22 Dec
2007
22 Dec
'07
11:15 a.m.
On Saturday 22 December 2007 02:52, Roy J. Tellason wrote:
On Friday 21 December 2007 16:54, Chuck Guzis wrote:
The way that they taught us to do it in college was basically the same
way, except using solderwick to pull up the excess, instead of a solder
sucker.
The technique was basically to tack down the corners of the chip first,
so that the chip is/stays properly aligned with the board, and then
drag the soldering iron along each side (using a wedge tip), with the
solder along the trailing edge.. if you get just the right speed,
you'll get a good connection. Then, just take solderbraid and an iron
to pick up the excess.
It works, and unless you're careless (or using a 100W soldering gun or
something), it works pretty well, once you've tried it a time or two.
Pat
--
Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
Two approaches that I've seen for
conventional soldering iron
mounting involve what I'll call "flood and suck" that involves
covering all of the leads on one side of the QFP on the PCB with
solder and then using a solder "sucker" (such as a Soldapullt) to
remove the excess.
I've *never* heard this recommended. And with that setup you're
talking about pulling the solder out between the part lead and the
trace without pulling the trace off the board. I wouldn't care to
try it.