Viwinco was winning. It shipped hundreds of made-to-order windows a day, most on a one-week promise, with no finished-goods inventory. From the outside it looked lean. Inside, it ran on overtime, large batches, and firefighting, and the leadership team knew that way of working would not scale. This case study is the honest, four-year account of what they changed, what it cost, and what it produced.
“It's not perfect. It's just this continual thing, and you have to have conviction that, directionally, it's the right approach.”
— Mike Duncan, President and CEO, Viwinco
What you will learn
Viwinco did not set out to follow a framework. Looking back, its actions answer the five questions every lean transformation has to address:
What problem are we solving? Why a fast, profitable, growing business still needed to change.
What is the work? How they moved a 100 percent custom line to one-piece flow, and cut work-in-process from more than 40 units to about one.
What capabilities are required? How they built a frontline team-leader role that did not exist before.
What management system is required? How a 15-page strategy document became hoshin kanri and the Viwinco Performance System.
What basic thinking is required? The mindset, fix the process not the people, that made all of it hold.
Inside the case study
The full Viwinco Performance Improvement table: on-time-in-full delivery, quality, safety, work-in-process, and revenue, before and after.
The model-line redesign, the equipment behind one-piece flow, and the new glass plant that cut seal failures by 90 percent.
How AI became a “Third Coach” on a materials-science problem standardized work could not reach.
The Keys to Success summary that maps the whole transformation to the five framework questions on one page.
Who it is for
Operations and continuous-improvement leaders, plant and site managers, and executives who want a concrete, practitioner-level account of an enterprise lean transformation, not a theory piece.
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