From: Randy Dawson <rdawson16@hotmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Thu, 24 Sep 2020 11:54:13 -0700
Subject: Re: [EE] Hand soldering fine pitch packages
Thread-Topic: [EE] Hand soldering fine pitch packages
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What works for me, is the liquid flux, the water soluble stuff that smells =
like citrus.
Tack the corner pins, as you suggest.

Then you can 'rake' the iron down the side of the package, no solder requir=
ed if the PCB is tined.
Solder surface tension solders all the pins without shorts.

Randy

________________________________
From: piclist-bounces@mit.edu <piclist-bounces@mit.edu> on behalf of Bob Bl=
ick <bobblick@outlook.com>
Sent: Thursday, September 24, 2020 11:30 AM
To: Microcontroller discussion list - Public. <piclist@mit.edu>
Subject: [EE] Hand soldering fine pitch packages

What I describe may already be a common practice, but it's something I've j=
ust recently started doing.

When hand soldering an IC, something like a 0.5mm pitch LQFP, I would usual=
ly tack a couple of pins down, maybe brush on a little liquid flux, solder =
the rest of the pins as best I could, then clear all the shorts and even th=
e soldering out with solder wick. Then clean the flux off and inspect.

But lately what I do is skip the soldering part, just go straight to the so=
lder wick. The wick needs to have some solder on it. In other words, apply =
the solder with the product meant to remove solder.

Anyway, I've found it to be faster and cleaner, and uses less solder and le=
ss solder wick.

And, of course, buy the most expensive solder wick you can find.

Cheers,
Bob
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