Case Study
CNC Machining Case Study: How We Reduced Production Costs by 40% for a Medical Device Startup
A real-world story of how strategic DFM optimization, process selection, and supplier collaboration transformed a startup’s manufacturing economics.
The Challenge: High Costs Threatening Product Viability
In early 2025, a medical device startup approached us with a problem. They had developed an innovative handheld diagnostic device and were preparing for their first production run. The enclosure and internal mounting brackets — 7 unique aluminum parts — were being quoted at $84.50 per set by their existing supplier. At their target volume of 500 units initially (scaling to 2,000), the math didn’t work:
7 parts × $84.50/set × 500 sets = $42,250 for the first production run
Target cost per set for commercial viability: ≤$52.00
Gap to close: $32.50 per set (38%)
Step 1: DFM Review — Finding the Low-Hanging Fruit
Our engineering team performed a thorough Design for Manufacturing review of all 7 parts. Within 48 hours, we identified several opportunities:
| Part | Issue Found | Recommendation | Impact |
|---|---|---|---|
| Housing (Main) | Deep pocket requiring 5-axis + long tool reach | Split into 2 parts with fasteners; 3-axis machining | -$12.80/unit |
| Bracket A | ±0.005mm tolerance on non-functional surface | Relax to ±0.05mm standard tolerance | -$4.20/unit |
| Mount Plate | Specified 7075 aluminum (overkill) | 6061-T6 with Type III hard anodizing | -$3.50/unit |
| Connector Ring | 3 separate CNC operations | Redesign for single-setup machining | -$5.60/unit |
| Cover Plate | Complex internal radii requiring custom tooling | Use standard radius; no functional impact | -$2.80/unit |
| TOTAL DFM Savings | -$28.90 per set | ||
Step 2: Process Optimization — Working Smarter
Beyond design changes, we optimized the manufacturing workflow:
- ✦ Batch programming: We programmed all 7 parts to share common tooling, reducing tool change time by 60% across the production run.
- ✦ Fixture consolidation: Designed a custom fixture plate that held 3 different parts simultaneously, cutting setup count from 7 to 3.
- ✦ In-process inspection: Integrating CMM checks during production rather than post-production eliminated rework batching delays.
- ✦ Surface finishing bundling: All 7 parts went through Type III anodizing in a single batch, reducing finishing costs by 25%.
Step 3: The Results
| Metric | Before | After | Change |
|---|---|---|---|
| Cost per Set | $84.50 | $48.90 | ↓ 42.1% |
| Setup Operations | 7 | 3 | ↓ 57% |
| Lead Time | 8 weeks | 5 weeks | ↓ 37.5% |
| Quality Pass Rate | 97.2% | 99.6% | ↑ 2.4% |
| Total Run Cost (500 sets) | $42,250 | $24,450 | Saved $17,800 |
- Involve your manufacturer during the design phase — not after drawings are finalized
- Challenge every tight tolerance: “Is this dimension functional or just a habit?”
- Material selection has cascading cost effects on tooling, speed, and finishing
- Good DFM feedback is worth more than the lowest unit price
Want Us to Review Your Design for Cost Savings?
Send us your CAD files for a free DFM analysis. Our engineers will identify cost-saving opportunities — before you commit to production.
