Let me know if this story sounds familiar. “You have a contract manufacturer (CM) and you are not a 100% sure how your product is being built.”
You have build instructions, but the CM hasn’t “filled in the blanks” over the years. No documentation. No visibility. No real control.
Here’s what you can do to get control back and protect yourself from one day finding yourself unable to build your own product.
1. Document Reality First
Before you write new procedures, go see what your CM is doing. Interview the floor experts. Find the person who’s built 500 units with muscle memory. They have the knowledge you’re relying on—but it’s not on paper.
2. Build Instructions That Work Without Unicorns
If a competent tech can’t build a good unit using just your docs, you’ve got a problem. Don’t rely on tribal knowledge or the “magic touch” of your 10-year veteran.
3. Move Tests to the Point of Failure
Find where problems actually occur, and test there.
- Bad grounding? Add a continuity check right after that bolt goes in.
- Split-pair Ethernet issues? Use a $50 tester before it hits the assembly line.
Don’t wait until the end of the process to catch things that started at step 2.
4. Quality = Closed-Loop Thinking
Perfect reliability is a myth. Instead, set targets (e.g. <5% warranty returns in 2 months), and continuously improve based on field data. But watch out:
Dirty data is worse than no data.
If your root cause process isn’t consistent, your conclusions are garbage.
5. Yield ≠ Quality
If you’re shipping high-yield builds but seeing field failures, it’s your inspection process that’s broken.
Field Failures – Yield Loss = Inspection Weakness
Know that number. Track it. Improve it.
6. Build Independence
Here’s your North Star:
If your CM disappeared tomorrow, could you spin up another one using your documentation and processes?
If not, you’re not in control. You’re dependent.
Getting serious about quality isn’t about adding more tests—it’s about designing a process that doesn’t need magic to work.
I’d love to hear it. Let’s swap battle scars.
Here’s the deal:
If you share a story about working with a CM—win, fail, or total disaster—I’ll send you my PDF Field Guide to Improving Contract Manufacturer Quality Control.
No strings. Just good engineering karma.
adam@apexridge.com
-Adam