Shift from craftsmanshift towards engineering in manufacturing? 5

[MartinLe]

I have a hunch: Until a few decades ago, engineers would do their design, then in many cases the foremen or other skilled crafts persons on the shop floor would figure out what jigs to build etc. to manufacture something efficiently. Anecdotally this is confirmed by stories from one of my grandparents who was a master machinist/turner.

Then, with the arrival of CN machining going on to current robotics, the relative importance of master craftsmen (well, mostly men) etc. in the manufacturing waned, more of the actual manufacturing process was designed off the shop floor.

My question is if this hunch is basically or at least somehwat correct?

Mind, I recently read one article about modern chip manufacturing: The large foundrys (the example was in Taiwan) employ armies of (mostly young women) to do all sorts of manual tasks in the clean area, working 12 hour shifts without lunch breaks, because the production runs change so fast that they can't reprogram or redesign all the robots. Another recent article I read about a solar cell manufacture made the point that the US lead in research but that the technological advantage Japan gained stemmed from actually manufacturing PV cells (for wristwatches etc. at first)- the claim is essentiall shop floor knowledge helped secure the advantage. So only a relative shift, not an absolute one.

 

[MacGyverS2000]

The US lost talent because we decided to ship a lot of the work outside of our borders... I'm sure CNC exacerbated things a bit, but the majority is likely tied to the removal of the actual in-hand work from the factories.

And I seriously doubt that article about hip manufacturing was a US shop... you're just not going to find a shop here that has folks working 12-hr days without lunch like a sweatshop, particularly in the medical device field. Japan (or whomever) may have an advantage in a lot of areas, but you'd have to take them on a case-by-case basis... specific researchers, even. All it takes is a single breakthrough to allow a country/company/person to leapfrog past everyone else, at least for a time, and PV cells are no different.



Dan - Owner

http://www.Hi-TecDesigns.com

 

[JohnRBaker]

I agree with the idea that manufacturing leadership can move from country to country. Just go back 30 years or so and look at what happened with what was original referred to as 'Winchester disc drives'. Each time the industry moved to a smaller format, the country where most of them were manufactured seemed to move, which I guess is understandable since you had to tool-up for a totally different production line since the old ones couldn't be adapted easily or quickly.

As for the CNC issues, I also agree, because as companies started to install CNC machine tools, they also started to shut down their apprenticeship programs because management fell into this trap believing that they could hire anyone off the street to run a machine tool. After all, all the operator had to do was push a button, then stand there and watch the machine run.

I can recall how back in the 70's when our shop installed their first NC controlled sheet metal punch and forming machines. Up until then, when we designed a sheet metal part, we only made drawings showing the finished part in it's formed state. But eventually we lost that skill-set in the factory and we had to start adding a second sheet to those sort of drawings, showing the blank, unfolded or 'flattened' part.

John R. Baker, P.E. (ret)
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[TheTick]

I often refer to builds that require copious handiwork as "craft projects". One of my operative phrases is "Take the 'crafting' out of it."

This applies mostly to assembling small products, but applies broadly to other things. In my field, any part or operation that requires excessive fitup or "calibrated eyeball" needs to be refined. Sometimes it can't be avoided, but it must be minimized.

I started as a machinist. I used to take for granted others' ability to use tools and square up setups. So wrong, I was.

 

[JohnRBaker]

Yes, I can recall one instance like that. We had this machine, which was quite precise, that had a large part that moved up and down (it was a dough divider for cutting bread dough into the desired size pieces). Anyway, we had been manufacturing this machine for something like 30 years when all of sudden we get a frantic call from the shop that when they tested the last one built, it jammed. When we looked at it we noted that moving part had rammed into the head of a cap-screw. We looked at that drawings. Checked the parts list and what they had sent over from the stockroom and everything was as it had been specified. It was just that the height/thickness of the head of the cap-screw was too high and the moving part hit it. We checked and there had been no changes made to the design or the specified hardware in years, yet dozens of those machine had been manufactured, shipped and were in production at our customer's bakeries, all with no problems.

Well it took awhile to figure what had happened. First off, the guy who had been assembling these machines for the last 20 years or so had recently retired and another guy had been given his job and that's when the problems started. Someone decided to call the retiree up and asked him to come in look at what was happening. As soon as he saw it, he went over to his old tool box and in one of the drawers he pulled out a couple of cap-screws and told them to use these instead. It seems that about 10 years ago, someone made an engineering change and specified a different type of cap-screw, which had a higher/thicker head and the first time this guy assembled it, it jammed, but rather than telling engineering about it, he simply took the cap-screws over to the machines shop and had someone mill off enough of the head so that there was adequate clearance. After that, whenever he started to assembly a new machine, he would take the cap-screws that were sent over from the stockroom and have them milled down. In fact, he would sometimes get some extras from the stockroom and get them milled-down so that he'd have them ready when he needed them, always having a few in his tool box for the next machine. He was very proud of himself for being so resourceful, only regretting that he failed to tell the guy who took his place about the 'special' cap-screws he had made.

Of course, we changed the parts list to include a low profile cap-screw, which we should have done years before. However, it was a good lesson, if for not other reason than to confirm that the CAD system that we had recently installed, if it had been around 10 years before and if the designer had tried to make the drawing with that particular cap-screw, he would have seen the interference right off the bat, at least that's what we told ourselves would have happened.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
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The secret of life is not finding someone to live with
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[drawoh]

MartinLe,

I am working on an article about aircraft technology in WWII. The Germans and Japanese manufactured their weapons with American tools. As noted above, tool manufacturing has shifted to another place. The next big war will be fought with weapons made with Japanese tools.

--
JHG

 

[MintJulep]

All driven by profit.

The master craftsmen were replaced by recently graduated industrial engineers who where neither crafty nor masters (nor unionized).

The journeymen's jobs were offshored.

Here we are.

 

[IRstuff]

The master craftsmen were human, subject to being human and subject to larger variabilities. There's an apocryphal story about the transmission Ford bought from Mazda; they were all so tightly built to specification that Ford's "master craftsmen" could do their usual "mix & match" to account for all the slop Ford's production had taken up, resulting all the delivered transmissions being unusable for Ford.

I've been in shops where "production" resulted in "snowflakes" with each unit being different in a different way than all the other units.

TTFN (ta ta for now)
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[SnTMan]

Sure, you don't want them to be necessary for quantity production, but without some presence of these master craftsmen and the culture around them an organization stands little chance of developing real manufacturing know-how. IMO.

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[TheTick]

I believe in a Newtonian-style conservation of competence. It takes x amount of brainpower to make something happen.

If you want something to be easy to assemble, the designer will need to sweat the assembly details and the parts all need to be perfect. If you have sloppy parts, the assembler will have to get "crafty". If you want perfect parts to just poop out of a mold, a lot of sweat goes into the design of both the part and the tool, and the tool needs to be well-crafted.

As they'd say in the US Navy: "Designed by geniuses to be run by idiots."

 

[drawoh]

IRstuff,

According to Arthur Herman in Freedom's Forge, Ford and GM production expert Wilhelm "Bill" Knudsen told the American military that precision was a critical part of mass production. All subcontracted parts had to fit. He went through the Ford and GM assembly shops and he threw out the hammers and files. They were not to be needed.

--
JHG

 

[JohnRBaker]

If you want perfect parts to just pop out of a mold, a lot of sweat goes into the design of both the part and the tool, and the tool needs to be well-crafted.

This describes how LEGO has managed to maintain their level of quality and the loyalty of their customers. I've worked with the people from LEGO as they use our CAD software (when I was still working for Siemens) to design and manufacture their tooling, some of the most precise and consistent of any company in the world. And when I say consistent, I mean, just take one of those basic LEGO bricks that you may have bought your kids way back when (we bought our boys their first LEGO sets in 1974), and then buy some new set today and try and snap one of those new parts onto that old brick. You will see what precision means, not necessarily with respect to the design of the bricks, which is pretty interesting in and of itself, but in the quality of the tooling which produced those bricks, be it the newest ones or that one from over 40 years ago:

December 1974 (Minolta 600-X)

Note that our son, John Jr, in the picture above, is now 51-years old, and we've probably still got most of those LEGO bricks in a big Tupperware box somewhere in the garage.

I've been to the LEGO plant in Denmark on several occasions and going into their tool room to see how the tooling is built and then going down on the production floor where bricks are being molded literally 24/7 in basically a 'lights-out' facility is amazing. I've also had been to the original LEGOLAND in Billund, Denmark, a couple of times:

May 1993 (Minolts XG-M)

May 1993 (Minolts XG-M)


John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[MartinLe]

I corrected a typo in my OP. It was, of course, a chip manufacturer.

I like the story with the milled of of screws.

The quality and quality control is pretty impressive with lego, and a good way to see is to get a knock-off.

 

[berkshire]

I discovered a "Marked up print problem" while working for GD . Towards the end of their time working in San Diego, the company started farming out jobs that were done in shop. This particular job was making the Z sections for the fuselage rings for DC10 and MD11 airliners. The pieces in question were rolled on a multiform roller to the Z shape then stretch formed to contour. So now an outside company gets the job of rolling the Z sections, they are checked to the drawing and found to be correct. The first pieces are stretch formed, and come up about 1/8" to 3/16" small. I mention to my boss that we may have to go back to rolling our own. He says we can't do that ,they have sold the roller. We go down to where the roller was and fortunately find the shop foreman's desk, Inside was a set of marked up prints for all of the fuselage rings showing how much to add to the Z so that when it is stretched the dimensions come right. These were handed over to the drawing office and all of the drawings were "corrected" and re issued. The parts then formed perfectly. I made a comment about using marked up prints. My boss said " Would you believe they have been doing that since 1969 and nobody knew.".
B.E.

You are judged not by what you know, but by what you can do.

 

[enginesrus]

The mention of WW2 aircraft manufacturing makes one think. In various books about the design work in those days, all the great planes or engines that came about, the only people that get credit for the accomplishments of bringing that machine into operation are the management and engineering people. The forgotten ones are the machinists and mechanics that most likely are the ones that "cut the bolt" to the correct size to make it work, or ran to engineering and said "what were you thinking, this will never work", some times the real engineers are wearing coveralls covered with oil and dirt. Think Smokey Yunick the engineer that many auto manufactures went to for help.

 

[CWB1]

Until a few decades ago, engineers would do their design, then in many cases the foremen or other skilled crafts persons on the shop floor would figure out what jigs to build etc. to manufacture something efficiently. Anecdotally this is confirmed by stories from one of my grandparents who was a master machinist/turner.

Sounds like you've mistaken an individual's unique experience for common history. SME was originally founded as the ASTE (tool engineers) in 1932 and industrial engineering was already a long-established field unto itself by then. Decades ago companies often would allow senior tradesmen to become designers in some limited capacity, but many companies still do today so there's nothing really remarkable about it.

Asia's two defining competitive advantages in manufacturing still today are their lack of regulation of labor and the environment. If they had to treat those two as the US or Europe does then there would be no advantage and likely little competition bc given equal opportunity, a mass of labor using old-fashioned techniques usually cannot compete with modern technology.

 

[SwinnyGG]

There's a major disconnect here...

Designing things well 'off the shop floor' does not mean craftsmanship is gone from the process; it just means that craftsmanship is done by people who look different and use different tools.

Problems that result when things are assembled exactly as designed and still don't work are design problems - and are emblematic of a lack of craftsmanship in the design process.

What does the word 'craftsmanship' really mean? It means a certain level of pride in the quality of work, attention to detail, and application of knowledge gained over long experience. Good designers are craftsmen, even if their tools are pen and paper (or, now, mouse and touchpad) instead of files and rasps.

Removing the craftsmanship ethos from the work means negative results, whether the collar of the craftsman is dark blue or light.

 

[IRstuff]

I think Martin is actually referring to artisan-ship(?). There was a brief, shining, moment in history when the Japanese ate our lunch with craftsmanship manufacturing, where they followed the teachings of Deming, while US manufacturers were more interested in squeezing every penny of profit by allowing manufacturing tolerances to be sloppy and to have sloppy quality.

I've told this story many times in these forums, but I'll repeat it here again. We once had the occasion to second source a part from Hitachi that was a second source of an originally Motorola part. We get the photomasks for the chip and there are ZERO test chips on the mask; WTF? we always have test chips to monitor for process deviations and outright failures. So we call up the Hitachi engineers, and they say, "Don't worry, we don't need test chips, and they suck up 5 prime positions on the wafers and that costs yield." "OK," we say, "but you didn't provide any process run recipes, so how are we to know what oxidation times, ion implant doses, etc.?" They go, "Don't worry, just run your standard process, and it'll be fine." Dubiously, we run a lot through, and the wafers yielded 120 die per wafer, which was about 50% higher than anything we had run with parts designed specifically for our own process. The second lot yielded more like 130 die per wafer; even better.

THAT is craftsmanship; designing a chip that didn't need process monitors and could tolerate whatever crap our process engineers might throw at it, intended or otherwise. THAT was what Deming was trying to get through to us, but we thought it was a bunch of kumbaya and BS. It was at this point that I thought I should seriously think about learning Japanese. Fortunately, or unfortunately, 3 years later, the Japanese buying spree of US properties bit them HARD, to the point where it took their economy more than a decade to recover, while ours took less than about 2 years.

TTFN (ta ta for now)
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[drawoh]

IRstuff,

There was a nifty article in Design News back in 2005/10/10, The Quest for Imperfection. The article presents us a picture of Orientals being inscrutable, and not understandable by us. I claim that somebody in Japan is specifying manufacturable tolerances. The designers are doing whatever they have to do to make the as[ ]toleranced parts work, and the manufacturers are hitting the specified tolerances. There are multiple ways your fabrication drawings can be crap, and they all cost you money.

You send a drawing package to Billy Bob and Cousin Elmo's sheet metal and welding shop. They know they will spend four hours in screaming matches over the phone with you. They know that 20% of the parts are going to be returned for free re-work.

Surprise! there is no free lunch. Billy Bob and Cousin Elma need a predictable process in which they get paid. They can always refuse the business.

This does not directly reflect your wafers. In design and manufacturing, you do need to stand back and see the big picture. Money saved in documentation and manufacturing, costs you in assembly, and in warranty repairs. My reference to Bill Knudsen, above, is an example of Ford and GM experience in the teens and twenties that perhaps did not make it through the fifties.

--
JHG

 

[JohnRBaker]

The goal in design and manufacturing is to fabricate your parts with the loosest tolerance which will result in your assembly performing as desired. The only result of using tolerances which are 'tighter' then necessary is to increase the cost of the part. Now that being said, the job of the designer is to know which are the critical tolerances and which are not. This is where modern tolerance analysis software which uses procedures like Monte Carlo simulation which will allow you to determine which tolerances on which dimensions/features have the biggest impact on assemblibility and functionality. Once you know which are the critical tolerances, you can then specify the least expensive method(s) for manufacturing each part of your assembly.

John R. Baker, P.E. (ret)
Irvine, CA
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