Hot Air

Recent acquisition of a hot-air rework station, and attendant attempts at surface-mount soldering, have taught me that, to paraphrase Frank Herbert, “God made SMD rework to train the faithful. One cannot go against the will of God.”

In truth, it’s more than a little gratifying once you start to get the hang of it. Spark Fun‘s excellent tutorials help quite a bit. But there’s a point, somewhere around the fifth time you’ve blown a component the approximate size of a fingernail clipping clean off the board, where you start to wonder whether maybe you wouldn’t be more fulfilled collecting stamps or something.

Things (I think) I’ve learned so far:

  • The fact that you’re working on a very small part does not automatically imply that you should use the small nozzle. The small nozzle produces faster airflow, which increases your odds of accidentally blowing a small part about.

  • Don’t overdo it when you dome a pad in preparation for soldering down a component. Soldering through-hole parts using an iron accustoms you to using lots of solder as you build joints. SMD is all about very thin layers of solder pulling components into place via surface tension. Excessively generous domes just get squished by your component’s lands, sending solder to places where odds are you didn’t want it.

If I succeed in my current rework attempt, I might actually attempt to build something new next.

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