Short answer: A device scales from prototype to mass production when eight things are true at the first prototype: the BOM uses standard parts with two approved sources; SMT is one-sided where the layout allows and THT is minimised; every net has a test point or an accessible pad; the board outline, fiducials and keep-outs suit an SMT panel; firmware is programmed and provisioned on the line through a defined interface; calibration is automated and stored on the device; the enclosure and connectors have assembly tolerances, not lab tolerances; and the design is under revision control with an engineering change process. Comtec Labs applies these rules in every design and every DFM review, because the same lines build the prototype and the series.
The eight rules
| Rule | Why it matters at volume | What it costs at prototype |
|---|---|---|
| 1. Standard parts, two sources | Allocation and EOL cannot stop production | A day of BOM work |
| 2. One-sided SMT, minimal THT | Halves assembly time and removes manual steps | Some layout effort |
| 3. Test point on every net | Flying probe now, ICT fixture later, without a re-spin | 1–2 % board area |
| 4. Panel-friendly outline and fiducials | Full panel utilisation, automatic placement, clean depanelling | Nothing if done before layout |
| 5. Line programming and provisioning | Firmware, keys and serial numbers loaded in seconds per unit | A defined programming interface |
| 6. Automated calibration | No technician per unit; results stored per serial number | Calibration routine in firmware |
| 7. Assembly tolerances | Boards drop into enclosures; connectors mate without force | Mechanical review with the enclosure supplier |
| 8. Revision control and ECO | Changes are traceable; production never builds an undefined state | A repository and a change form |
What ‘the same lines for prototype and series’ enables
When the first prototype is built on production SMT lines with the production stencil and reflow profile, the prototype run is the process qualification. The series launch then needs no re-industrialisation: the programme, the test fixture concept and the panel are already proven. In our experience this is worth one full prototype iteration and several weeks on a typical industrial product.
Signs a design will not scale
- Hand-soldered wires, bodge components or manual trimming on the prototype.
- Calibration by a person with a screwdriver.
- Firmware loaded through a debugger by an engineer.
- Components chosen from a hobby distributor's stock.
- No test specification, or a test that takes minutes per unit.
- An enclosure that needs filing to fit.
Key facts
- Test points cost 1–2 % of board area and save a re-spin when the ICT fixture is built.
- Line programming and provisioning typically takes seconds per unit; debugger programming takes minutes and an engineer.
- One-sided SMT roughly halves assembly time compared with a double-sided board with THT.
- Comtec Labs builds prototypes and series on the same SMT lines in Vaasa, Finland.
How Comtec Labs helps
Every design we do and every DFM review we run scores the design against these rules and reports what to change before the first board. Send your files or your concept and you get the list with the quote.
Frequently asked questions
Is it worth designing for scale if we only need 200 units?
Yes. Most of the rules cost nothing at design time and reduce the unit price and the risk immediately; they also keep the option of growth open.
When should DFM start?
Before layout. Component and outline decisions are cheap to change on a schematic and expensive on a routed board.
Can an existing prototype be made scalable?
Usually with one revision: replace risky parts, add test points and fiducials, define the programming interface and automate calibration.
Do you offer a design review for products built elsewhere?
Yes. A DFM and scalability review of your files is part of every quote.
Ready to reduce PCB surprises?
Comtec Labs offers a full suite of services to streamline your workflow:
PCB design service
PCB prototyping service
PCB component sourcing
PCB component assembly
PCB testing service
PCB repair and modifications
Printed circuit board production
PCB mass production