Output Devices
Tools
MDX20
MILLING MACHINE
PCB Milling Workflow
The Roland MDX-20 is a desktop milling machine widely used in PCB production processes. In this case, it was integrated with Mods to generate cutting toolpaths from designs created in KiCad.
It is important to mention that before achieving consistent results, several challenges were encountered during the initial tests. These issues were mainly related to the generation of RML files. A high number of offsets produced files that were too large, causing the machine to stop processing at around 30% of the job. Additionally, the use of SVG files generated erratic or excessively complex toolpaths.
From these issues, it was understood that the efficient use, does not depend only on the design itself. This trial-and-error process helped to establish a more controlled and reliable workflow for PCB fabrication.
The electronic design of the board was using KiCad; ESP32C6, headers, resistors, LED, and communication lines such as SDA and SCL.
All components were placed and the traces were routed. The board outline was also defined at this stage, which is later used for the cutting process during fabrication.
The design was exported as SVG and prepared for fabrication using Inkscape and Mods. The traces were converted into a black-and-white image to generate the toolpaths . However, this stage introduced several challenges, because High DPI values and an excessive number of offsets generated files that were too large, causing the machine to stop processing at around 30% of the job.
These issues directly affected the milling results: insufficient cutting depth prevented the complete removal of copper, while incorrect tool configurations caused burrs or lifted traces. Through this process, it became clear that PCB fabrication depends not only on having a correct design but also on properly preparing and optimizing the files and machining parameters for the milling process.
The tools used for milling correspond to V-bit cutters, as they allow for fine detail and enable working with small trace separations. However, their performance strongly depends on the cutting depth, since even small variations directly affect the width of the machined traces.
The workflow involved establishing communication between Mods and the Roland MDX-20 using a local server to run Mods, while simultaneously executing a Python serial server (serialserver.py) that acts as an interface between the system and the machine.
The serial server was configured using the address 127.0.0.1 and port 1234. Once the connection was properly established, the terminal displayed multiple “connection accepted” messages, indicating that communication between Mods and the serial server was successfully achieved.
During the initial tests was not always stable or correctly configured, which made it difficult to reliably send data to the machine.
The components used in this PCB are surface-mount devices (SMD); Resistors, LEDs, and pin headers. Small size makes them sensitive to alignment and heat control.
This stage marked the transition from a passive circuit to a functional system.
In this case, a solenoid was controlled through the PCB as part of the system developed. This test represents the transition from basic validation to a fully functional application, integrating the different elements of the developed system.