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"Inspecting quality in" is not only bad practice but a sure road to losing money. Deming's book Out of the Crisis is credited with the concept of Total Quality Control although he never mentioned it (probably because it was a buzz-word).In his 14 Key principles in the book, two are worth examining:

Bill Tobin

November 7, 2011

6 Min Read
Get rid of quality control

"Inspecting quality in" is not only bad practice but a sure road to losing money. Deming's book Out of the Crisis is credited with the concept of Total Quality Control although he never mentioned it (probably because it was a buzz-word).

In his 14 Key principles in the book, two are worth examining:

#3 states "Cease dependence on Inspection to achieve Quality. Eliminate the need for massive inspection by building quality into the product in the first place."

#10 states "Eliminate slogans, exhortations and targets for the work force asking for zero defects and new levels of productivity ........ as the bulk of the causes of low quality belong to the system and lie beyond the power of the work force"

His system was really simple - know what a good part is, be able to make it, and then make it. Period.deming.jpg

W. Edwards Deming

Yet when the Western World read his book, it spawned the fiefdoms of charts, graphs and exotic statistical measures couched under the veil of Japanese buzzwords and dozens of multiletter acronyms, not to mention legions of people on the payroll who cost money but didn't contribute anything to the profit margin. Further, it established a culture of explaining and justifying scrap using 'explainable variances' and other code words but what was interesting was even with these explanations nothing happened to eliminate scrap.

Let's look at two simple departmental labels.

QUALITY CONTROL is supposed to control quality. What's interesting is their normal operating premise - although they'll never admit it: "I know you're making unacceptable parts, and it's my job to catch you at it." This results in a game called 'hide the cheese' where, when a lot is rejected internally, production simply hides it and presents it for a favorable outcome to a more amenable inspector.

The conflicts here are interesting: (1) Why would two different inspectors give different opinions on accepting the lot? (2) If production is producing 'bad' product, why are they making it in the first place? And (3) Doesn't production know the difference between what is acceptable and what isn't?

The only conclusion that can be drawn is that nobody knows what an acceptable part is.

The job of QUALITY ASSURANCE is to assure the parts continue to meet some quality level. Their operating premise is, "We know you're making good parts, we are only checking for some variation that might make bad parts." This results in questioning the reliability of the mold and machine first, then challenging the assumption of a robust process.

Unlike Quality Control, there are no conflicts here - Quality Assurance is on the side of production to minimize scrap and maximize profits.

Getting back to Deming's two points:

- Eliminating the Need for massive inspections should be interpreted as first challenging the customer's definition of quality and what they are willing to pay for. The requirement of a CpK is usually an admission that the customer is afraid of the consequences of producing a part at the edges of the specifications. The statement 'free of manufacturing defects' is cute to include; but shows ignorance of the SPI cosmetic standards that are freely available to anyone.

- Many companies seem to think that inspections can take the place of maintenance (the second point in Eliminating the Need). Well designed/manufactured molds (not the cheapest) and well maintained machines that don't bleed oil all over the floor will give you a consistent part. Once you can repeatedly make the same part, all that is left is to develop a process that can be repeated in any other appropriately maintained machine (sometimes we call this Scientific Molding).

Deming's point (#10) is about making money, not adversarial departments with silly names (Master Molder, 6 sigma, PPM, zero-defect-Black-Belt-Quality-Ninja - really?) almost qualifying for custom made t-shirts and logos on hats so you can identify the armies on the field of battle. Look at your system - how many times do you start a job in a machine that isn't capable of producing the required quality level and then watch the complaints come in from everyone yet not holding the original decision maker responsible? How many multi-cavity molds do you have with blocked off cavities - have you adjusted the process sheet accordingly, why aren't you bringing it back up to full cavitation?

Does your 'system' include?

- Forceful efforts before you accept the job to get a crystal clear definition of the customer's expectations in writing?

- Preventative Maintenance programs on machines and molds?

- Capability testing of the machines to assure they have maintained the precision and accuracy you need to produce good parts?

- Operator training - real training - not just showing Bob or Suzy where the emergency stop button is? The operator should know when something is shifting and be able to do something about it. Well trained operators can be promoted into highly skilled techs. Trained operators make less scrap than just hiring warm bodies off the street. Does your training program include repeated ANNUAL training?

- Can your setup techs write a set of conditions that can run in any machine that will fit the mold and get acceptable parts without having to 'start from zero'? If they can't, they need to be trained.

Deming's 14 points are simple. We ain't in slap-and-bang manufacturing mode anymore. We can't afford waste, but more importantly, we shouldn't be inspecting quality either, doing this only condones bad manufacturing. The molding business is about making money. Money is made by selling acceptable product to those who are paying for it. Everyone's job (regardless of their job title) is to put those parts on the shipping dock or help someone who is. Helping doesn't mean laying blame, PowerPoint Slides, or confusing statistics. It means cleaning up 'your act'. Good people with good training and good tools will make you a ton of money. Sloppy will put you out of business.

You can justify not maintaining molds because they aren't yours, you can further justify not maintaining your equipment because you'll 'get around to it' sometime in the distant future. But you can't look me in the eye and justify why you aren't making an acceptable profit margin.

You can read this rant and maybe even download Deming's writing and see the elegantly simple logic he used to bring Japan out of economic disaster after WW II to a manufacturing powerhouse. You can do the same. Or, you can read this, smirk at it and say while good points are made, it doesn't apply to you. OR, you can read this and continue with your internal battle between customers, quality and production.

It's only the lifeblood of your company. It's your choice.

Consultant Bill Tobin [email protected] is a regular contributor to IMM. You can sign up for his e-newsletter at www.wjtassociates.com.

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