NR NR/L3/SIG/11303/1H15 ISSUE 2 PDF

Introduction

Solder is a low melting point metal used to join together other metals. To obtain a good joint the solder should:

• Flow between the metal surfaces (which need to remain unmelted).

• Completely fill the space between surfaces.

• Adhere to the surfaces.

• Solidify.

It is essential, therefore, that:

• Each of the surfaces to be joined is wetted by a film of solder.

• The films of solder are continuous and the space between them is filled with solder.

The rest of this module will show how to achieve these essentials. Make sure you can produce good results before you work on signalling installations.

Practise on dummy jobs until you can produce perfect joints every time.