DIY PCB Inspection Machine

With today’s high-quality custom PCB manufacturers, there’s a very good chance that what you design with EDA packages like KiCad will come back built to spec. What you do with it from there, however, is an open question. Did you really place all the tiny components in their correct positions and orientations? For that matter, was solder applied correctly everywhere?

To help address such concerns, Mr Innovative built a PCB inspection machine – which could potentially be used for other viewing purposes as well. It features a 50x to 1600x USB microscope, and a motorized stage on which PCBs are placed for viewing. The platform moves in the X and Y axes via a linear rail system, similar to a CNC machining setup, pulled along by 28BYJ-48 stepper motors and belts.

User interface for the inspection machine is via a small joystick, which interfaces with a custom Arduino Nano-based PCB. This PCB includes two A4988 stepper drivers that power the device's steppers. Actual magnified image viewing is accomplished via a smartphone, mounted to the aluminum extrusion assembly that also holds the microscope in place.

The build process is outlined in the video below, with some possible machinery damage and brief adult language around the 1:30 mark. Interestingly, while this machine should be helpful for future projects, it wasn't available to inspect the actual PCB that powers it. Such is the conundrum with this type of process improvement projects, but Mr Innovative still got things working!