# PCB Prototyping Process and Quote Guide
PCB prototyping is the critical validation step before a product moves into mass production. A clear prototyping workflow and transparent quoting logic help engineers avoid detours and shorten lead times. As a circuit board manufacturer with over 15 years of experience, Sunking PCB breaks down every step from file submission to sample delivery.
1. File Submission: Complete Files Move Faster
The first step is submitting production files. The more standardized your files, the faster quoting and production go. We recommend providing:
- Gerber files (RS-274X): layer artwork, solder mask, silkscreen, and drill data
- Drill file (Excellon): hole sizes, positions, and through/blind/buried hole notes
- Stackup and process notes: layer count, board thickness, copper weight, impedance requirements
- BOM and pick-and-place files: if you also need assembly (PCBA) prototyping
If you only have native design files (Altium, KiCad, etc.), you can submit them directly and our engineers will convert them, though this adds a little front-end time.
2. DFM Review: A Checkup Before Production
Once files arrive, our engineering team runs a DFM (Design for Manufacturability) analysis, the core step for ensuring sample yield. Common checks include:
- Whether minimum trace width/spacing meets process capability (Sunking supports 2mil/2mil)
- Whether the minimum hole size is machinable (Sunking minimum mechanical hole is 0.075mm)
- Solder mask bridges and legible silkscreen
- Impedance design matching the stackup
- Reasonable board outline, panelization, and process edges
Any issues found are reported back, and production only starts after the engineer confirms, avoiding samples that turn out unusable.
3. Quoting: Key Cost and Lead-Time Drivers
A prototype quote is driven by multiple technical parameters, not guesswork. The table below outlines the main factors and their impact:
| Factor | Impact on Price / Lead Time |
|---|---|
| Layer count | More layers mean more complex lamination and drilling, raising price and lead time (Sunking supports up to 60 layers) |
| Board size | Larger area means higher material cost; oversized boards need special equipment (Sunking max 1250Ă—570mm) |
| Quantity | Small prototype runs have high unit cost; higher volume spreads out engineering and setup costs |
| Material | Standard FR-4 is most economical; high-frequency, high-Tg, and metal-core materials cost significantly more |
| Copper weight | Standard 1oz is fastest; heavy copper (Sunking supports >12oz) extends etching and lamination time |
| Surface finish | HASL is cheapest; ENIG, immersion silver, etc. cost more but suit fine-pitch pads |
| Lead time | Rush prototyping requires insert scheduling and carries a surcharge |
Understanding this table lets engineers weigh cost during design, for example avoiding unnecessary high layer counts or heavy copper.
4. Sample Production: From Material to Finished Board
After the quote and DFM are approved, production begins. Core steps include:
- Cutting and inner-layer imaging: etch inner-layer traces and run AOI inspection
- Lamination: stack and bond multilayer boards under heat and pressure
- Drilling and plating: mechanical/laser drilling followed by copper deposition and plating
- Outer-layer imaging and solder mask: pattern plating, etching, and solder mask printing
- Surface finish and profiling: apply ENIG or other finishes as needed, then rout or V-cut
- Electrical test and final inspection: flying probe or test fixture for 100% electrical testing
Sunking's factory in Huizhou holds ISO9001, ISO14001, ISO13485, IATF16949, and UL certifications, so samples are quality-controlled to production standards.
5. Inspection and Shipping
Finished samples undergo sampling inspection for appearance, dimensions, and impedance, then are packed and shipped once they pass. Most standard prototypes can be delivered within a few business days, and rush orders can be compressed further. Shipments include a test report to support your incoming inspection.
Summary
Prototyping efficiency depends on how standardized your files are, how well DFM communication goes, and how well you understand the quote drivers. Think through variables like layer count, material, and surface finish in advance, and you can strike the right balance between cost, performance, and lead time.
If you are getting ready to prototype, send your Gerber files to the Sunking engineering team. We will run a free DFM analysis and give you a transparent quote to help you get quality samples quickly.