SparkFun Midi board soldering
This is my successful attempt at soldering a Sparkfun MIDI Shield (DEV-12898) with Adafruit Extra-long pins (P400A), using Lead-free solder (Sn 96.5, Ag 3, CU 0.5; flux 2.2%; 0.2mm dia), cleaving up with Rubbing Alcohol & cotton swabs. I used a Hakko FX-951 soldering iron & the default chisel tip (set to 750 deg) and a Weller Smoke Extractor.
Testing was done by transmitting pair of MIDI packets, over and over from an NXP LPC802 OM40000 board, to the Sparkfun board and then into a Korg Volca keys. Note that I had to wire up the individual pins because the LPC802 board doesn't have a direct connection from UART TX to the Arduino header. If I had used an Arduino R3 Uno it would have been direct.
The Adafruit extra long headers were used instead of the standard Arduino headers because I wanted to have test points on the top of the MIDI board so that I could do signal tests using my Saleae logic analyzer.