Let’s check in on Andy Connors and Sue March at Castellanos Electronics after Maggie and John’s decision to buy the company. In our last episode, Sue was working on solutions to minimize solder defects that have been categorized in a Pareto Chart1, whereas Andy was working on creating a training program to develop some process engineers and implementing an improvement plan developed by Chuck Tower and José Castellanos.
After working so hard to bring Castellanos Electronics up to speed, Sue and Andy decided to go out to dinner by themselves for a change. They had often gone with José or some of the workers but thought they needed some time just for the two of them.
“Let’s go see the new Tom Hanks movie, A Man Called Otto, after dinner,” Sue enthusiastically suggested. “It’s a cute romantic comedy.”.
“Since it’s a romantic comedy, will you let me hold your hand?” Andy teased.
“Yes to the hand holding, but no necking,” Sue teased back, and they both laughed.
“You know the movie probably has that subtitle thing going on again,” Andy grumbled.
“We’ll survive,” Sue joked and punched his arm playfully.
Current movies from the U.S. were often played in English with Spanish subtitles at the theatre near the factory. Whenever they went to see a film, Andy and Sue would both get distracted reading the Spanish and then, if the translations were off, would let out a sigh.
At dinner, they discussed how the work was going at Castellanos Electronics, as they had only a little over a week to wrap things up.
“With José and some of his team, we have implemented the process improvement opportunities that Chuck and José identified. The new solder paste that has excellent response-to-pause has really helped improve productivity,” Andy began.
Sue asked, before taking a bite of her meal, “You were also working on line balancing, right?”
“Yes, surprisingly, their uptime wasn’t too bad, but the lines were almost never time balanced for the component placement machines,” Andy replied. “By time balancing the placement machines, production improved 8%. There was one case where the chip shooter was taking 55 seconds and the flexible placer only 26 seconds, meaning cycle time was 55 seconds. By moving some components off the chip shooter to the flexible placer, each machine needed only 47 seconds—a time savings of about 15%.” He then shifted the conversation to ask Sue about her progress. “How’s it going on the Pareto chart?” (Figure 1).
“We’ve made significant progress on graping, head-in-pillow (HIP), voiding, and insufficients, and we have only tombstoning left to work on. In all cases so far, we have reduced defects by 90% or more,” Sue said excitedly.
“So, what is your plan for tombstoning? I’m interested, since I don’t know much about it,” Andy said.
“Tombstoning occurs in the reflow oven when one side of a passive solder paste deposit melts before the other side and the surface tension of the melted solder pulls the passive upright like a tombstone,” she said. (Figure 2)
“So, we either have to prevent the one side from melting too rapidly or reduce the surface tension forces?” Andy asked.
“Good start, Einstein!” Sue said, laughing. “It helps to have a solder alloy that has a ‘pasty range,’ meaning that it doesn’t completely melt at one temperature. Since we use SAC305, which has a reasonable pasty range, we can’t improve too much in that regard.”
She continued, “Beyond the pasty range, we can try ensuring that the solder paste deposits are the same amount on each side of the passive and that the components are placed squarely with no skewing. I’m going to ask Miguel to check those things out first.”
“So, if addressing those things doesn’t solve tombstoning, we’ll have to reduce the surface tension forces some other way?” Andy asked.
“Yes, we could modify the reflow profile so that the melting is slower, but that might negatively affect graping,” Sue said. “However, we should look into it.”
After thinking a while, she continued, “Modifying the stencil would help a lot, but that would be an added expense and we should only do that if all else fails.” She then showed him an image of a proposed stencil (Figure 3).
“It’s quite easy to see how the stencil would work,” Andy said, excitement building in his voice. “There is almost no paste on the edges of the passive, so there is almost no paste to cause the tombstoning effect.”
They chatted for a few more minutes about Sue’s efforts, then she questioned, “How is the training going on your end?”
“We’re just about finished,” he replied with confidence. “I’ve covered all the material in the Handbook of Electronic Assembly2. I think they are well-prepared for the SMTA Certified Process Engineer’s exam3. As a matter of fact, I just gave them three practice quiz questions and they teased me that they were too easy.”
“What were the questions?” Sue asked.
He then shared these three questions:
“If they think those questions are easy, that’s really promising,” Sue said of the staff members in training. “I think many people would find them challenging.”
Epilogue
Sue and Andy finished all their assignments at Castellanos Electronics. All the workers who took the SMTA Process Engineer Certification exam passed with flying colors. Defects were reduced by 90% overall. The best news was that the team of workers now had the skills to run the factory when José wasn’t there and could also handle new yield, productivity, and quality issues on their own. Since he could now take an occasional vacation, José agreed to stay on as the factory manager, reporting to Maggie and John.
Tune in to the next episode to find out the solutions to Andy’s three problems.
References
Download The Printed Circuit Assembler’s Guide to… Solder Defects by Christopher Nash and Dr. Ronald C. Lasky. You can also view other titles in our full I-007eBooks library.
This column originally appeared in the March 2023 issue of SMT007 Magazine.
03-15-2023
Let’s check in on Andy Connors and Sue March at Castellanos Electronics after Maggie and John’s decision to buy the company. In our last episode, Sue was working on solutions to minimize solder defects that have been categorized in a Pareto Chart, whereas Andy was working on creating a training program to develop some process engineers and implementing an improvement plan developed by Chuck Tower and José Castellanos.
View Story02-22-2023
In this latest installment of Maggie Benson's Journey, Sue, Andy, and Chuck summarize their findings and identify an action plan to continue making progress on their goal to bring Castellanos Electronics up to standard. Chuck entrusts his development plan to Andy, while Sue again joins forces with Carlos and Miguel to keep chewing through the long list of manufacturing process defects that need resolving. Tune in next time to find out what Andy has decided to include in his SMTA Certification training program, as well as whether Sue's suggestions successfully lead to a decrease in HIP.
View Story02-01-2023
This month in the ongoing saga of Maggie Benson's Journey, Sue March and Andy Connors choose to remain in Mexico after the purchase of Castellanos Electronics to help Chuck Tower coordinate the company's transition. Using their previously drafted improvement plans, the group splits up to address the efficiency and defect-related issues they'd identified during their earlier tours of the factory. Sue teams up with Carlos to propose a solution to the company's biggest quality issue—solder joint graping—while Andy meets with the four promising candidates recommended to the process engineer training program
View Story11-30-2022
Editor’s note: Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this month's column, Andy and Sue prepare to take two journeys—one to Mexico to tour a facility that Maggie is interested in buying, and one of a more personal nature that will mean a more permanent union between them both. It's an exciting time in the lives of these two young professionals.
View Story10-18-2022
Editor’s note: Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this installment, Maggie's employees Andy and Sue finish teaching their pre-calculus class, then get "called into" Maggie's office where Professor Patty Coleman and others are waiting. What they learn truly comes as a shock and something they never expected.
View Story10-05-2022
Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this episode, Maggie's employees Andy and Sue continue to quiz one another as they prep to teach the company's SMT 101 workshop. Their discussions include some of the basic math and assembly concepts that are needed in today's shops.
View Story08-30-2022
Indium Corporation's Ron Lasky continues this series columns about Maggie Benson, a fictional character, to demonstrate the continuous improvement in SMT assembly. In this installment, Maggie and her fiance John note the positive changes at Ivy-Benson Electronics and attribute the change to two employees who really stepped up to the challenge of learning.
View Story07-27-2022
Editor’s note: Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this column, Ivy Benson employees Andy and Sue continue to quiz one on another on algebraic equations that they need to know in PCB assembly. While Andy feels outwitted by Sue, his own knowledge is improving. Will they make a good team?
View Story06-27-2022
Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this column, Ivy Benson employees Andy and Sue continue to test each other on the basics of surface mount technology as they prepare for certification. Lasky points out there are no sources of material to help a technician or engineer new to electronic assembly to learn the basics.
View Story06-01-2022
Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this month's column, two of Ivy Benson's young employees respond to Maggie's challenge to improve their assembly knowledge and skills. Does it have the desired effect?
View Story04-27-2022
Editor’s note: Indium Corporation’s Dr. Ronald C. Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this episode, Maggie and John meet with her grandfather, who sold the company to Maggie, to talk about how it's going.
View Story03-16-2022
Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. In this installment, the new owners have improved the facility and improved morale, but previous owner Ned Price isn't sold on the changes, and has a lot to say about it.
View Story03-02-2022
Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. The last column concluded with these questions: Will BE buy Ivy Electronics? What will the price be? What is in the action plan? What is 5S and the 8 Mudas?
View Story12-15-2021
In this fictional account of Maggie Benson, Indium Corporation's Ronald C. Lasky explores continuous improvement themes. This month, after reviewing the company's success with improving uptime, he introduces the idea of a Pareto chart which shows the yield fallout by failure mode types.
View Story11-24-2021
Editor’s note: Indium Corporation’s Ron Lasky continues this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly. Maggie was working in her office, deep in concentration, when she was startled by the phone ringing. It was her mentor, Professor Patty Coleman from Ivy University. Maggie reached to answer the phone. “Hi Prof…,” Maggie started, “Patty.” “Well, Maggie, we still need a little work on you calling me Patty,” Patty said, chuckling. “I am calling to thank you again for taking my family to Mount Ascutney to view the Milky Way. Rob, our boys, and I really enjoyed it. I didn’t consider that the new moon might be the best time for viewing. It was also neat to see Venus. I was unaware that Venus is in the Western sky after sundown because it is closer to the sun than the earth.”
View Story10-27-2021
Ronald Lasky continues his series on continuous improvement through this series with fictional character Maggie Benson. Here, he explains that with increased productivity, each unit produced is cheaper to make and you have more of them, so profits increase exponentially.
View Story09-15-2021
As the story continues, Maggie meets with Professor Patty Coleman, and finds something new to chat about. Back at Benson Electronics, the team is meeting about uptime on the line. What's new there?
View Story08-11-2021
In this fictional account meant to discuss continuous improvement methods, character Maggie Benson reviews the urgency of improving uptime on the lines with one of her employees.
View Story07-12-2021
In this fictional account, Maggie Benson's time on the golf course with her professor leads to important improvements at the factory.
View Story06-03-2021
In Part 2 of Dr. Ronald Lasky's fictional account of Maggie Benson, Benson Electronics learns of the change in ownership, while Maggie and John evaluate making some changes.
View Story05-05-2021
Indium Corporation’s Ronald C. Lasky has launched this series of columns about Maggie Benson, a fictional character, to demonstrate continuous improvement and education in SMT assembly.)
View Story
