Design Products That Delight Your Customers and Enable Your Manufacturing
By Dave Leone, Senior Director, Digital & Dimensional Engineering at GE Appliances, a Haier Company and James Morgan, PhD
Creating highly crafted products that delight customers comes from understanding critical product attributes and delivering them with precision. It is a fundamental part of Lean Product and Process Development (LPPD) and a good example of designing the value stream. And while this attention to detail is needed all along the value stream, it begins in design and engineering. One particularly important engineering discipline in this effort is dimensional control.
Dimensional control is one of the most important—and often least understood—disciplines in modern product development. Dimensional control was developed and refined over decades in industries such as automotive and aerospace, where high-volume production, and customer expectations for fit and finish demanded a far more rigorous approach to variation. It is a tangible and highly effective way to protect critical product attributes and bring product and process into alignment. Despite being foundational to how products come together, it is largely absent from engineering education. As a result, many engineers enter industry without ever learning how variation impacts assembly, fit, performance, and ultimately, customer perception.
Understanding the design problem
The consequences of this gap are everywhere and often accepted as normal. Products that technically meet specifications still fall short of meeting consumers' expectations. Doors don’t align quite right. Gaps are inconsistent. Assemblies require force. What should feel precise instead feels sloppy. Consequently, organizations absorb the cost—through scrap, rework, warranty, and frustrated customers who don’t come back.
This is often treated as a manufacturing problem, but really, it’s about design.
Your customers experience quality through what they can see, feel, and hear. They notice how a door closes, how a control feels, and how surfaces align. And in those moments, they make a judgment, not just about what they see, but about everything they cannot see. They assume the unseen is built with the same level of care as what is in front of them. Dimensional control is the discipline that ensures that assumption is correct. It shifts the mindset from designing to nominal geometry to designing for variation. It recognizes that every part and every process introduces variation, and that the role of dimensional engineering is to eliminate it where possible, and to control how it manifests in the final product.
Why is dimensional control is critical
Dimensional control requires a fundamentally different approach to design. Instead of relying on tolerances and adjustment, teams define how parts locate to each other. They coordinate datum structures across systems. They design assembly paths intentionally. They remove unnecessary design float. And they ensure that when parts come together, they do so predictably and consistently—without force, without correction, and without dependence on operator skill.
Program team is reviewing 3D tolerance analysis of a new design.
When this is done well, the difference is immediate. In early prototype builds, engineers begin to say things like, “This is the best build I’ve ever been a part of.” For some, it’s the first time they have assembled a product without having to force parts into position. Operators notice it even faster.
On recent programs at GE Appliances where the product and process were designed with fully integrated locator strategies, manufacturing teams quickly recognized the shift. Comments like, “These parts just fall together,” and “This is the easiest assembly I’ve ever built,” became common as assemblies came together with far less effort and variation. Plant leaders, often with decades of experience, saw it just as clearly. On a program where locator pins, holes, and slots were meticulously designed across the case, doors, and hinge systems, one plant manager noted, “This is the best door alignment I’ve ever seen on that platform.” The improvement was visible on the line and confirmed through 3D scanning showing tighter alignment and more consistent geometry across builds.
These are signals of a system that is working the way it was designed.
Millions saved
The impact is measurable. As the company invests $6.5 billion in new U.S. manufacturing, the launches of new products are happening faster because parts are fitting together better, quality is more predictable, and ramp up schedules are easier to achieve, which means millions of dollars saved. New platforms where fit, feel and finish have been optimized have saved several million dollars in warranty reductions compared to the platforms they replace. These outcomes are the result of designing for dimensional control from the beginning, not tighter tolerances or better inspection.
In recent years, digital tools such as 3D tolerance analysis, scanning, and virtual validation have made it easier to visualize and manage variation. These tools are powerful—but they are not the solution. Organizations often invest heavily in software and technology, results, only to be disappointed. You cannot “tool” your way into dimensional control. It is a discipline. A way of thinking. A way of designing.
Building this capability requires more than tools or training; it requires organizations to relearn how they design products and processes. Engineers must shift from focusing on individual parts to understanding systems. Senior engineers must rethink long-held assumptions. Teams must recognize that working harder will not improve quality if the underlying approach is flawed.
This is a belief system change, and like any meaningful transformation, it must be led through demonstration. It cannot be mandated. The most effective transformations are driven by leaders who are deeply technical, who can simplify complex ideas, and who are willing to work side-by-side with engineers to solve real problems. Leaders who build trust not through authority, but through competence, who show, rather than tell, what “good” looks like.
Engineers are reviewing 3D scan data.
Creating a craftsmanship culture
When engineers see assemblies come together cleanly, when they experience problems being solved at the design stage, when they realize what is truly possible, they begin to believe. And once they believe, they can’t ever go back.
Sustaining this capability in larger organizations requires a dedicated team that is focused on coaching and mentoring at all levels. A team that works part-by-part, interface-by-interface, helping engineers make better decisions and build deeper understanding. The goal is to design systems where variation produces consistent, high-quality outcomes… every time.
Quality engineer is refining a CMM inspection program.
Eventually, this approach becomes embedded in how your organization operates. Product quality improves. Launches become more stable. Assembly becomes more predictable. A culture of craftsmanship begins to take hold, and you create products your team is proud to put their name on. As teams begin to take pride in the products they create, your customers will notice.
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