The boards have arrived:
It’s covered in lead
The default surface finish option when ordering from JLCPCB is HASL with lead. I did so many dry runs through the ordering process that I forgot to pick ENIG. Now all the lovely pads that people are supposed to hold onto are coated with lead. I aim to address this by conformal coating the text, and 3D printing coverslips to go over the finger pads:
Since I don’t trust the conformal coating not to scratch off under constant rubbing.
Actual functionality
Seems fine as far as I can tell. Have not programmed all the PCB’s yet, but the few that I have operate fine. I got claude to add a self check program to see that data was coming in from the imu, compass and gps as well as that a valid i2c transaction could be issued to the screen. All boards have worked so far.
Personalised names
I’ve laser etched the name of each of the attendees on all the PCB’s. Here is a zoomed in photo of one of the letters:
Pretty good!
Conformal coating application
Here is the mask I used to only apply the coating to the writing:
I thought about selectively masking out the switches, USB port, screen, and battery holder selectively so that the whole board could be coated but it seemed like less effort to just selectively coat the center text instead.
The conformal coating needs to be cured for a while so to get it done faster I built a small hair dryer powered incubator in which all the PCB’s could be stacked at once and held for 50C for a few hours to cure them:
Here are the stacked racks, which together with the floor of the cardboard box was just able to accomodate the 40 PCB’s.
Here is the box in operation:
Nice and toasty.