Quality countdown

Author Cutting Tool Engineering
Published
June 01, 2012 - 11:15am

An industry veteran examines the top 10 issues for maintaining and enhancing quality control in parts manufacturing.

Editor’s Note: LaRoux K. Gillespie is a noted consultant and writer on manufacturing and quality issues. He retired in 2006 as a second level manager in Honeywell’s Kansas City, Mo., division, responsible for all plant product quality issues and practices. He worked for the company and its predecessors for 40 years. He is currently president of the Society of Manufacturing Engineers.

All businesses strive for quality—their success and reputation depend on it. In precision parts manufacturing, attention to detail is especially important, so continual attention to quality should be of utmost concern. It’s amazing how many shops, no matter the size, skimp on training or just coast when everything seems to be going well.

Throughout the years, I have experienced a variety of quality issues. While many of these are now controlled by ISO 9000 or similar certifications, not every shop lives by these international practices, and those that do still face some “hidden, under the blanket” issues. Here are the 10 quality issues most important to me.

1. Documentation

To achieve consistent quality, manufacturers must rely on documentation of what they want, how they intend to get it (work instructions and other procedures) and what they have to work with. While this seems simple, in many shops it is only partially achieved. Work instructions are not complete enough to assure conformance by every employee on every shift. For example, Joe has his little black book of details that are not in the work instructions, and Tom has his own book—and the details are different.

ISO reviewers never see these undocumented records. Rework is not documented. Inspection results are not fully described or recorded. Beyond that, the procedures for many tests and “quickie” evaluations are not fully recorded because engineers and shop staff generally do not like to write. 

Then, finding such results a few months later proves to be difficult because if you don’t have clear rules on documentation, you probably don’t keep good records of notes either. Documentation does not necessarily require lengthy manuscripts—photographs, sketches and other images are often more descriptive and readily produced.

A good documentation system begins by identifying the source of the information (person or organization), the purpose (just archival or expected to be used routinely), and the date of the information. The documentation system should also provide ready identification that the document exists and where to find it. Lastly, the staff must know that documents are routinely stored in the system; they need to be trained on the details of the system and how to use it (see next item).

2. Training

It’s astounding that some shops introduce workers to new positions without any training or with training that is inadequate, late or undocumented. It happens in large, medium and small plants, and in plants with outstanding quality credentials. This problem only gets worse as skilled workers leave the workforce and new, often underprepared, ones replace them.

Every employee enters a company with a different level of training and understanding (some may have received the same training, but that doesn’t mean they fully grasped it at a working level). Companies generally do not have a program that fully assesses a new employee’s technical abilities and comprehension.

The variety of machine controls in each facility means operators need more training on individual machines as well as on general shop practices. Shops need a formal outline of hands-on training topics; otherwise, something will get lost that can be critical to quality.

A number of online training courses are available for shop positions, and engineers are taking advantage of them because they are underprepared for immediate job output. Tooling U (www.toolingu.com), for example, has about 50,000 students taking online training through companies or local high schools and community colleges. 

The U.S. government’s push for community colleges to be a major source of workforce training will lead to more reproducible training. The Manufacturing Institute’s Manufacturing Skills Certification System and National Institute for Metalworking Skills (NIMS) certification levels provide the credentials for hands-on skills, and others provide certification of engineering and other technical knowledge.

Companies should still define the training needed and provide it, or work with community colleges and technical universities to get workers on the right track. In many areas, coalitions of companies are working with schools to assure an adequate supply of skilled workers. Companies also need to maintain a list of necessary training for their employees and keep it updated.

3. Adherence to Procedures

Documentation and training do not assure quality unless workers adhere to procedures and expected practices. The ISO 9000 assessment teams that monitor conformance every 6 months almost always find nonconformance when reviewing a shop. Most problems are corrected immediately and an embarrassed shop management reiterates a need to consistently abide by procedures. But adherence is not just a shop issue. Engineers are often guilty of the failure to abide, as are managers, inspectors, HR staffers and others.

Lack of adherence comes in many forms: intentional, lack of training, lack of understanding or plain forgetfulness. Whatever the reason, it occurs frequently and can lead to major quality problems. 

Management must continue to focus on adherence by commending employees rather than just admonishing them. Continued adherence is also a measure of how well employees and management work together. Close working relationships breed a desire to adhere whenever management encourages such behavior.

4. Fudging

As the word is used here, saying a worker “fudges” results is a polite way of saying he has poor ethics. Every time we stretch the rules or bias (fudge) the reading to be within allowable limits, we begin the slow and painful drop to lower quality. For example, being 0.000050" over the limit is not much when the tolerance is 0.005", but it is still outside the limit. Because many customers sample only a few parts out of a lot to measure conformance and assume the rest are the same, they probably won’t see it. Their measurements might not even be that precise. But the parts are still out of tolerance.

Once handled that way the first time, the event will likely be repeated. As soon as employees notice management allowing this practice, they will follow suit and the practice spreads. It is essential to consistently live within the rules and procedures and to acknowledge successes and failures as they occur. Slight fudging is nonconformance!

5. Continual Assessment

When nothing bad happens, it must mean everything is fine—right? When everything’s running smoothly, we get comfortable and relax our efforts somewhat. Such laxness allegedly led to the catastrophic failures of the space shuttles Challenger in 1986 and Columbia in 2003 and the BP Deepwater Horizon oil spill in 2011. In all three cases, there were several clues beforehand of problems that could have been identified and addressed through continual quality assessment.

QA requires listening to employees regarding current issues, unexplained differences and trends. Management via “walking around” the shop still works if you listen for things that don’t sound normal. Employee frustrations, fatigue and irritability are also signs of impending quality issues. Detecting issues before they get to be problems often occurs when things are going well—which is also a great time to commend staff when they adhere to procedures.

6. Tools

There are many convenient QA and QC tools available for companies of any size to readily apply. Failure to use them or be cognizant of their existence can make quality inconsistent. Lean manufacturing tools provide simple visual and manual tools. Statistical process control programs are widespread. Six Sigma still works. Shingo’s SMED (Single Minute Exchange of Die) system still makes 1-minute setups fast and mistake-proof. Failure Mode and Effects Analysis (FMEA) prevents failures. Risk analysis identifies the issues that might unexpectedly impede quality. In-process monitors are widespread and relatively inexpensive for high-production operations. Today’s machine controls come complete with sensors that foretell impending failures and equipment wear. All of those tools identify present or potential issues affecting quality and are applicable to shops of any size. 

7. Complaints

Complaints are a pain because they get in the way of “real work.” However, they provide an ideal opportunity for management to make major improvements in the perception of company quality. Every employee complaint heard inside the shop is a clue that something is not right (i.e., quality might become an issue).

Complaints about equipment, tooling, material delivery, instructions and communication are potential quality issues. Complaints about the boss and management might or might not be a potential quality issue as well. (To fix that issue the author suggests reading Jack Stack’s “The Great Game of Business.”)

Potential customers’ impressions of shop quality can be based on complaints found and shared through social media. In less than 24 hours, a company can find plenty of negative comments posted about them, some of which can be the result of a single complaint that multiplies. Positive impressions about quality can just as rapidly appear online by companies that know how to effectively use social media.

8. Communication

Miscommunication between shifts and between individuals also can lead to quality issues. My company once had a lot of parts enter inspection without deburring. The first shift left a note for second shift saying “deburr complete.” Because deburring was complete (per the note) the supervisor submitted the parts to inspection. However, first shift was trying to say, “You need to deburr these parts completely.”

Fortunately, this did not cause a serious problem because the error was caught before the product left the plant. Clear instructions and clearly marked areas for completed parts, inspected parts and parts with issues prevent most of these problems—but as a married guy talking to my wife, I still find I frequently need to more clearly state what I really mean. Be clear in your communication. Stop and think how others may interpret your comments.

9. Clarity

Clarity and communication go hand in hand, but in this instance we differentiate the two by referring to work instructions. Many shops rely more on photos and sketches than just words to get the intent of their message across. Images transcend language and reading ability. Pictures with identifications on them simplify and clarify instructions. It is one of the underlying features of lean manufacturing. Pictures show where and how and can show when. Images are easier to comprehend than written instructions. Appropriately done, pictures prevent mistakes and enhance quality. They reduce risk for inspection and for manufacturing.

10. Management Change

In my career, I purchased precision parts from many machine shops. I found that a number of quality problems occurred when shop management changed. Typically, we would spend several months working with a supplier, and their quality performance would be excellent. Later, quality issues would begin to appear. After a visit to the shop, we would often find there had been a change in its quality management chain.

That change altered the shop’s practices, which affected our incoming quality. The change might involve training, increased emphasis on production rates or cost cutting. 

If you find yourself in this situation, personnel changes are one of the first things to ask about. It does not have to be a change in management; changes in skilled workers can be just as devast-ating as management directives that subvert QA.

Each of the quality issues I’ve outlined here can be effectively addressed, but that commitment begins with management. Quality can change quickly—for better or worse—based on the decisions made by management. For the sake of your operation, make sure that your management team is on the right side of this equation!

What’s on your “top 10” list? Make a list and decide whether you have the right solutions in place. Feel free to share them with me at the e-mail below. Continuous quality is all about continually looking and asking. CTE

About the Author: Dr. LaRoux K. Gillespie has a 40-year history with precision part production as an engineer and manager. He is the author of 12 books on deburring and more than 220 technical reports and articles on precision machining. E-mail: laroux1@earthlink.com.

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    Number derived from the net increase in the depth of impression as the load on the indenter is increased from a fixed minor load to a major load and then returned to the minor load. The Rockwell hardness number is always quoted with a scale symbol representing the indenter, load and dial used. Rockwell A scale is used in connection with carbide cutting tools. Rockwell B and C scales are used in connection with workpiece materials.

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    Any manufacturing process in which metal is processed or machined such that the workpiece is given a new shape. Broadly defined, the term includes processes such as design and layout, heat-treating, material handling and inspection.

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    statistical process control ( SPC)

    Statistical techniques to measure and analyze the extent to which a process deviates from a set standard.

  • tolerance

    tolerance

    Minimum and maximum amount a workpiece dimension is allowed to vary from a set standard and still be acceptable.