Patty was wrapping up a few things before lunch. Her company, ACME, had just received a large order for the new Druid cellphone and she had responsibility to develop a scale up plan to assemble 3 million units a month.

ACME had received this contract by beating two assemblers from China. This win only was possible because of the work her team had done on the very high uptime lines. This high uptime allowed ACME to come in with a competitive quote that was more attractive than the Chinese companies. With the added advantage of not having to ship the Druids from China, and fewer IP (intellectual property) concerns, ACME got the contract. It was a major feather in her cap. But now she had to deliver.

The customer even had given her a new Druid phone. It was very impressive, but she wondered why they named it after such mystic people. Oh well, she thought, this just confirmed that she should not be in marketing.

As she was wrapping up, she checked her email. She saw an article on one of the online trade journals: Netbook Sales Are Crashing! Quick! Blame The iPad, Not The Lousy Netbooks! . She was curious, so she read it. The article began:

Well what do you know? Netbook growth is so low right now that in a recent report by NPD, Morgan Stanley Research lists last month’s growth as a negative number. That’s right, people are apparently selling the notebooks back or something. (Not really, but no one is buying netbooks right now).

Looking at the graph, she thought a more appropriate title would have been: “Despite launch of the iPad, netbook sales reach all-time high in July.” After finishing the brief article, she went off to lunch.

Patty was glad that, even after her promotion, her lunch friends still felt comfortable with her as part of their daily friendly ritual. As she approached the lunch table she heard Phil and Rob arguing.

“Rob, I’m telling you, I read it on line, Netbook sales have crashed, they have essentially gone to nothing almost overnight,” shouted Phil.

“But our plants in China are making just as many as they were in July,” Rob shot back. “I should know, its part of my job,” he finished.

“Patty, they are fighting again. Can you break them up?” Jan Curtis teasingly implored.

“Hey guys, what’s going on?” Patty asked.

“It’s your hubby again, he doesn’t recognize that an important part of his business is gone. I saw the graph,” Phil answered.

“I saw it too,” said Patty, “And, if you study it, I think the author was mistaken or misleading.”

Patty brought the article up on her new Druid phone. The resolution and size of the screen was so good that it was easy for everyone to read the graph and the article. She handed it to Phil.

“Phil, look at it closely and see if you don’t think the author made an error,” Patty said.

Phil looked at it for a few seconds and then became a little red in the face. He handed the Druid to Rob.

“Yikes, I’m embarrassed. It was the growth rate that tanked. The absolute sales only went down 4% in August. July was a record month,” groaned Phil.

The cell phone got passed around the table and everyone read the article.

Pete Wilkins summed it up, “Netbook sales may be down a little in August, but no data support their sales crashing. This might become the case in the future, but we can’t tell from the data provided.”

Epilogue: As Patty walked back to her office and settled into her chair, she once again looked at the article on her Druid.  What she saw caused here to just about drop the Druid.

The graph did not say “Netbook,” it said “Notebook.”

“Double yikes!” she thought. “The author not only got the numbers wrong, but got the product wrong.”  She followed the links to the source article and saw that the entire article was about notebooks, not netbooks!

Au. note: We should be data-driven in the decisions we make at work, at home and in our lives. Few things are as important. So I feel that it is helpful to point out the misleading nature of articles like the one referenced above.
Cheers,
Dr. Ron

Folks,

Answers to the quiz of a few weeks back …

Phil and Rob had agreed to ask the GM if it was OK to ask the tech and engineers at some of their subcontractors to take the test anonymously. Over a period of two months Phil and Rob got 52 people to agree, almost all of them after Phil or Rob agreed to take them to lunch. They asked Patty to grade the “exams.” Today Patty would reveal the results.

“Phil, this is one of the best bets I have ever made,” teased Rob.

Everyone at the lunch table chuckled, but the look on Phil’s face said he expected to lose. Rob has said that he thought the average score would be less than 70%, Phil insisted that it would be greater than 85%. In asking the different folks to take the test, invariably Phil started asking questions not on the test. He was surprised that no one knew what tin pest was. He even asked how to time balance a chipshooter and flexible placer, only one in 20 knew.

As Patty approached the lunch table, the ensemble held their breath.

“OK, Patty, tell us the bad news,” Phil said in a resigned tone.

“Rob wins, the average score was 58%,” Patty said getting to the point. “Here are the answers and percentages on each problem,” she went on:

1.    What is the composition of SAC305?
96.5% tin, 3.0% silver, 0.5% copper. 60% got this right.

2.     What are tin whiskers?
Tin whiskers are metal whiskers that can “grow” from tin plating on component leads. They are mitigated by 2% bismuth in the tin, a nickel overplate of the lead copper, a matte tin finish, and a few other mitigation approaches. (40%.)

3.    In a stencil aperture, what is the area ratio?
The ratio of the area of the aperture opening divided by the area of the side walls. This ratio is typically used for circular and square apertures. It is equal to D/4t, where D is the diameter of square side and t is the stencil thickness. (40%)

4.    What is an approximate peak temperature for a reflow oven in lead-free assembly?
Any answer 235° to 250°C accepted. (90%)

5.     A board is inspected after wave soldering and one lead is not soldered to the board. The board is run through the wave solder machine again and has the same defect on the same lead. What is the most likely cause of the defect?

a.       The solder temperature is too low.

b.      The pad on the board is oxidized.

c.       The preheat temperature is too high.
(b. 70%)

6.     What are local fiducials on a PWB for?
Local fiducials are located near the pads of a component with fine lead spacings to ensure accurate placement. (70%)

7.     What does “thixotropic” mean in regard to solder pastes?
The viscosity decreases with increasing shear stress. Hence, during printing the viscosity drops as the paste is forced through the aperture, aiding good aperture fill. It increases as the printed deposit rests, minimizing slump. (20%)

8.     A chipshooter places passives at a rate of 36,000 per hour. It is placing 300 passives on a PWB, how many seconds will the chipshooter take to place the passives on one board?
300/36000 = 1/120 hr = 30 seconds. (90%)

9.     A reflow oven belt speed is 100 cm/min. The PWB is 40 cm long. What is the minimum cycle time that the oven can support?
The amount of time that the belt needs to cover 40 cm is 40/100 = 0.4 minutes = 24 seconds. This is the minimum cycle time the oven can support. (40%)

10.   What is “tombstoning”?
Tombstoning is observed when a passive component’s terminations experience unequal wetting forces strong enough to lift one end of the passive so that it looks like a tombstone. (60%)

Overall average score: 58%.

“Wait a minute Patty; your answers are too demanding,” Phil shouted.

“Calm down Phil, I gave full credit for anything close,” Patty responded.

In unison, almost everyone at the table sighed, “Yikes.”

Patty interjected, “One person who received a 70% commented after completing problem 9 said, ‘I didn’t think I would need a Ph.D. in math to do this quiz.’ ”

All agreed that organizations committed to electronics assembly education, like the SMTA and IPC ,were more needed than ever.

Cheers,

Dr. Ron

Folks,

I was in the Dartmouth College computer store in 2004 or 2005 and I saw a signed that proclaimed: “After July 1^st computer services will no longer support Apple Macintosh.”

By 2008, however, I noticed more and more of my students using Macs. This trend was important to me as I use Minitab software in two of my classes. Newer versions of Minitab only support Windows.

This year, so many of my students use Macs, that I have to hold the classes in which I teach Minitab in the engineering department’s computer lab, as I want the students to follow me on a computer.

I was recently told that 75% of the incoming freshman at Dartmouth will be using Macs. All of this in spite of Macs significantly greater cost over a Windows based PC.

Since the students at our colleges and universities will be tomorrow’s leaders, this may portend big changes ahead in computing.

Cheers,

Dr. Ron

Rob bolted upright in bed. He had that terrible feeling that he had overslept for an important appointment. His eyes quickly found the clock and it said 10:30!

“Wait a minute!” he thought, “It’s Sunday.”

He looked a Patty peacefully sleeping and decided to let her sleep. They had had a tough two months. Ever since they proposed increasing uptime to greater than 60% on two “experimental lines”, they were working 90 hour weeks. They just felt they needed to constantly monitor two lines, to assure that things were going smoothly. They felt satisfaction that they achieved 68.8% uptime in a two month period, compared to the company average 30.4%, which is still very good.

The local newspaper got word of this effort and did a story on Rob and Patty’s work. The article was well written and very complimentary to both he and Patty, as well as ACME. Sam Watkins, the site general manager, was very pleased with the good PR. The accompanying photos were really nice too.

The big shocker came this past Tuesday. 60 Minutes wanted to do a segment on “The US Competing with the Far East in Electronics Manufacturing.” In agreeing to be interviewed, Rob and Patty insisted that members of their ACME team be included. In addition, they felt it was only fair to include the efforts of Rita from their stencil printer and reflow oven supplier, and States, their colleague from the component placement company. And they couldn’t forget Eric, from ACME’s prime solder paste supplier. These three folks helped Rob and Patty and their team to develop the plan to achieve the 60+% uptime.

An even bigger shocker came when the 60 Minutes crew told them that Andy Grove would be in the segment because of his recent article in Business Week, “How America Can Create Jobs.”

Grove insisted that to participate in the piece, he wanted to visit ACME to see what Rob and Patty were doing. So the 60 Minutes crew was visiting ACME’s plant this week as were Rita, States, Eric and now “Andy.”

“Maybe we should call him Mr. Grove,” Rob thought.

Rob had suggested that he and Patty go to Berdick’s in nearby Walpole, NH, for Sunday brunch and then to play golf. Rob had to chuckle, it was mid July and he and Patty had played golf 27 times (she kept a spreadsheet). He had beaten her 14 times and she was miffed. Even during their 90=hour weeks they would take three breaks a week to play 9 holes.

On Monday they were meeting with site GM, Sam Watkins, to discuss what they would tell 60 Minutes.

Rob and Patty’s Sunday was delightful. The brunch was delicious and relaxing and they both golfed well, Patty’s 68 beating Rob’s 69.

It seemed like no time at all and Rob and Patty were in Sam’s office.

“Just assure me that this 60 Minutes thing is not some expose that will embarrass ACME or put me in jail,” he teased.

Patty took the lead and explained what they had done. They trained the operators on the importance of line uptime, they worked with Rita, States, and Eric to develop a plan to assure that there would be minimum unscheduled downtime. They had to order extra spare parts and solder paste to assure no stoppages due to parts or paste shortages. One obvious thing is that they would be using two times or more the normal amount of solder paste. The two lines in the high uptime experiment had an average of one change over per day, consistent with ACME’s business.

They also increased routine maintenance on all machines. Both this maintenance and added spares was an increased cost, but these costs were second order effects compared to the dramatic profit increases due to almost 70% uptime.

Preparation for the next three jobs for each line was meticulous, so that setup time was minimized. Feeder racks were used extensively in minimizing setup time for changeovers. In addition tape splicing was employed to minimize any assist time for component placement. States’ help was crucial in the component placement part of their efforts, Rob pointed out.

Patty went on to describe how Rita helped them in their efforts to develop minimum assist times for the stencil printing process.  The reflow oven presented the least concerns in assist or unscheduled downtime.

The solder paste they selected was robust in that it had a very good response to pause, excellent tack, and minimal slump.  The paste also had the best track record for minimizing defects like head-in-pillow and graping. Eric also participated as an enthusiastic partner in the effort.

Patty mentioned that their colleague, Phil, had agreed to monitor uptime for two standard lines during the two month trial to compare downtime metrics to the high uptime experiment. These would be experimental “controls.”

She then showed the uptime data for the two high uptime lines and Phil’s control lines. The control lines had ACME’s respectable 30% uptime, but the high uptime lines had almost 70% uptime. Rob went on to explain all of the things the team did to minimize downtime, most of it was common sense. Sam was especially interested in one downtime category.

“What is floundering time?” Sam asked.

“That is time when the line is not operating due to some unplanned error,” Rob answered.

“Can you give an example?” asked Sam.

“Sure, you know how we have a quite organized approach to setups?” Rob responded.

“You mean our use of white boards to write down all of the things needed for the next three jobs on each line?” Sam came back.

“Yes, that is one of our biggest sources of floundering time,” Rob replied. “Someone will write that they have the stencil for the next job, when they just think they know where it is. When it comes time for that job the stencil cannot be found and an hour is lost.”

“Phil also noted a case where a job was finished on a line at 11:15AM, since lunch was at 12 noon, the changeover for the new job was not started until after lunch. Forty-five minutes was lost, forever,” Patty added.

Sam gulped.

“So we are losing more than 25% uptime to ‘floundering?’” Sam weakly asked.

“According to the Professor, it’s endemic in the industry,” Patty interjected. “He coined the term, ‘Floundering time’.”

Sam then mentioned how the “bean counters” at ACME were impressed with the two high uptime lines. ACME’s CEO wants a concerted effort to transition all of ACME’s assembly lines in North America  to higher uptime performance. Manufacturing in North America would also mean no two to four weeks of transportation time from the Far East. Patty, Rob, and their “team” were to form a new group in ACME to do this. Patty would be director of the group.

As the meeting was about to close, Sam asked what surprises Patty and Rob had during this experiment.

Rob then shared, “It relates to floundering time. We found that even among the engineers, no one appreciated the value of one hour of production time. We asked a group of operators what an hour of production was worth and the figures ranged from $50 to $500. ACME runs two shifts at 30% uptime; that’s about 1500 hrs per year. Our typical line produces $30 million per year; that’s $20,000 per production hour. When we told the operators this, floundering time dropped significantly.”

Patty added, “The other thing we saw is that a “watchdog” is needed. If someone isn’t constantly watching things, floundering and assist times will go up. Since productivity is doubled with a high uptime line, the added cost of a watchdog is insignificant.”

Epilogue: The 60 Minutes segment was a great success. Patty was made director of corporate productivity, but was also asked to manage Pete, who would take over her old group. No one seemed to worry that Patty was Rob’s boss, except maybe Rob!

Cheers,

Dr. Ron

Patty had just finished some emails and was ready to head off to meet Rob and some of their buddies for lunch. When she and Rob returned from China a month ago, Sam, the site GM, told them he was giving them an extra week of vacation for their honeymoon. Their China trip had been an unqualified success in helping the local teams achieve more productivity and higher yields. Sam had received numerous positive reports from the Chinese managers involved.

There were several requests to have Patty and Rob stay a year in China to help with the many process issues that the China team has. Fat chance of that happening, Sam needed Patty and Rob here! Sam also mentioned that he knew that the trip was a little stressful coming so close to their wedding, so the extra week was ACME’s gift to the young couple for their sacrifices.

The wedding went off without a hitch. Patty was touched at how choked up her dad was in “giving her away.” The wedding reminded Rob and Patty how close they were to their parents. They both agreed that the support of their parents was crucial in any success that they had in life.

For their honeymoon they decided to tour France, Italy, and Germany. Rob was really proud that he handled the languages a little better than she did. Of all the things that they saw, they were most impressed with Pompeii. Because the city was covered in hot ash in a matter of moments, it was as if Pompeii was frozen in 70 AD. Visiting Pompeii was like stepping back into the time of the Caesars.

Truth be told, Patty was happy things were back to “normal.” It was pleasant to have their working schedule and to go home to their apartment at night. A couple nights a week, and most Saturdays and Sundays, she and Rob played golf. He had improved somewhat and she was a little annoyed that so far this year he had beaten her more than half of the time … and yes, he was rubbing it in.

As Patty approached the cafeteria she heard a friendly but heated discussion.

“No way can you evaluate an assembly company with just 10 questions,” Phil Anderson stated emphatically.

“I’m really convinced we can, I’ve thought it through a lot,” responded Rob.

“What’s the spirited debate about?” asked Patty as she sat down.

“Rob thinks you can evaluate an assembly company by asking a lead process engineer only 10 questions. Phil thinks he’s nuts,” responded Patty’s best friend Jan Curtis.

“I’ve thought about this quite a bit,” said Rob. “I’ve just finished reading Malcolm Gladwell’s ‘Blink.’”  “Gladwell claims that often the best judgments can be made quickly with just a sampling of data.”

“Be specific,” challenged Phil.

“OK, I actually developed 10 proposed questions to evaluate a assembler. Let me list them and then defend them. Maybe you guys have better ones,” said Rob.

Patty thought, as she heard this, that it was good news that ACME was looking to buy more assembly companies to handle their ever-increasing workload, unlike AJAX, which was laying folks off.

Rob had come prepared; he actually had some printouts. His 10 questions were:

1. What is the composition of SAC 305?

2. What are tin whiskers?

3. In a stencil aperture, what is the area ratio?

4. What is an approximate peak temperature for a reflow oven in lead-free assembly?

5. A board is inspected after wave soldering and one lead is not soldered to the board. The board is run through the wave solder machine again and has the same defect on the same lead. What is the most likely cause of the defect?

a. The solder temperature is too low.

b. The pad on the board is oxidized.

c. The preheat temperature is too high.

6. What are local fiducials on a PWB for?

7. What does thixotropic mean in regard to solder pastes?

8. A chipshooter places passives at a rate of 36,000 per hour. It is placing 300 passives on a PWB. How many seconds will the chipshooter take to place the passives on one board?

9. A reflow oven belt speed is 100 cm/min. The PWB is 40 cm long. What is the minimum cycle time that the oven can support?

10. What is tombstoning?

“You have got to be kidding,” shouted Phil. “Everyone will score 100% on that test.”

Jan chimed in, “I’m not so sure. We hang around people all day who study this stuff. I’m not sure the typical process ‘engineers’ have enough time to study and learn new things. Remember the ‘water in the solder’ and the ‘isopropyl in solder paste’ incidents?”

At this comment, Phil spit up his ice tea and started choking from laughter. One of their friends, Sally Herman, had been sent to a recently acquired company to help with assembly process issues. One of the “process engineers” introduced himself by bragging that he was saving the company money by taking used, dried solder paste and mixing it with isopropyl alcohol so that the paste could be used again. Later in the day, the same chap shared that he thought he had a solution to the poor hole fill problem in lead-free wave soldering: the solder was too thick, and if it was mixed with water it would fill the holes better, he opined.

Jan added, “As a minimum, these questions act as a good screening process.”

Rob interjected, “That’s my point. I’m not saying this tells us everything, but you will agree that if a lead process engineer can’t handle these questions, it is unlikely he or she would be able to solve graping, or the head-in-pillow defect, right?”

All at the table murmured agreement.

“On second thought, maybe you have something here Rob,” Phil said. “What do you propose as a passing score?”

“Seventy percent,” Rob answered.

Are Rob’s questions reasonable to evaluate an electronics assembler? What are the answers? Comment with your answers. Stay tuned to find out.

Cheers,

Dr. Ron