tricky.

This process should be better. The PDF workflow is inconvenient, but at least it's an effective barrier to issues like this one. 

Also, we need more, and more *good*, DMLS suppliers. 

STEP files

Added on by Spencer Wright.

From Step Tools, Inc.'s excellent overview of STEP purpose, applications and development (emphasis mine):

The ultimate goal is for STEP to cover the entire life cycle, from conceptual design to final disposal, for all kinds of products. However, it will be a number of years before this goal is reached. The most tangible advantage of STEP to users today is the ability to exchange design data as solid models and assemblies of solid models. Other data exchange standards, such as the newer versions of IGES, also support the exchange of solid models, but less well.

But later, in the "Future of STEP" section: 

The real issue that stops faster STEP deployment is the commitment of those with the resources necessary to define the standards. The government does not like to pick solutions for industry, and industry does not like to fund the development of solutions that can also be used by their competitors. Consequently, much work only gets funded in situations of clear and desperate need such as when the high cost of manufacturing is causing excessive job losses.
The Internet and the World Wide Web broke through this cycle when "killer" applications made the benefits of the new infrastructure clear and compelling for all users. AP-203 made STEP useful by allowing solid models to be exchanged between design systems. AP-238 will make STEP compelling for some users by allowing them to machine parts more efficiently. However, like the early Internet there will be alternatives that are considered more reliable by other users. The killer application that makes STEP ubiquitous has yet to be identified 

There's a lot of good info on STEP buried in obscure corners of the web. I hope to be summarizing some of my research on the topic soon.