David Griffith asks:
One reason I never graduated to /real/ soldering
stations is
that I kept wondering "what do I do when it goes bad?". What
do you guys recommend?
I really really like the Weller WTCPT line of soldering stations.
There is very little "smarts" in the soldering station. Temperature
control is supplied via a purely magnetic-electro-mechanical feedback
loop - when the tip reaches a certain temperature, a special alloy in
the base of the tip becomes non-magnetic (Curie point) and the
heating circuit opens. When it cools down below the Curie point,
the heating circuit closes. Different tips are available with different
temperatures.
I like these soldering stations purely out of inertia - I've been
using them for decades. I don't think they're nearly as good
for, say, extensive surface mount rework as a Metcal station that
costs 10 to 20 times as much. But they do just wonderful for my
uses, working on everything from vacuum-tube electronics to DIP
circuit boards to some surface mount stuff. Different tips are
available; I love the big fat tips for working with vacuum tube
electronics because with them the WTCPT is the equivalent of a 100
watt soldering gun, even those big fat joints heat up real fast. For
finer detail stuff I sometimes switch to finer tipped points on the
WTCPT but very often I find myself using the big fat tips just because
I'm so used to them.
I am one of those rare guys who do not use super skinny solder with
super skinny tips to do real-fine pitch soldering. In some rare
circumstances - 0.25mm pitch SMD - I will switch to the finer tip.
But more often than not I'll just stick to the humongous fat tips and
big old fat 0.063" thick solder. One of the reasons I stick with the
big fat tip, is that with 0.25mm
pitch SMD stuff I find that the big fat tip will simultaneously heat
up all the pins on one side of a chip :-).
Why do I not recommend them for extensive surface mount stuff? Because
the magnetic tip has this annoying tendency to suck up any 0603 or 0402
or 0201 SMD parts which have any steel component in them. For extensive
surface mount stuff a non-magnetic tip would probably be nicer.
The WTCPT's are dead-bone stupid - no digital display to mess up; no
knob to twist for different temperature; no thermistor; cord is
unmeltable. All of mine are between 10 and 30 years old - I bought
myself a brand new one once, the others I got with a decade or two
of use already on them.
The WTCPT's one weak point is the connection from the iron to the
soldering iron station base (which has little more than a transformer
in it.) This is a plastic plug/jack that can break under extreme abuse.
I've collected a couple WTCPT's over the years with a broken plastic
plug or jack, and fixed them by simply soldering the wiring straight
through without a jack.
Tim.