Interchangeable Parts: History and Importance

In this episode, Bill and Andrew discuss variation, the impossibility of true interchangeability and why we need to apply "shades of gray" thinking at work. Bill shares the key question that will take your organization beyond "meets specifications" and help improve your processes, so you can delight your customers.

TRANSCRIPT

0:00:02.8 Andrew Stotz: My name is Andrew Stotz. I'll be your host as we continue our journey into the teachings of Dr. W Edwards Deming. Today, I'm continuing my discussion with Bill Bellows, who has spent 30 years helping people apply Dr. Deming's ideas to become aware of how their thinking is holding them back from their biggest opportunities. The topic for today is 20th century quality, Bill take it away.

0:00:28.2 Bill Bellows: Thank you, Andrew. So the running joke on the 20th century quality is we could have said 19th century, and sadly it's still 21st century. And what do I mean by that? In our second episode, we've talked about the two questions of quality management. Question one, does this characteristic, does this product, does this thing meet requirements? There's only two answers. That's 19th century quality, that's 20th century quality, and by and large, that's 21st century quality. And my hope is that our conversation inspires people to move into question two, which opened opportunities for as you're talking about opportunities for investment, opportunities for doing amazing things, when we get out of the black and white of question one into the shades of gray, of question two. That's, that's so...

0:01:26.5 AS: So what century are we in now?

0:01:29.1 BB: I think the 21st.

0:01:30.5 AS: 21st. My goodness. People always get, I always get confused. We're in the two thousands, but that's a 21st century. And 19th century is the 1800s.

0:01:46.7 BB: Well...

0:01:47.5 AS: 20th century would then be from 1900s until 2000 or 1999.

0:01:54.3 BB: The... And just for some more clarity, and I was doing some research earlier today, but there's a great tie between question one and 19th century 20th centuries still: question number one, does this meet requirements? A lot of that ties back to this whole concept of interchangeable parts. Which is not what we do in the garage when we're in the garage building something - that's 21st century quality, because we design it, we buy the stuff again, whether you're building something in the kitchen, in the backyard, and we put it all together with a 21st century, a Deming-Taguchi approach to quality, which means we're not looking at the parts in isolation we're looking at how they come together, the idea of interchangeable parts, and the... A name that I usually find as being the father of this concept of interchangeable parts. People talk about Eli Whitney.

0:03:02.3 BB: But Eli Whitney heard about interchangeable parts from the first American to hear about this concept, who was Thomas Jefferson. And he heard about it when he was US Ambassador to France, in 1802 timeframe, he was Jeff, he was George Washington's ambassador to France. And while there he came across a Frenchman by the name of Andre Blanc, B-L-A-N-C. And Blanc is considered the... Not the father of interchangeable parts. There's a French general in the 1770s had this idea of you're in the battlefield, you've got all these broken weapon systems and I can't cobble together this cannon with these wheels to be able to continue fighting the battle because they're all crafts built with craftsmanship, which means these things don't come together. So this general had the idea, and I like to tell people, Blanc is the one who got the marching orders to go put this concept into practice. And so he's given credit for being the one to work through the details.

0:04:17.1 BB: And what I was reading earlier tonight I've done other reading on this before, but it was, Jefferson went to a presentation by Blanc, heard about the ideas. Jefferson wrote a letter to John Jay and I don't know exactly, I, John Jay's name, I... Name I've heard before. I don't know exactly what his role was in government. But he wrote a letter back that there's this thing, this guy Blanc, this concept of interchangeable parts. And as the story goes, Jefferson offered Blanc the opportunity to come to the States 'cause Jefferson saw this, not just on the battlefield, the ability to repair weapons quickly, quickly, quickly, but what this means to a growing society. And Blanc had no interest. And so Jefferson took the idea, gave it to Whitney. Whitney gets credit for the first contract with Congress ever for a product with interchangeable parts, which turned out to be rifles. And it took on the order of 20 years for him to figure out how to do that. But in the process, he was working on the design protocol, the quality system, which is 18th century quality, which is looking at all these parts, giving them requirements. And that's what we do today.

0:05:39.8 AS: So the US Congress kind of funded that research and development basically.

0:05:44.3 BB: Well, there's a fun story and [chuckle] is it a true story? It has the making of a true story 'cause he figured Jefferson is the, you know, the godfather of this movement. And the story is in the early 1800s John Adams is president and Jefferson goes to the Oval Office with Whitney to give John Adams an update on this thing called interchangeable parts. And so he brings in Whitney, you know, this is, you know, Mr. President, okay, this is Eli Whitney. And evidently Whitney comes in with two rifles and Jefferson says, okay, make me proud. And he takes the rifles apart and he moves the parts from one to the other and shows them this is what we're working on. And evidently Adams is blown away by the whole thing. Well, the punchline is that Jefferson working with Whitney's, hoodwinked Adams because the parts were handcrafted to be identical. What took another 18 or so years was his effort to create the tooling to mass-produce these, not hand-file them. It took some time. It took some time. But Whitney gets all that credit, but it goes back to Blanc. And also, in the very same timeframe, I've read of incredible efforts by the British in using this for pulleys and warships. And so this was going on elsewhere.

0:07:24.6 BB: What I've also heard... And I'll just throw out, I don't wanna go there. But I've heard accounts that the Chinese centuries before were looking at this. If somebody's thinking, "Well, was it them or... " I don't know. And so in the Google searches I was doing about an hour ago, I didn't find anything on China. But the important thing for our conversation is the idea of taking a product, breaking it into parts, giving the parts requirements, and having this sense of, "All these springs meet requirements. They're all good," which is question one. "All the bars are good, and we can interchange them." What I also say is that the concept behind question number one, saying that all these things that make requirements are good, all the barrels are good, all the locks are good, I would define that as absolute interchangeability, meaning the sense that any one of these can be put together with anyone else, and I could take any doctor, any of this, and I can absolutely plug and play. And what that ignores is variation. From a Deming perspective, which is question two, when you realize that all these parts that meet requirements have variation, that means they're relatively interchangeable, but they're not absolutely interchangeable.

0:09:01.2 AS: Which makes me think about the before interchangeability, which we're so familiar with in this modern world. Before...

0:09:08.4 BB: Everything is.

0:09:09.3 AS: Interchangeability, there was craftsmanship, whereas the difference is in those parts of a shoe, even though they may... My uncle and myself got the same shoe, there are some unique differences to those exact same shoes that the craftsman's not trying to get rid of. They're part of what... It's not a pressure that the craftsman feels.

0:09:33.7 BB: Well, handcrafted is expensive. These are handcrafted, a handcrafted guitar, a handcrafted... There's a place down the street where they... Essentially, it's handcrafted car wash, by hand. In the early days, handcrafted was the only thing. Then we went to interchangeable. And so we could have handcrafted truck, handcrafted this. But the point I wanted to make for our audience is question one does it meet requirements. There is a sense of absolute interchangeability, that I could replace this doctor with this doctor because they're both board-certified, this engineer with this engineer. It's like in the world of computers and software, it's this idea of plug and play. "I can take this one out, plug this one and just move on." And we have that sense of everyone in the organization is relatively interchangeable. The idea of interchangeability from a Deming perspective is workers are treated as interchangeable, products are treated as interchangeable, and what's missing is a sense of differences, that the people are actually different. They're not... And that's what we... The running joke we used to have with friends is that we've got... People are making parts that are interchangeable, and we're treating the people as if they are interchangeable.

0:11:03.5 BB: And that mindset of interchangeability is alive and well. Now, another thing just throw out, just for those that might not be familiar with this conversation, is that when requirements are set and I just like to say to people is, "Can a company go to a supplier and say, 'We want this part to be exactly 1-inch thick'?" And they'll say, "Yeah, we can pull that out." And I say, "Well, technically, no." 'Cause what exactly does 1 inch mean? Does it mean 1.000 inches? Does it mean we're gonna have that thickness all the way around the table? And what that is ignoring is variation. Even if I measure it and it's exactly 1.000 all the way around, well, when I ship it to your company, Andrew, and you measure it, are you gonna get the same value? And if you get a different value, does that mean I can't sell it to you? What we do is we take the 1.00 and we say, "Plus or minus some small number." We can say, "10 plus or minus 1/16 of an inch." And then we get into the world of requirements where there's a maximum and a minimum. And now what we're saying is good, which is question number one, is everything in between. And my explanation is, if we didn't allow for that wiggle room, we couldn't have commerce because we're not acknowledging variation.

0:12:49.3 BB: And that goes back to... Again, it goes back to Whitney and Blanc is a sense of, "We're gonna put bounds on it, anywhere in between." In the world of American football, that saying... Or international soccer, "Anywhere within the net is a goal. Anywhere within." What's missing from that is if, is what happens if we're at different values within that range, what, where does that, what do the differences in meeting requirements mean? And what I point out is the differences in how we meet requirements shows up when you take the thing from me and try to do something with it.

0:13:37.9 AS: So it's related to the application that it's being used in.

0:13:43.6 BB: And I don't... A question that I like to ask that I don't, I'm not sure if we've gotten into in the first or second session is, I'll ask people, what do you call the person that graduates last in their class in medical school? Doctor. They meet the requirements. So does the first person in class. Well, they, that's from a question one perspective, those two doctors are absolutely interchangeable. I need a doctor. Well, what I ask is, is there a difference between those two doctors? And if there is a difference, when does that difference appear? And that's what you're talking about. From a question two perspective, the difference between those two doctors shows up when they walk into your room. They know when they're providing the whatever procedure you need, when they interact with you and your family, when they interact with other professionals at the hospital. The difference between any two things that meets requirements shows up when they, when all these things come together. And my excitement over Deming's work is he learned about that from Dr. Taguchi, who I learned it from.

0:14:47.1 BB: And what Dr. Deming did was integrate that sense of understanding variation and systems with the psychology of theory of knowledge of the system of profound knowledge. And that's provides an incredible theory by which to run organizations. That's the potential of 21st century quality that I hope we can inspire.

0:15:08.7 AS: And if I kind of try to piece together what you're putting out there, I think the first thing you're saying is that absolute interchangeability doesn't exist.

0:15:18.7 BB: No, no.

0:15:18.8 AS: Because nothing can be perfectly interchangeable. The other thing...

0:15:22.5 BB: If no two snowflakes are the same, if twins aren't identical, then you can't have absolute, absolute interchangeability. If you understand variation, it can't be.

0:15:32.9 AS: Okay, so then the next thing is that because we can't have absolute interchangeability, we need to understand some parameters or requirements and of what we need for this application. And then the other part of that is to understand that then there's variation even within, once you've set those parameters or requirements, there's going to be variations within that. Help me to continue to understand this.

0:16:06.4 BB: Well, first, let me give you an example outside of manufacturing just to make it easier to understand. So one is you put out a job search that you're looking to hire someone with these skills and 10 people meet the requirements. And does a given company take those 10 people and say, "Okay, put their names in a box, we're going to randomly pull them out?" I don't think so. We narrow it down. We take the ones that meet requirements. We call them up. We do an interview. What are we doing? We're sorting amongst things that meet requirements. Why? Because they aren't absolutely interchangeable.

0:16:50.3 AS: But when we're sorting amongst those, we're sorting, as you just described it, we're sorting by different characteristics like from the way they respond to something, or.

0:16:58.3 BB: Well, we're saying these... So we're saying these 10 people all meet the requirements of number of years of experience, a bachelor's degree, this and this. But now what we're doing is seeing through phone call, likely the scenario would be we're going to interview them by phone and get it down to three, bring the three in. What we're looking for is, what we're saying is those 10 are different. They all meet requirements, but they're different. And what we're looking for eventually is which one's the best fit. Why? Because fit is relative, not absolute. If fit was absolute, we would just roll the dice and say they're all the same. It doesn't matter. No, we don't do that. And like I say, I kid people, "Is that how we find a spouse? We just go to some dating app. We end up with three people. We say, this one?" No. We're looking for which is the best fit.

0:17:52.9 BB: So this idea of understanding fit as relative is an everyday thing. All the parking spots meet requirements, which is the best fit for what I'm doing that day? That's what we're talking about. And I mean, aside from manufacturing, it's the same concept. We're saying all the fruit is not the same. I want one which is about this juiciness. These applicants are not the same. What we're looking for is which is the best fit into the system of the product or the service or the company.

0:18:29.7 AS: And this discussion helps people to think about the idea that it's kind of nonsense just to think that by defining something kind of loosely, like I want this one inch long, as an example, that there's just so many flaws to that, that it's not the best way to do it. We need to understand more. What does it take away from this?

0:18:58.6 BB: Well, let me say this, because I don't want to make it complicated, but there's a time and a place for absolute interchangeability and moving on. We go to McDonald's, that's how they make their food. We're just saying, okay, I mean, I'm not saying absolute interchangeability, get rid of it. What I'm saying is use absolute interchangeability where it's not worth doing more than that. And then where it makes sense, whether it comes to staffing, a relative... And even in every feature of a product that you make, not every aspect of it has the same fit issue. So the big thing is, where fit is most difficult, or most important, that's where you apply the meaning of question two. So if it's not worth the effort, then you don't do it because the strategy is the amount of time I put into sorting the things that are good has to pay for itself.

0:20:06.9 BB: So I go through all that trouble when it comes to who I wanna date, who I wanna marry, where we're gonna have the reception, where we're gonna go on vacation, alright? But it doesn't mean we apply that same degree of effort everywhere. Again, when you're selecting a doctor, you might wanna go to that extent. When you're selecting an attorney, but the idea is that you can, as we've talked prior, is become aware that's it's a choice. Do we focus on question one, which is absolutely interchangeability. It's a very simple model. Does the application... Is it worth any more time than that? No. Then that's the way to go versus question two. Let it be a choice.

0:20:49.5 AS: So let's wrap it up by thinking about the listener here and saying, okay, they're gonna go back into their job after listening to this. And what part... What can they do with this knowledge? Let's say an exercise at work or a way of thinking about how this can help them in their everyday job.

0:21:11.2 BB: I think the big thing is, and it's very straightforward, I don't know how much work it takes, but pay attention to how people use what you give them whether it's data you're handing off in a spreadsheet. Last week I met with our CPA who does our taxes year after year. And for my business, I give him a spreadsheet with a bunch of different columns and rows, and every year I add a couple more columns and a couple more rows. And I cut and paste and put it into a PDF file and send it to him. And I was talking with him last week and I said," You know, Mike, I can put that in a spreadsheet. It's a little bit more work for me." Because I said, "How legible is that fine print?" And he said, "It would be helpful if you did that." I said, "Boom, I can do that. I'm gonna do that." But if I didn't know, I would keep sending it to him, and he's squinting, squinting, squinting.

0:22:14.1 BB: And that's exactly what I'm talking about, is pay attention to how people use your work. It's as simple as that. Going around the corner and just asking for more clarity 'cause then the question is, "Is it possible that with a little bit more effort, I could save you a lot more effort?" [laughter] And that's what we're looking for. And relative to our accountant, it's not that hard for me to cut and paste and send him a different spreadsheet. That's a few seconds, and I think I could save him a lot more than a few seconds. So that's... The big punchline is in the world of interchangeable parts, I just say, "Hey, this is good. It meets requirements." Now what I'm paying attention to is, "What if I put a little bit more effort in this, can I make your life easier?" And that's the essence of teamwork.

0:23:11.8 AS: Yep. Well, I think that's a good place to wrap it up, Bill. On behalf of everyone at the Deming Institute, I wanna thank you again for this discussion. For listeners, remember to go to Deming.org to continue your journey. This is your host, Andrew Stotz, and I'm gonna leave you with one of my favorite quotes from Dr. Deming: "People are entitled to joy in work.”