Re: First PCB

In article <1140012071.852022.58750@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, "Noway2" <no_spam_me2@xxxxxxxxxxx> wrote:
Most surface mount components, with the exception of BGAs can be
soldered conductively, by hand. The method you use depends on the
device, but in general I use a technique that the instructor refered to
as the dry tack method. A simple example: you want to put an 0805
resistor on the board. First, use a flux pen to put a small amount of
flux over the pads. Next, position the resistor on the pads and press
down on it from the top with a pair of tweezers (small curved ones
help) as does resting one end of the tweezers on a flat surfface. DO
NOT hold the device with pliers or tweezers on the sides - press down
on it from the top. Use your soldering iron and touch it to one end
(pad and component) of the device, which should quickly change
appearance to look wet and then remove the soldering iron. The device
should now be tacked in place. Solder the other end of the device by
placing your solder (wire) where the pad and device meet and then
briefly touch this with the iron and you should get a nice solder
fillet. The amount of solder to use depends on the the solder
thickness and the device size - but I typically use about 1 pad width
with 0.38mm solder on an 0805 part.

Well I guess after doing one, its easier to keep on going. One trouble,
sometimes the part will move while heating the second pad with heat
applied. Holding the tweezer down is sometimes necessary. Little tiny caps
do this easily.

greg
.

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