Solder a wire
Wiring layouts and accessories usually requires soldering, but it’s nothing to be afraid of – George Dent goes back to basics to show you how to make a reliable electrical joint.
George Dent goes back to basics to show you how to make a reliable joint.
Nothing puts more modellers off than the prospect of soldering, be it wiring a layout or assembling a kit. Yes, it’s a technique that requires a little practice and foreknowledge to get right, but it can soon be mastered and the possibilities that it offers are almost endless. To dispel the myths, let’s have a look at the very basics: preparing the surfaces and getting the solder to flow. Whether we’re converting a locomotive to DCC or simply repairing a broken wire, soldering will produce an instant, enduring and fully conductive joint without the need for bulky screw connectors or reams of insulation tape. Soldering irons are fairly inexpensive, although choosing the right one for your needs is important. For most hobby tasks, an 18-25 watt tool will suffice and brands such as Antex and Weller are recommended. Nimrod and Dremel also offer cordless irons that are powered by butane (as found in cigarette lighters), and these can be a great help when working on far-flung corners of a layout. The size of the iron’s tip is also important, as a bulky wedge of metal will cause problems in a confined space. Some of the better iron manufacturers offer interchangeable tips. You must also be sure to choose the right solder as some melt only at specified temperatures. For general electrical work, a regular 60/40 resin-core solder will be suitable, preferably of around 0.7-1mm diameter. Flux is an acidic solution that, when heated, penetrates the joint and takes the molten solder with it, creating a more reliable joint. It also allows the iron to be in contact with the subject for a shorter amount of time – something highly desirable where plastic and delicate components are never far away. Flux comes in powder, paste or liquid form; paste is the better option for electrical tasks as it’s easier to apply and clean up.