Making PCB's is a Pain in th... A Whole Lotta Fun.

I've been testing a prototype (update) of my "Bento Box" style filter, which uses a neat ESP32 dev board that integrates a couple MOSFETs (perfect for fan control), and a nice 5v buck and 3.3v regulator.  Overall the board has been working well, but I really hated soldering the thin wires I was using to it.  I really suck at soldering, so I thought I'd try building a breakout board to slap on the dev board and make the connections somewhat simpler.  It still requires soldering, but soldering headers is much simpler than dealing with the thin wires I was using (due to an I2C hub that used JST-SH (1.0mm pitch) connectors.  Anyway, the last time I designed a PCB was when Eagle was the tool to use, and it seems that the baton has been passed to KiCad.  I'm sure Eagle was just as frustrating to get started with as KiCad has been, but if you ever use it, I have one suggestion - get the "Freerouting" plugin.  I thought it would have an autorouter integrated, so I was puzzling over where it was, until I asked AI and discovered it's a plugin.  That was an hour I won't get back, but so you won't also spend an hour messing around trying to find it, here is how to install the "Freerouting" autorouter plugin:

1. From the Main Screen for KiCAD, go to "Tools" > "Plugin and Content Manager":

2. Search for "Freerouting" and install it.  But make sure to install the Java JRE first, since I found the install hung until the JRE was installed. 

3.  To run the autorouter, it can be found under "Tools" > "External Plugins" > "Freerouting" from the PCB editor in KiCAD:

That is just the autorouter though, don't get me started on all the BS Design Rule Checker (DRC) rule violations I had to fix.  The DRC is handy and there was a similar tool in Eagle, it basically checks the PCB to make sure the manufacturer won't reject it for some design issue.  It does all the basics like checks if a pin is not connected or if some silksceen text is off by half a damn mm, but also some very esoteric (and annoying) stuff.  I spent the better part of the evening chasing down DRC errors until I finally slayed the last one.  All that said, KiCAD does work well (a bit buggy with a few things), but it is a nice package and pretty well polished.  If you want to build a PCB though, it pays to expect problems and schedule accordingly, since the learning curve is always a bit steep (and frustrating) with software like this.

But with all that wasted time, I now have a neat breakout board design that can act as an I2C hub (for three devices), breaks out all the worthy GPIO pins, has some cool LEDs (purely optional), and an optional power load switch IC, which I put on it at the suggestion of my AI buddy who said why not?  Aparently it can be handy if I2C devices lock up or get confused (they can be power reset through a GPIO from the ESP32 when it detects no data is flowing).  I tried to keep everything that was required for the basics to work as through hole components, while the optional bits are SMT (but aside from the SOT-23 package for the IC, they are all 1206 SMD parts).  KiCAD was able to export the board as a STEP so I could verify it would fit with my other models too, which was pretty cool.

I expect to have a few projects coming down the pike using this ESP32 dev board, related to 3D printer air quality monitoring, printer exhaust filtering or ducting, which will have integration with Home Assistant (for automation).

​I haven't priced out what this will cost to make, but I'm gonna give it another once over this week to make sure I didn't mess up some pinout or something stupid.  Then I'll probably order a small batch to test out.  I need to look up who the best companies are to order from.  I see a lot of ads for JLPCB and PCBWay, so I will check them first.  The breakout board will require some JST-PH connectors and some pin headers, along with a couple small though hole ceramic capacitors, which I will also need to order now that the bill of materials is set. 

All this begs the question though, why make a breakout board (which requires soldering to assemble) if you suck at soldering?  For me at least, there is a big difference between trying to solder tiny wires that really shouldn't be going into a board (aside from a prototype), and soldering pin headers which are much simpler to deal with.  Even though I suck at soldering, I can make a reasonable effort at soldering a pin header.  To help with my technique, I also decided to pick up some real flux to help me with this project, since I typically use flux core solder, and some decade old flux paste, which is not ideal.  One tool I have that absolutly rocks though is my Alientek T80P USB-C soldering iron.  It gets to 350°C in seconds.  Before I can get my bearings on what I'm soldering, it's ready to go.  It does require a beefy USB-C PD supply though (I use a 100w battery power bank since I like to work outside when possible).