PCB milling is also known as isolation milling. This is a PCB manufacturing process of removing a section or sections of copper traces from a PCB. By scalping, the areas offer an excellent space to recreate signal traces, pads, and other structures, as shown in the layout file.
PCB milling process and PCB etch process aims at attaining the same results. However, both processes have advantages and disadvantages. For example, PCB milling does not rely on chemicals while PCB etch process uses chemicals. Nevertheless, both processes are subtractive.
Since PCB does not use any chemical, it is a perfect process for people without a lab environment. The etching chemicals produce harmful fumes and are corrosive when they react with copper traces.
Although PCB milling might be safer for many people, the quality of the board depends on various factors. Some of the factors that determine the quality include milling accuracy, the control, and the trueness of the system.
So, if the milling bits are not sharpened properly or the rotational speed is incorrectly set, the results will be unwelcome. On the other hand, if you etch the PCB, the quality will depend on the protective mask.
Advantage of PCB milling
PCB has become common to many people due to its numerous benefits. For example, the board does not fabricate with chemicals. Other advantages of PCB milling include:
*When using PCB milling, you do not need to handle chemicals. Keep in mind that etching chemicals produce harmful fumes.
*With PCB milling, you can create prototypes faster without thinking about the chemicals. It is even faster and more effective if the CNC machine can do both drilling and milling.
*Some boards may be difficult to handle through the wet process, while others may get damaged in the lab. Hence, the best process is PCB milling.
What is the PCB milling process?
The PCB milling process involves two systems, the software and hardware systems. Therefore, the interaction of the user and the hardware through the software allows for the circuit board’s formation.
*Software system – there are two software types: Raster and vector software. Both of them are supplied by the manufacturer.
*Hardware system – the hardware system is the numerically controlled milling machine. It may either have a serial or a port that connects to the main controller.
PCB milling processes you need to know
*PCB milling is a procedure of getting rid of redundant copper from a circuit board to produce paths and signals traces based on the layout design.
*In most cases, the milling process takes thirty minutes. However, some factors might affect the process. Some of these factors include the thickness of the bit, the dimension of the circuit board, and the components available, among others.
*The PCB manufacturer can provide you with the software for the milling.
*The milling sharpness and accuracy of the milling bits you use can have effects on the quality of the board.
*Even though PCB milling can be done in a lab environment, the process is non-chemical.
*Vector and Raster are the two main categorizations of the milling software.
*While Vector relies on data given by Raster, Raster comes with a less operating resolution.
When you need CNC machining in PCB fabrication
When you need CNC machining in PCB fabrication, learning more about the benefits and shortcomings is important.
From manufacturers to individuals, PCB milling is a process that comes with a few shortcomings. But if you can manage to perfect the art, you can manage to achieve the best results. Here are a few tips about CNC PCB milling to consider.
- Leveling – since PCB milling involves removing a thin metal layer, you need to have a consistent level. There is physical leveling and computer leveling.
- Track clearance – you need to pay attention to track clearance and make sure it is well adjusted.
- Coating – after milling, the copper can corrode if exposed. Hence, it would help if you protected it by applying a solder mask.
- Safety – as long you observe operation guidelines, everything will be okay with the PCB milling machine.
- Gcode files – if the CNC PCB can handle cutting, drilling, and milling, you need to ensure you have G-code files for all the operations.
Final word
PCB milling is considered an economical way of making a more robust and better board from the existing ones. You can get started with the above information since you know what PCB milling in PCB fabrication is. And since there are no chemicals involved, the process becomes the nicest of them all.
