A little knowledge about stripping and splicing electrical wires can be a tremendous help if you're installing electrical accessories, or repairing damaged electrical wiring. Here are some basics.

Electrical wiring used in automobiles is referred to by its gauge number. Common gauges used are 16, 14, 12, and 10. The gauge number refers to the diameter of the wire, not to its length or weight. As the numbers get smalled, the diameter of the wire gets bigger. A 14-gauge wire is thicker than a 16-gauge wire, and a 12-gauge wire is thicker that a 14-gauge wire, and so on.

It's important to use the right gauge wire. You don't want to used a 10-gauge wire, and by the same token, you shouldn't use a 16-gauge wire in place of a 10-gauge wire. Using the wrong gauge wire can damage components and can be dangerous. For exemple, a thin wire carrying too much current could burn in tow.

How do you know what is the correct gauge to use in a given situation? There are various ways to determine which gauge is correct. You can ask a mechanic. Or you can cut off a short piece of the wire in question (say you're replacing a damaged section of wire, for example), take it to an auto parts supply store and have the parts man give you replacement wire of the same gauge, or you can use a wire-stripping and crimping tool to determine the gauge.

A wire-stripping and crimping tool is a handy device. It will cost a few dollars, but lasts indefinitely. And you really need it to do a safe, professional job splicing wires. It's available at auto parts supply stores, too.

Use the cutting part of the tool to cut off a short piece of the wire. There are various holes in the tool with numbers beside them to indicate the gauge number of the wire.

With a little practice you can look at a wire and almost always pick the right gauge hole on the tool. But the first few times you may guess wrong.

Open the tool a little bit (it opens and closes like a pair of pliers) and stick a short piece of the insulated wire in what you guess to be the correct hole in the tool, close the tool by pressing the handles together, and peel the insulation off with the tool.

What will happen if you picked the correct gauge hole in the tool is that the tool will cut through the insulation, allowing you to slide the insulation off the end of the wire easily. It will not cut into the wire itself. If it does cut into the wire, and a few strands of wire come off with the insulation, you picked a gauge that's too small. Try the next biggest hole.

On the other hand, if the tool is closed, yet doesn't quite cut all the way through the insulation, you've picked a hole that's too big. Try the next smallest hole.

You known you've got the right gauge hole with the tool when you can cut through the insulation cleanly to the wire, and slide the insulation off, without cutting through any wires. This, then, will tell you the gauge of the wire you're working with.

This tool can be used to fasten two electricl wires together with an item that's called a butt splice. To do that you strip a short piece of insulation from the end of each of the two wires to be spliced together.

Then you stick each end of the wire in the butt splice and crimp the butt splice together, using the crimping part of the tool (those notches at the end of the tool).

A butt splice is basically a hollow tube. It accepts a wire in either end, and then when it is crimped, it holds the wire together. Be sure and use a butt splice that is the proper size for the wires you are splicing together.

Butt splices can be purchased at auto parts supply stores. Tell the parts supply stores. Tell, the parts man the gauge of wire you are working with, or show him, and he'll give you the correct size butt splice. If in doubt about exactly how to use the tool, and where to crimp the splice, ask him to show you. It is easy, and will only take him a moment.

Butt splices work well where a wire isn't subjected to stress and strain.

Stronger however, and what you need if there's some question about whether the butt splice is strong enough, is a mechanical splice that's soldered together. We'll deal with those another time.