Heat shrink tubing is ideal for splicing wires and protecting electrical connections and comes in a plethora of sizes to suit most applications. You can also find a variety of tools that make it even easier to use.
Most heat shrink tubing has a 2-to-1 shrink ratio, meaning you can shrink a tube with a one inch diameter to half an inch in diameter. Once you’ve shrunk the tube it remains at that size, molding itself to whatever it is surrounding. This shrinking and molding action helps protect wire splices and connections from the elements as well as from inadvertent electrical shorts to any metallic objects that might come in contact with the connection.
Heat shrink tubing can be shrunk in several ways, the most effective being a hot-air gun. Hot-air guns are quite similar to the blow dryer you use to dry your luxurious locks of hair, but hot-air guns produce much higher temperatures. People often use small butane torches for shrinking heat shrink tubing as well as they are often smaller and much more portable than hot-air guns. You must be very careful when using either a hot-air gun or a butane torch around flammable liquids and gasses.
The size of the heat shrink is an important factor to consider. Before joining two wires, place the desired size and length of tubing over the end of one of the wires. Once the joint has been made you will then slide the heat shrink tubing over the joint and apply heat to it. Carefully apply even heat to cover and protect the joint.
It is a good idea to practice on a few different sizes and types of joints, splices, and connectors to get a feel for how much heat to apply with the selected size of tubing and heat source before attempting to use this technique in your projects. This will enable you to create much more uniform and functional heat shrink applications that not only protect the wiring, but look more professional than if they were done with simple electrical tape.