Laser Stencil - Laser Surface Mount Stencil

Laser stencil is a precise kind of stencil used in assembling components during PCB manufacturing and assembly. When it comes to manufacturing electronics and pieces of equipment, precision is essential. It is especially true when your product reaches global consumers; as such, you will need to ensure that they all work together.

This guide explores the uniqueness of Laser stencils in PCB manufacturing and assembly processes.

What is a Laser Stencil?

A laser stencil is a thin sheet of material, typically stainless steel, that has been precisely cut using a laser to create openings in the shape of the desired solder paste pattern. This stencil is placed over the PCB during the assembly process and serves as a guide for depositing the right amount of solder paste onto the board's pads. The use of laser stencils allows for greater accuracy, repeatability, and consistency in the solder paste application process, resulting in higher quality PCB assemblies.

Laser stencils are vital in PCB manufacturing because they enable PCB manufacturers to work efficiently and accurately. While the PCB industry is constantly introducing complex circuit designs, there is a need to approach stenciling differently.

Process of Laser stencils

Many PCB manufacturers employ laser stencils due to their speedy, accurate and precise process. As such, they employ laser stencils to manufacture large volumes of PCB units. The use of laser stencils is cost-effective and saves time. Here are the processes involving laser stencils:

• Machine set up
• Hole cutting
• Hole checking
• Deburring and polishing
• Framing
• Final quality control
• Packaging

These processes are automatic; a machine can blaze through these processes in minutes. Let’s briefly explain each of the processes. 

Machine set up

The setup process involves starting and warming up the laser machine. Also, this process requires cleaning and calibrating the machine settings so as not to ruin the processing of the stencils.

Hole cutting

After setup, the stencil is loaded into a drawer which moves into the laser machine’s cutting zone. The machine’s aperture then cuts a pattern in the printed circuit board.

Hole checking

After cutting, a laser beam scans the stencil to examine its cavity. In events of imperfection in the pattern, the stencil moves back into the machine.  

Deburring and polish

After automatic visual inspection, the laser machine employs a water jet to remove the burrs inside the stencil. After, the machine polishes the edges of the stencils using a buffing wheel to reduce scratches and defects in the product.

Framing process

After proper deburring and polishing, the laser machine cuts the stencil into the desired form. After, it is then moved to the framing area, where it stacks and groups the molded form in a particular order.

Final Quality Control

This process requires thoroughly inspecting the finished product for any post-production defects. This step is vital to double-check any unnoticeable imperfection during previous checks and inspections.

Product packing

The stencils are then moved into a cleanroom for storage and packaging. They are placed into an inert material box to prevent the metal stencil from rusting and ruining the product.

Final Thoughts on Laser Stencils

Looking back at the inception o PCB manufacturing, the evolution over the years has been incredible. New PCB technologies focus on reducing costs, increasing speed and improving quality in PCB fabrication, manufacturing, and assembly processes.

The use of laser stencils helped the PCB industry I adapting to automated processes that are efficient and offer low maintenance. Laser stencil’s accuracy has a significant impact on the PCB assembly quality.

It is then noteworthy that NextPCB highly recommends using laser stencil in the PCB assembly process. It is especially applicable in mass PCB production due to its high precision and efficiency. Also, laser stencils save time, making their machines effortless.
NextPCB is moving with the technological trend, with more PCBs and components becoming more compact and denser. That is why NextPCB is staying ahead of its competition in providing one-stop PCB solutions in PCBs. Their range of services from PCB prototype, assembly, and testing are automated, reliable and efficient. 
Consider this excellent PCB Manufacturer today and enjoy the quality and efficient laser stencil products.