A5: Making PCB: A Tale of Failure, Woe and Learning

Failing and learning

This is a story of how I started with the plan of milling a simple circuit and somehow ended up messing up, losing it, feeling discouraged and incompetent, forgetting to document, milling 6 more and messing that up too, and learning a lot in the process.

It all started here: We were in class last Thursday, designing a simple circuit together. It was going well. "I got this!" I thought. "I'll mill it later and solder the tiny parts tomorrow." Little did I know that this simple plan wouldn't turn out as expected.

First round: failed and undocumented

I do not even have pictures for the first board I milled. I did it on Thursday afternoon, and kept the machine settings that Blair and Danli had used before me. It went well. Nadya later told me that my edges were too far from my ground and power pads, which I fixed in the next design.

The next day, after group meeting and electronics sorting, I soldered my SM parts to the board. I did a poor job, and perhaps fried the LED. I was so disappointed with myself at that point that I forgot to document the whole thing. I think I also had a confused understanding of what we needed to deliver on that week, a confusion that probably partially stemmed from my feeling of failure. Worst of all, I ended up losing the PCB (in my bag? in Sieg 4th floor? in the lab?) and therefore all tracecs of that early work.

Second round: failed and documented

On Sunday I went to the MILL and milled new boards. I milled 6 because I figured I might need some practice with SM soldering. First step was loading the files, the material, installing the endmill, and adjusting the machine settings.

An important thing that happened is that the material offset was off, because I somehow read the Z material offset as being the XY material offset. When it was time to mill, I was surprised to see the endmill move in the air, about 5 mm about my board (eye roll). I didn't even realize that that was the issue until the next day, Monday, when I set up the lab's Othermill at home and the same thing happened.It's embarassing to admit but here it is. I read too fast, or wasn't paying attention, and ended up with weirdly milled boards because I was eyeballing the distance between the endmill and the board and manually inputing it via placement offset.

Another "funny" thing that happened was that while I was vacuuming I accidentally vacuumed two mini boards, ending up with 4 boards instead of 6.

The next part was the actual soldering. I watched this tutorial and it helped a lot in better understanding what needed to happen. It seems obvious when you know it, but isn't so when all you've done is big pieces soldering.

Not a great soldering job...

And it didn't work... My guess is because the solder is not just on the pad but gets onto the rest of the board?

So what did I learn?

That the Z offset is in fact the Z offset, not the XY offset. It somehow wasn't clear enough or I wasn't paying enough attention.

That even when you fail, you need to document (perhaps especially when you fail).

That sometimes fatigue and discouragement get in the way; to recognize that they do and work with that knowledge.

#SolderingGoals