Conformal coating service in Finland: automated selective coating for PCBs
Selective, UV-cured coating that protects your boards from moisture, dust and corrosion, from one prototype to series.
In short: Comtec Labs applies conformal coating to printed circuit board assemblies in Vaasa, Finland, on a fully automated selective coating line. We use HumiSeal UV50LV, a UV-curable coating that cures in seconds. The coating programme defines exactly which areas are coated and which stay clear, such as connectors and test points, so the thickness is consistent board to board. The service covers prototypes and series, including boards assembled elsewhere.
Who this service is for
Conformal coating pays off when a board will live with condensation, salt air, dust, chemicals or vibration. Typical customers are:
- industrial and automation companies with controllers and sensors in factory halls, outdoor cabinets or washdown areas
- marine and energy companies whose boards face salt, humidity and temperature swings on vessels, at substations or in wind and solar installations
- medical and defence electronics manufacturers who need long service life and a repeatable, documented process
- product companies whose boards are assembled by another supplier but need coating close to the end customer in the Nordic region
How a coating order runs
- Drawing and requirements. Send the assembly drawing with the areas that must stay uncoated, the operating environment and, if you have one, your coating specification. Quantities and whether the boards are assembled by us or elsewhere complete the request.
- DFM review and coating programme. Keep-out zones and parts that could trap coating are checked in the DFM review, and we propose the coating programme together with the quote.
- Design review. Coating type and masking are agreed with you in the design review before the first board is coated, so the result matches your drawing.
- Incoming inspection for external boards. Boards assembled elsewhere go through an incoming inspection before coating.
- Selective coating and UV cure. The automated line applies HumiSeal UV50LV only where the programme says, and UV light cures the film in seconds.
- Delivery or next step. Coated boards are packed and delivered with a certificate of conformance, or passed on to box-build when we build the whole device.
The coverage of every coated board is inspected under UV light.
Coating capabilities
| Area | What we offer |
|---|---|
| Process | Fully automated selective conformal coating line |
| Coating material | HumiSeal UV50LV, UV-curable |
| Curing | UV cure in seconds, in line |
| Uncoated areas | Connectors, test points and other defined areas kept clear by the programme |
| Quantities | Prototypes and series on the same line |
| Boards from other suppliers | Stand-alone coating after incoming inspection |
For context, the industry uses four main coating families. Acrylic (AR) is the easiest to apply and rework, urethane (UR) has the best chemical and abrasion resistance, silicone (SR) covers the widest temperature range, and UV-curable coatings cure in seconds and suit fully automated lines. Film thickness of 25–75 µm per IPC-CC-830 is typical for acrylic, urethane and silicone coatings.
Lead times
Because the coating is applied by programme and cured by UV in seconds, coating itself is rarely what sets the delivery date. When we also assemble the boards, coating runs as a step on the same production flow, so it does not add a separate shipment or a second supplier to manage. For a new product, the coating programme is proposed with the quote and agreed in the design review, so the first batch is ready to run when the boards are. For boards assembled elsewhere, the date depends on when the boards arrive and pass incoming inspection. We confirm the delivery date with each quote.
As part of an assembly order, coating adds 1 working day.
Coating line and production environment
Coating is done in an ESD-protected production environment in Vaasa, on a fully automated selective conformal coating line with in-line UV curing. The same building houses SMT and THT assembly, AOI, functional test and box-build, so a board can be assembled, tested, coated and built into its enclosure without leaving the factory. Selective application means the programme, not manual taping, decides where coating goes, which keeps the result repeatable.
See the full equipment list, capabilities and lead times
Quality and standards
- Coating areas and keep-out zones are fixed in the coating programme, so every board in a batch gets the same coverage.
- Boards we assemble are built to IPC-A-610 class 2 as standard or class 3 on request, with AOI on every board before coating.
- Boards from other suppliers pass an incoming inspection before they are coated.
- Every shipment carries a certificate of conformance, and serial traceability can be configured per product.
In the industry, coating quality is commonly checked under UV light, because most coating materials contain a UV tracer, together with thickness measurement and adhesion checks per IPC-CC-830.
When does a board need coating?
Coating is cheap insurance in a harsh environment and an unnecessary cost in a benign one. The table shows typical industry practice; the final decision is yours and is agreed in the design review.
| Environment | Typical practice |
|---|---|
| Marine, coastal, offshore | Coating required |
| Outdoor, unheated cabinets, agriculture | Coating required |
| Washdown, chemicals, oil mist | Coating required |
| High vibration with fine-pitch parts | Coating recommended |
| Dry, sealed indoor enclosure | Usually not needed |
In automated series production, coating typically adds around €0.50–€3 per board in the industry, far less than a manual spray-and-mask process. Your actual price is given in the quote.
Frequently asked questions
Which coating material do you use?
We use HumiSeal UV50LV, a UV-curable conformal coating applied on a fully automated selective line. It cures in seconds under UV light, which keeps the process fast and the thickness consistent.
Can connectors and test points be left uncoated?
Yes. The coating programme defines which areas are coated and which stay clear. Mark the keep-out zones on the assembly drawing; we check them in the DFM review and agree the masking with you in the design review.
Do you coat boards that were assembled by another manufacturer?
Yes. Coating is offered as a stand-alone service for boards assembled elsewhere, after an incoming inspection of the boards.
Does conformal coating make a board waterproof?
No. Coating protects against condensation, humidity, dust and contamination. Immersion or pressure washing needs a sealed enclosure or potting in addition.
Is coating available for prototypes as well as series?
Yes. Prototypes and series run on the same automated line with the same programme, so a prototype is coated the way the series will be.
Related reading
- When Does a PCB Need Conformal Coating? A Decision Guide
- High-Reliability Marine Electronics PCB Assembly in Finland
- Reliable PCB Manufacturing for Energy Systems in Finland
- IPC-A-610 Class 2 vs Class 3: Which Should You Specify for Your PCB Assembly?
Related services
- PCB assembly
- PCB functional testing
- PCB series and low-volume production
- PCB prototype assembly
- PCB repair and rework
Request a quote for conformal coating
Send the assembly drawing with keep-out zones, the operating environment and quantities. You get a price, our DFM findings and a proposed coating programme.
