Main Board Version Two

I spent the last two evenings updating the Main Board schematic and PCB layout. I deleted all the labels and manually placed wires for every connection. But this caused problems: I could no longer see helpful net information as I laid-out my circuit, it wasn't easy to tie thermal features into a ground-plane (since my ground plane was now some randomly-labeled net), and the schematic was basically unreadable. So, then, after laying out the circuit board, I decided to double-back and I added back all the labels into my schematic. I'm still not sure whether it was my net-labeling that led to the screwed-up boards from before. I manually checked the laid-out board for missing connections until my eyes were bleeding but didn't find anything.

I tried several different methods for adding thermal-relief vias but the method that is well-described in this video is what I ended-up using. There doesn't seem to be a settled method in KiCAD for adding thermal vias, so googling a solution and decided what to do is somewhat intimidating for a novice like myself, especially since I lack a firm grasp of even the fundamentals of what I'm trying to do.


It's probably hard to see in the above, low-resolution rendering of my board but I have ground-planes and thermals near the motor controllers. I also eschewed use of the auto-router and managed to end up with only six or so signal-trace vias. Pretty exciting!

So, the main problem I was attempting to solve in this revision was that the motors were barely turning. I had to bodge a wire onto the motor controller power-supply pin so I suppose I never did get an accurate assessment of the board. But I assumed that the my .25mm traces were not adequate and I quadrupled that to a 1mm trace. But, using this trace-width calculator, it seems that .25mm traces should have been more or less adequate, assuming that the motor draws 250 milliamps or so. I guess that there are probably potential issues for too-wide traces (including current loss?). So here's hoping that this revision drives the motors okay. I did at least keep the wide power traces very short.

So, while I wait on this board, I will test the remaining features of the turret board and fix all the issues I have encountered.

I started a repo for my circuit designs. The main idea here is to check-in my design whenever ordering a board so that I can always reference a design associated with a particular physical board.

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