From: Bob Blick <bobblick@outlook.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
Sender: "piclist-bounces@mit.edu" <piclist-bounces@mit.edu>
Date: Thu, 24 Sep 2020 15:24:20 -0700
Subject: Re: [EE] Hand soldering fine pitch packages
Thread-Topic: [EE] Hand soldering fine pitch packages
Thread-Index: AQHWkp98x1dZkvwAL0m2+gFZ1v5Uwal4U/WAgAAH7xM=
Message-ID:
 <BYAPR02MB4055F735B7F2385F1F25770DDC390@BYAPR02MB4055.namprd02.prod.outlook.com>
References:
 <BYAPR02MB40550B27C1CB73D0A16160ABDC390@BYAPR02MB4055.namprd02.prod.outlook.com>,
	<CAFEth_xPA6tE=M39tSVK2a_QQgnVSaD1tBtTJKakA05HfOga8w@mail.gmail.com>
In-Reply-To:
 <CAFEth_xPA6tE=M39tSVK2a_QQgnVSaD1tBtTJKakA05HfOga8w@mail.gmail.com>
Reply-To: Microcontroller discussion list - Public. <piclist@mit.edu>
Accept-Language: en-US
Content-Language: en-US
X-MS-Exchange-Organization-SenderIdResult: Pass
X-MS-Exchange-Organization-PRD: mit.edu
X-MS-TNEF-Correlator:
acceptlanguage: en-US
received-spf: Pass (protection.outlook.com: domain of outlook.com designates
	40.92.9.44 as permitted sender) receiver=protection.outlook.com;
	client-ip=40.92.9.44; helo=NAM04-BN3-obe.outbound.protection.outlook.com;
dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=outlook.com;
	s=selector1;
	h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
	bh=6LLXdX5MxPi2S68C3TK75S8Y++KoXyiU5USkVTwlEOU=;
	b=M3qh3Xk6EjgL/MQNxOds8ss77wuQld7rQvvjb+XRPM3mZV9ezRzppxS31+Qd+xdG1H4lMos6aIUG+Z7XvjRZoAbcxW1MZwST+JN7AyY8IBq/gzPniuFcHbbJganFj97I6c8LT7R1G1B1e+46wIKT3mBhjaH0M3MnTkxwVGftTMMmysg3Kv0i/uGHveG51EdpFjTl7WWKlq4PmD0gNDzktLKnOm/OpRnha530XckMpfeF2CqgmeGq3f7CVUHqdAgymLrfg2I6EB2aE6MLCoeQskuPvzd/7uEE6m0YxZavT2FAKsfAmAt+5VN81yR2oSJYxY3oLsp6XZYphdk2pH+P2w==
authentication-results: spf=pass (sender IP is 40.92.9.44)
	smtp.mailfrom=outlook.com; mit.edu; dkim=pass (signature was verified)
	header.d=outlook.com; mit.edu;	dmarc=pass action=none
 header.from=outlook.com; 
errors-to: piclist-bounces@mit.edu
list-id: "Microcontroller discussion list - Public." <piclist.mit.edu>
list-post: <mailto:piclist@mit.edu>
x-beenthere: piclist@mit.edu
x-mailman-version: 2.1.6
x-topics: [EE]
x-mime-autoconverted: from quoted-printable to 8bit by PCH.mit.edu id
	08OMOOw0014790
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0

Give my method a try sometime. It uses far less solder and solder wick, but=
 the real advantage for me is less cleanup. Flood filling adds a lot of bur=
ned flux. With my method, you only need to use a little bit of flux, and th=
e solder on the wick has no remaining flux. And while you are dragging the =
wick, it's doing the soldering and pulling some of the fresh hot flux away.

Anyway, I suggest giving it a try. So far I haven't decided which direction=
 to face the wick works best, facing in, out, or sideways from the part.

Friendly regards, Bob

________________________________________
From: piclist-bounces@mit.edu <piclist-bounces@mit.edu> on behalf of K S=20
Sent: Thursday, September 24, 2020 2:49 PM
To: Microcontroller discussion list - Public.
Subject: Re: [EE] Hand soldering fine pitch packages

I flood (like really flood) the entire row with solder, let it set, then
place the PCB on its edge so the row is now vertical and slowly remelt the
solder from top to bottom. The surface tension collects the excess on the
way down and usually, for a 0.4mm pitch, only the last 2 or 3 pins require
a touch-up with wick. For all four rows of a 120 pin QFP this usually takes
a lot less time than the aligning part. Extra flux not usually required.
Make sure you don't drop the molten blob of solder at the end on other
parts of the board.
--

--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.