How to use heat shrink tubing

Heat shrink tubing is a versatile plastic layer that can be applied to components and cabling for several purposes. It's used mostly by electricians, engineers and similar professionals for electrical installation, protection from dust, chemicals, moisture or abrasions.

Reinforcement for cables held at tension and bundling multiple wires into a single unit. Heat shrink tubing can also be used for identification. The wide range of available colors allows for easy coding. When used with cables, heat shrink tubing is also known as heat shrink sleeves. The name itself refers to the fact that tubing can shrink into place, it becomes rigid when heat is applied, and that it offers a protective coating that is durable.

Given the range of possible uses, heat shrink tubing is available in a range of sizes, colors, and shapes. Some heat shrink tubing also comes with an adhesive liner and that helps the tubing to stay in place once it's been applied. If you're planning to use heat shrink tubing, you should watch out for the shrink ratio. This is the relationship between the original size of the heat shrink tube and its shrunken form after application. Usually the ratio is either 2 to one or three to one, and higher numbers can indicate a greater ratio and a tighter fit.

How to Use Heat Shrink Tubing Safely 

When using heat shrink tubing, it’s important that you proceed with caution and observe safety measures at all times. Given that you’re going to be using high levels of heat, you want to avoid accidents or injuries. Here is how you can use heat shrink tubing safely.

• Start with choosing the right size tubing. You need to have the correct shrink ratio that comfortably covers the wire or the components before it has been shrunk into place. This allows for a tighter fit afterwards.
• If the components to be covered can change size after the application, you should ensure that tubing has sufficient expandability.
• Cut heat shrink tubing to the suitable length that you need with standard scissors and lay or slide it over the target components. Once you’ve done that, you can heat the shrink wrap. It can be done with a handheld heat gun, but we’ll go in more into that later.

Types of Heat Shrink Tubing

There are two basic types of heat shrink tubing, single or dual wall. This is also known as thin or double wall.

Polyolefin heat shrink tubing is a popular choice due to its versatility and range of features. It includes chemically cross-linked polyolefin, adhesive-lined options, and comes in custom sizes and colors. This type of tubing is known for its durability and wide range of applications.

Single or thin wall tubing is very reliable and robust. It‘s an excellent choice when electrical installation or protection against abrasions and strain is required. Heat shrinkable tubing can be applied using various methods, with specific temperature and time recommendations for different types.

Double wall tubing, however, is a better choice where protection from corrosion is the aim. There is an additional adhesive layer within the tubing that provides protection against any moisture.

What Size Heat Shrink Tubing Do You Need?

There's a range of sizes that you should consider with heat shrink tubing. These include the following:

• 5mm tubing with a .198 inch diameter is recommended as the size for 12 gauge wire.
• The recommended heat shrink tubing size for 14 gauge wire is the same as that for 12 - 5mm, with a .198 inch diameter
• 3mm heat heat shrink tubing with a 2 to one shrink ratio and a .118 inch diameter is recommended for a 16 gauge wire.
• For an 18 gauge wire you want to choose the same as that for a 16 gauge wire, 3 millimeters or the two to one shrink ratio in a .118 inch diameter.

How to Properly Use Heat Shrink Tubing for Electrical Repairs: A Step-by-Step Guide

Now that we talked to you through what heat shrink tubing is and what sizes you could use, let’s take a look at how to use it correctly on electrical wires. It is crucial to cover and insulate exposed wires to prevent any wire exposure. You will be able to prevent short sparks and other electrical hazards when you use it properly to insulate wires, and in this tutorial, we can guide you through the process of using heat shrink tubing for your electrical repair needs.

Tools Needed:

• The appropriately sized heat shrink tubing.
• A heat gun or a lighter
• Scissors.
• Wire strippers.

Preparation Steps:

• It’s important to first select the right tubing size. Choose a size that’s slightly larger than the diameter of the wire or connector that you are working with so that you get that snug fit after it shrinks.
• Do you need to prepare the wire? So strip the ends of the wire to expose the bare metal and ensure that the wire is clean and free of any debris.
• Cut across a piece of the heat shrink tubing slightly longer than the area that you need to cover so that you have a bit of extra tubing than not enough. Make sure to clean the wire before placing the shrink tube to ensure a tight fit and flexibility once heat is applied.

Application Process:

• Slide the heat shrink tubing over the connector or the wire that must be covered. Before doing so, clean the wires thoroughly to ensure a secure fit. Position the heat shrink tube exactly the way you want it to be before you apply any heat.
• Use either the lighter or the heat gun to apply the heat to the tubing. You should move the heat source evenly over the tubing and rotate it to ensure that all sides are heated evenly. The tubing should shrink and conform to the shape of the wire or the connector.
• Make sure that you allow the tubing to cool down before you handle the repaired area. This ensures that the tubing has shrunk correctly and sealed the wire or the connector in place.

Safety Tips:

You should always work in a well ventilated area. When you are using a heat gun or a lighter. You don’t want to apply too much heat to the tubing either as this can cause it to melt or to burn, which is why you have to keep the heat source moving. The proper tools can ensure that you keep the entire operation safe, so use wire strippers to strip the wire and scissors to cut the tubing. Try not to use any makeshift tools because these could cause damage and that can interrupt what you’re trying to do.

If you’re looking to provide electrical insulation and protection against moisture, then heat shrink tubing will help. You can also use it to repair damaged insulation or seal connectors and that helps to extend the life of the electrical components. Unlike electrical tape, heat shrink tubing offers superior durability, adhesion, and protection against corrosion, moisture, and wear.