Executive Summary & Key Takeaways
- Unresolved design geometry causes most cost overruns. High BOM lines exist because of tolerance stack-ups and secondary machining operations that were not designed out of the product.
- Negotiating unit prices cannot fix poor engineering. True cost optimization requires physical tear-downs to simplify component shapes and combine parts into single molded geometries.
- Relaxing assembly tolerances reduces manufacturing complexity. Conceiving parts with built-in alignment features eliminates secondary manual calibration on the line, lowering overall labor costs.
The BOM doesn’t lie. The designer does. Every BOM overrun I’ve seen in 15 years starts the same way: cost review meeting, spreadsheet on screen, someone pointing at line items, and a conversation centered on suppliers, quantities, and margins. Nobody looks at the geometry. A Bill of Materials is not a financial document; it is a map of every design decision that was never fully resolved. The expensive component is there because a shape required it. The redundant bracket exists because a tolerance stack-up wasn’t designed out. The secondary operation survives because the form was conceived without asking how it would be held on the production line.
Why Negotiation Cannot Fix Poor Design
I’ve watched teams renegotiate with four different suppliers on a single component, recovering €0.08 per piece. The real saving was in the component itself, which didn’t need to exist. The correct entry point for cost reduction is not the spreadsheet; it is the physical product, disassembled on a table, with someone who knows what to look for. In contract and manufacturing discussions featured on Dezeen, engineering simplification is consistently highlighted as the most effective route to long-term profitability. Every line in your BOM is a decision. The question is whether it was a conscious one.
Steps to Execute Physical Value Engineering
To reduce manufacturing costs without sacrificing quality, design teams should follow a physical tear-down process:
- Component Consolidation: Merging multiple parts into single molded or cast geometries.
- Tolerance Relaxation: Redesigning joints so they do not require tight, expensive machining tolerances.
- Process Optimization: Shaping parts to avoid secondary sanding, painting, or machining operations.
The World Design Organization (WDO) supports these efficiency practices as they minimize raw material consumption and reduce assembly energy, aligning engineering constraints with industrial sustainability.
Interested in optimizing your product margins? Read our guide on industrial design as an economic lever or learn more about our CMF strategy.