Tuesday, March 22, 2016

Prototype Surface Mount Soldering Mini-Tutorial: How I do it

Ever wanted to solder surface mount components onto a PCB but were afraid because your soldering iron tip is so big and the pins on the chips are so tiny?  I used to be scared.  But with the right tools and some practice, you can do it!

The approach I use in this video:
- Get chip secured to the PCB using solder paste and a heat gun.  It's okay if we have some solder bridges or not all pins have solder on them at this stage.  The important part is that the chip is properly aligned to the pins on the PCB.
- Apply flux to pins
- Drag solder iron across pins to pull all of the extra solder to one end.
- Remove extra solder using solder wick.  This will not remove all of the solder, just the excess (phew).
- (optional but recommended) Test the board to make sure soldering job is correct.
- Clean off flux using rubbing alcohol or (my favorite) Goo Gone.  Rinse in water while alcohol/go gone has not yet dried (yes, really) and let dry completely before testing.  If white film shows up after drying, it means you did not get all of the flux off so repeat this step until the board looks clean after it has dried.

NOTE : I've used this approach many times for prototype work and it works just fine.  For production work, I'd have a PCB fabrication house assemble the board for you.  I use 4pcb.com.


  1. Great video! I used to be really intimidated by surface mount soldering, but no more. My technique is similar to yours, except I don't use a heat gun or solder paste at the beginning. I hold the part in place with a pencil eraser in one hand, while I tack down a few pins with the soldering iron in the other hand. Then I drag solder, and use solder wick if needed to clean up.

    Nice looking board!