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4.4 Handling
Use suitable soldering wires and handle the soldering station in a correct way. This is
prerequisite for impeccable soldering operation. We recommend electronics soldering
wires with colophony solder core. In no case solder cores should contain halogens.
The solder core within the solder wire liberates the soldering spot from solder-inhi-
biting contaminations and oxides and prevents the producing of new oxide during
soldering.
The most commonly applied electronics solder is the Fixpoint
®
leadfree solder wire
of Goobay
®
solder wire L-SN 60 Cu 2 (DIN EN ISO 12224-1) with a tin content of 60%
(60/40 solder). This solder is available in different wire diameters (0.56 - 1.5 mm). We
recommend a solder wire diameter of 1 mm for electronics.
Before using the soldering station the first time, burn the soldering tip
free of production residues and tin-coat it. Therefor switch on the
soldering station and let some soldering tin deliquesce at an approx.
temperature of 200°C to a thin connected film on the soldering tip.
The correct soldering temperature is crucial for the quality of the soldered spots. In
electronics the common soldering temperature is 300 - 380°C. Too low soldering tem
-
peratures lead to cold solder joints. At too high soldering temperatures the solder core
burns in a way interrupting the solder flow. Moreover, there is a danger of damaging
the circuit board and other components caused to these high soldering temperatu-
res. Wipe the soldering tip directly before soldering with the moist cleaning sponge.
Remains of incompletely vapourised solder cores, oxides and other contaminations
will be removed this way.and dissapear from the soldering spot. Before replacing the
soldering iron to the stand after work, the soldering tip has to be cleaned again and
be tinned with some new solder. It is important to hold the soldering tip always tinned
because otherwise it will become passive after a while and disable to absorb solder
anymore.
1. Hold the cleaned and well tinned soldering tip, heated up to the set
soldering temperature, to the soldering wire and to the spot being solde-
red.
Now the solder core flows and cleanes the surface of the metal parts being
soldered and then the soldering tip in order to make the electrically conduc-
ting
connection.
The soldering time in electronics is not longer than 2 seconds. A good
soldering spot in cooled status looks smooth and shiny after the removal of
the soldering iron. Poor, defective soldering spots look dull, uneven and
brittle after cooling-down. Beside the application of unsuitable solder or a
too high soldering temperature set, defective soldering spots often occur
due to too short or too long soldering times.
A soldering spot may not be heated too long. On the other hand do not take
away the soldering iron from the soldering spot too early, but only when the
soldering tin flows like bare silver.
2. After finishing the soldering, leave some solder at the soldering tip be
fore placing it into the holder and switch off the soldering station.
The remaining solder will then be wiped off the hot soldering tip by the
moist cleaning sponge before starting the next soldering operation.
