A stencil is a thin metal sheet used to apply solder paste onto a printed circuit board (PCB) during the surface mount assembly process. High quality stencils are crucial for accurately transferring solder paste deposits onto pads to produce reliable solder joints after reflow. This guide examines the top PCB stencil manufacturers across the globe and what criteria distinguishes the leading suppliers.
What is a Solder Paste Stencil?
A stencil is a thin plate made from stainless steel, nickel alloy, or brass. It contains laser cut apertures matching the pads on the PCB. During solder paste printing, the stencil is aligned over the board and a squeegee blade presses paste into the openings. As the stencil lifts away, precise volumes of solder paste are deposited in the required locations.
A laser cut solder paste stencil aligned over a PCB
High quality stencils are essential for:
- Accurate solder paste release without bridging
- Consistent deposit volumes and locations
- Clean aperture walls without burrs
- Stencil longevity over many print cycles
- Handling fine pitch components down to 0.3mm
We will now examine the top PCB stencil manufacturers worldwide capable of supplying stencils that meet these demanding requirements.
The 6 most common verities of stencils by size and type is mentioned below.
- PCB Prototype Stencil
Size: 10” x 12” max
Type: Squeegee
Add on: Board holder
Size: Over 10” x 12”
Type: Squeegee
Add on: Board holder
- Kit-Leaded Prototype Stencil (SMT)
Size: 10” x 12” max
Type: Solder leaded paste
Add on: alcohol wipes x 2, gloves x 1 pair, temperature marker
- Kit-Leaded Prototype Stencil Oversized (SMT)
Size: Over 10” x 12”
Type: Solder leaded paste
Add on: alcohol wipes x 2, gloves x 1 pair, temperature marker
- Prototype Kit-Lead Free Stencil (SMT)
Size: 10” x 12” max
Type: Solder lead-free paste
Add on: alcohol wipes x 2, gloves x 1 pair, temperature marker, grab and place tool,
- Prototype Kit-Lead Free Stencil Oversized (SMT)
Size: Over 10” x 12”
Type: Solder lead-free paste
Add on: alcohol wipes x 2, gloves x 1 pair, temperature marker, grab and place tool.
1. Rayming Technology
Established in 1992, Rayming is headquartered in Chongqing, China with facilities across Asia, Europe, and the Americas. They are among the world leaders in high accuracy stencil printing equipment and also manufacture compatible stencils. They work with over 1000 clients globally across the automotive, IoT, medical, and other industries.
Their stencils feature:
- Etching tolerance down to +/-12.5 μm
- Thickness tolerance +/-2 μm
- Proprietary laser cutting for minimal roughness
- Aperture positional accuracy of 10 μm
- Nickel alloy and stainless options
Rayming stencils are optimized for use in their advanced solder paste printers to achieve high first pass yields. But the stencils can also be used on standard printing platforms.
2. Guglielmo Trifiletti PCB Technologies Co
Italian company GPT specializes in ultra-fine line PCB production and matching stencils capable of handling advanced HDI boards. Their laser cutting and electroforming technologies produce stencils with tolerances rivaling photochemical etching.
Key capabilities include:
- 5 μm line/space etching capability
- Laser cut apertures down to 0.15mm
- Electroformed nickel stencils with 3 μm tolerance
- Stainless and nickel alloys available
- Clean room assembly and packaging
Their stencils are used by European manufacturers of smartphones, IoT devices, automotive electronics and other densely populated PCBs that demand precise solder paste printing.
3. MicroCraft Technologies
Singapore based MicroCraft produces laser cut stencils along with precision etching and CNC milling services. They focus on high-mix, low-volume orders.
Their stencils feature:
- Quick turnaround in 1-2 days
- Laser cut apertures from 0.1mm
- Etching down to 0.05mm lines/spaces
- Brass, stainless and nickel alloys
- Frame and jig customization
MicroCraft services IoT, consumer, aerospace, and industrial companies needing fast stencil prototypes and pilot builds with high fidelity to the PCB design data.
4. Shenzhen Mekin PCB Equipment
China’s Mekin Technology provides advanced solder paste printers and SMT assembly equipment. They also leverage their expertise in precision mechatronics to produce high accuracy stencils matched to their printers.
Mekin stencils offer:
- Laser etching tolerance down to +/- 5μm
- Nickel alloy composite and stainless steel
- Micro-etched walls for consistent paste release
- Aperture positional accuracy of <±0.002mm
- Cleanroom assembly and packaging
By pairing optimized stencils with their printing systems, Mekin enables ultra-fine pitch SMT assembly down below 0.4mm pitch.
5. Sunzing Electronic
Founded in 1998, Shenzhen Sunzing specialized in stencil manufacturing for the electronics assembly industry in China. They provide stencils for everything from consumer electronics and LEDs to automotive controls and aerospace avionics.
Sunzing stencils feature:
- Pure nickel or nickel alloy composite
- Laser cut tolerances down to ±25μm
- Fine pitch capability below 0.3mm
- Smooth aperture walls
- Quick turnaround
- Stencil cleaning services
Their high quality stencils support advanced electronics manufacturing across China’s thriving technology sector.
6. EDM Precision Industrial
Based in Shenzhen, EDM Precision is focused on CNC milling, laser cutting, and photo etching services. This includes manufacturing metal stencils for SMT assembly. They have particular expertise in quick-turn prototyping and pilot builds.
EDM stencils provide:
- 24 hour expedited turnaround
- Etched tolerances down to ±0.05mm
- CNC routing for thick stencils up to 0.25″
- Laser cutting accuarcy to 0.002mm
- Stainless steel and nickel alloy options
- Antistatic coatings
EDM services a wide range of customers needing fast stencil samples for new product introduction and ramp to production.
7. Jingshun Precision Engineering
Founded in 2004, Jingshun specializes in chemical etching and CNC machining. Located in Dongguan, China they produce metal stencils among other precision components for electronics and semiconductor equipment.
Their stencil capabilities include:
- Quick turn prototypes in 5 days
- Mass production tools
- Laser cut, photo etched and CNC milled stencils
- Stainless, nickel alloy and brass
- Tolerances down to ±0.003mm
- Frame mounting and cleaning services
Jingshun supports small batch manufacturing for China’s fast-paced electronics sector.
8. ASM Assembly Systems
ASM Assembly Systems produces advanced SMT pick-and-place, screen printers, and other assembly equipment. The company has locations worldwide. Their MicroStencil division provides optimized stencils for use in ASM printers.
Key MicroStencil features:
- Laser cut apertures down to 0.15mm
- Positional accuracy to 25μm
- Optimized frame geometry for ASM
- Nickel, stainless steel, and brass
- Cleanroom assembly and packaging
By matching ASM’s printers with stencils designed for them, optimal paste printing results are achieved.
9. Metal Etch Services
California based Metal Etch Services has been a stencil supplier to EMS companies since 1985. They offer in-house laser, chemical etching, and EDM manufacturing with rapid turnaround services.
Metal Etch stencils include:
- 24 hour rush production
- Tolerances down to ±0.001″
- Laser cut and etched apertures
- Stainless, high-temp steel, brass
- Frame designs for all printers
- Step stencil fabrication
Their combination of quick lead times and precision etching makes Metal Etch popular among US electronics manufacturers.
10. Electronic Stencil
Located in Johnson City, Tennessee, Electronic Stencil provides stencils to US and Canadian EMS providers along with stencil printers. They use chemical etching and laser cutting for fast production of prototype through high volume stencils.
Their stencils feature:
- Lead times as fast as 6 hours
- Dry etch and wet etch options
- Laser cut tolerance to 0.001″
- Stainless and nickel alloys
- Frame mounting and cleaning
- Stencil repair services
Electronic Stencil’s quick delivery makes them suitable for accelerated new product launches.
Selection Criteria for PCB Stencil Manufacturers
Here are key factors to consider when selecting a stencil supplier:
- Lead Times – Ability to deliver in hours, days or weeks
- Quality – Precision and repeatability of apertures and features
- Materials – Compatible alloys for PCB technology
- Facilities – Environment controls including cleanrooms
- Equipment – Laser, etching, CNC capabilities
- Volume Scalability – Prototypes through mass production
- Design Support – Assistance optimizing stencil designs
- Proximity – Local vs. offshore locations
- Pricing – Budgetary fit and value
- Reliability – Proven reputation and customer base
Work closely with your EMS partners and PCB assemblers to select proven stencil manufacturers that fit your product’s technical requirements, schedule, and budget needs.
Benefits of Using a Professional Stencil Supplier
Purchasing stencils from an established stencil manufacturer offers many advantages versus shop-floor in-house fabrication:
- Access to advanced laser and etching technologies
- Precision tolerances down to 5 μm or below
- High consistency across production stencils
- Equipment optimized specifically for stencils
- Cleanroom assembly and packaging
- Inventory of standard frames and foils
- Design expertise to optimize stencil geometries
- Quick turnaround of prototypes and early builds
- Capacity for stable supply through ramp up
While in-house stencil making can work for R&D, partnering with a professional supplier is recommended to achieve the accuracy and repeatability needed for smooth manufacturing ramp up and reduced defects.
FQA about PCB Stencils
What is the typical tolerance for a laser cut stencil aperture?
Laser systems can usually achieve tolerances down to around ±25 μm for location and size of apertures. High end lasers reach ±15 μm or better.
What is the minimum aperture size that can be laser cut in a stencil?
Lasers can cut apertures as small as 0.1 to 0.15 mm. Below this, chemical etching may be required.
How many times can a stencil be used before requiring replacement?
With proper handling, high quality stencils can often last for over 1000 cycles. Gradual stretching reduces accuracy necessitating replacement.
What thickness of stencil is typically used?
Common stencil thicknesses range from 0.1 mm to 0.15 mm. Thicker stencils around 0.25 mm may be used for higher deposit volumes or bridging prevention.
How flat must a stencil be for accurate printing?
Stencils require very tight flatness, usually below 0.0025 mm deviation per inch. Any warpage degrades printing consistency.
Conclusion
A precision solder paste stencil is crucial for high yield SMT production. Partnering with an established stencil manufacturer provides access to advanced laser and etching capabilities that far exceed shop-floor fabrication. When evaluating stencil suppliers look for proven expertise in your product’s materials and feature sizes along with competitive lead times and pricing. The leading manufacturers serve diverse electronics segments worldwide by consistently delivering stencils with tolerances and reliability measured in microns.
