Elenco Soldering Station - Manual (Page 6)

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Surface Preparation
In order for the solder to adhere to the connection, the metals must
be clean and free of non-metallic materials. Flux in the solder can
remove oxides from metal but not other materials like dirt or grease.
To remove these, use a small steel brush or fine emery cloth.
Mechanical Connection
When all the surfaces are clean, the metals should have a solid
mechanical connection.
Wires should be tightly wrapped around
each other or to the terminal. This will eliminate large gaps that create
weak solder joints. Solder should not be used as a mechanical
connection.
Solder
Rosin Core
Solder
Solder is a fusible alloy composed of tin and lead. Some solder may
contain small amounts of other material for use in special purposes
to enhance its characteristics.
Solder has a melting temperature
around 361 O to 370 O , making it ideal for forming a metallic joint
between two metals.
Solder is identified by the ratio of tin-to-lead. The most common
ratios are 63/37 and 60/40. Solder with a greater tin content melts at
a lower temperature, takes less time to harden, and generally makes
it easier to do a good soldering job. The ratio of tin is a main factor in
the strength of the solder joint. Solder with a greater tin content has
a greater holding ability under stress.
Rosin core solders (.031”
diameter) are ideal for use in soldering electronic circuits.
Solder Wire Terminal
INTRODUCTION TO SOLDERING
Almost every electronic device today has a printed circuit (PC) board.
Whether you are assembling a PC board or repairing it, you must
understand the basics of working with these boards.
A poorly soldered joint can greatly effect small current flow in circuits
and can cause equipment failure. You can damage a PC board or a
component with too much heat or cause a cold solder joint with
insufficient heat. Sloppy soldering can cause bridges between two
adjacent foils preventing the circuit from functioning.
Good soldering requires practice and an understanding of soldering
principles. Solder (a tin-lead fusible alloy) is use to form a metallic
union or joint between two metals.
For best results, the soldering iron should be at least 100 O F above the
melting point of solder (361 O F). Generally, a minimum temperature of
650 O F is desirable for printed circuit boards, while higher
temperatures are needed for proper soldering to heavier terminals.
Listed below are some basic steps that should be followed to make
good solder joints.
1. Make sure that the part that is to be soldered is clean.
2. Where possible, make good mechanical connections.
3. Use quality 63/37 or 60/40 rosin core solder. NEVER USE ACID
CORE SOLDER OR FLUX.
4. Apply heat to the base material or wires so that they become hot
enough to melt the solder.
5. Slide the soldering iron away from the joint to leave a neat joint.
6. After removing iron, do not move joint.
7. On temperature sensitive components such as transistors,
diodes, and IC’s, avoid too much heat. Use a heat sink to
dissipate heat away from the component.