Bunnie investigates! And other readers chime in with their experience with ripples found on PCBs.
So here’s my quandary: are the ripples intentional (for example, an attempt to increase current capacity by selectively thickening fat traces with a solder coating), or accidental (perhaps microscopic flaws in the soldermask allowing molten metal to seep under the soldermask during wave soldering)?
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.