2torial #0927:
Learn2 Wire a Lamp

Let there be light

The bulb isn't the only part of a light fixture that burns out. The wiring can get old and cracked, sockets can short-circuit, and plugs can break. The good news is that you can fix all of these problems with a quick, inexpensive trip to the hardware store and about ten minutes of work. We'll show you how to safely raise your lamps from the dead, as well as how to create a few new variations on the theme.

Fixing anything electrical requires precise workmanship. One stray wire or loose connection and sparks can fly, which could result in something a lot worse than a burned-out light socket. When following these directions, take your time, use quality materials, and be exact.

Note: The wiring procedures in this 2torial are for a stand-alone lamp with a single incandescent lightbulb only. Unless you're a trained professional, don't attempt to rewire any electrical fixtures that are a part of your home's central wiring system (outlets, ceiling lights, fluorescent or track lighting, and so on).

Dismantle the lamp

If your lamp is broken and you've ruled out the obvious (like a dead bulb or wall outlet), it's time for a little surgery. Here's how to remove and check the old electrical socket:

Unplug the cord (never tinker with anything plugged in), remove the bulb, and take off the lampshade.

You should now have a clear view of the electrical socket, made up of the socket hole, into which the bulb screws, the tube-like shell surrounding the socket hole, and the cap at the end opposite the hole, through which the cord enters. There are two main types of sockets: plastic and metal. To open either one, first loosen the tiny screw (turn counterclockwise) on the side of the cap, beside the entry hole for the cord. This screw holds the cord in place.

If the socket is metal, work your screwdriver between the cap and its shell. With a little tugging, these two pieces should separate fairly easily. If the socket is plastic, unscrew the cap from the shell.

Once the cap is separated (although it'll still be somewhat attached, since the cord still threads through it), you'll see the electrical insert within the shell. It should slide out if you tug gently on it while pulling the shell the other way. The insert is where the electrical wires connect with the socket via two terminals--two screws attached to opposite sides of the insert.

When the insert is out, check the wire connections. About 1 to 2 inches (2.5 to 5 centimeters) from its end, the cord should split in two, with the plastic or rubber stripped away about half an inch (1.25 centimeters) from each of these ends, exposing two bundles of copper wire. Each bundle should be wrapped clockwise underneath a terminal screw's head. If either of the bundles has burned edges or is loose from the screw, your socket may not be broken. See Step 2 for how to split and strip the wire.

If the connections look solid, the socket is probably dead. Loosen the two terminal screws and remove the wire bundles. If the ends of the split cord are tied in a knot (called an Underwriters' knot, used to secure the cord in a socket or plug), undo the knot and pull the unattached cord through the cap. Keep the cap and socket so you can compare to make sure the replacement matches its size. If the cord looks sturdy, without any cracks or frayed areas, you can reuse it with the new socket. If it doesn't, leave it in the lamp--you can use it later to thread the new cord through the lamp's interior.

Prepare the cord

To properly wire a lamp, you need a soundly split, cut, and stripped electrical cord. You can buy a new cord at a hardware store (ask for lamp cord--it's usually sold by the foot and comes in a variety of colors). Buy enough to connect the lamp to the nearest outlet.

To prepare the cord, use a sharp knife to split the last 2 inches (5 centimeters) of one end of the cord, slitting down through the narrow groove in the center. You should end up with two sections, each containing a bundle of tiny copper wires (don't cut into the wires).

From each cord section, strip away about half an inch (1.25 centimeters) of the plastic covering from the very ends, so the copper wires are exposed. Do this carefully--you don't want to cut or fray the wires. Use your knife to score the circumference of each section, cutting through the majority of the plastic sheath but not quite deep enough to reach the wires inside, then pull the end of the sheathing using your fingers or pliers. The plastic should tear away, leaving you with the stripped copper wires.

Your two cord sections should now have stripped wires at the very ends. The exposed copper wire should all be the same length, without any frays. Twist each wire bundle together clockwise. This will make them easier to attach to the terminals.

Note: On one section of the sheathing, you'll see a groove or stripe marking the neutral wire, with the smooth section marking the hot wire. The hot wire is live, carrying electricity from the wall outlet to the lamp; the neutral wire completes the circuit by carrying the electrical current back to the wall outlet. To wire the lamp according to electrical code, the hot, smooth wire should be connected to the brass terminal screw, and the neutral wire to the silver terminal screw.

If you're buying a new cord, you'll probably need to buy a new electrical plug attachment as well. A standard lamp needs nothing stronger than a two-prong, 120-volt plug (don't buy a three-prong plug--you need a special cord for these). These are also sold at hardware stores and are easy to attach. Split and strip the cord in the same way as directed here, except split only 1 inch (2.5 centimeters) from the end. The plug should separate into two parts, either by loosening screws or undoing clips (follow the directions).

Once you have access to the inside of the plug, you should see the terminals (two small screws) onto which you attach the stripped wire. Follow the same wiring procedures outlined in Step 3 (including tying the Underwriters' knot once the cord is inserted into the plug's casing, and connecting the hot wire to the brass terminal and the nuetral to the silver terminal), reattach the plug's casing, and you're done.

Rewire the lamp

Time to get the juice flowing. Wiring a lamp is similar to dismantling a lamp, except it's done in reverse.

If necessary, use the old lamp cord to thread the new split and stripped cord through the lamp body and nipple. To do this, use a knife to sever the plug from the old cord, attach the beginning of the new cord to the end of the old one with a piece of masking tape, then pull the new cord through.

Note: If the lamp has a harp, check to see if the harp's base, or the whole harp, needs to be attached to the lamp before the cap.

Thread the new cord through the socket cap (remember to loosen the small screw located beside the cap's hole), then tie the cord in an Underwriters' knot. To make the knot, make a loop with half of the split cord, looping away from where they join. Slip the stripped ends of each cord half through the opposite loop, and pull the ends tight.

Once the knot is tied, remove the socket's electrical insert from the shell and loosen the terminal screws with your screwdriver. Twist the exposed copper wires of each cord clockwise around a different screw, just below the screw's head. Connect the hot, smooth wire to the brass screw, and the neutral wire to the silver screw. Make sure the copper wire is wrapped tightly together under the screw head.

Note: Precision is key here. Wrap the wire so the edge of the plastic sheath (where you cut to strip the wire) butts the screw head. There shouldn't be any stray copper wires running out from beneath the screws. Wires from one cord should never touch wires from another.

Tighten the screws so the heads clamp down on the copper wire to hold it in place.

Slip the wired insert back into the shell and reattach the cap. (Secure the cap to the nipple first, if necessary.) The cord should pass through the cap into the shell. If the socket is plastic, the cap should screw on. If it's metal, it should fit snugly over the shell's end. Tighten the small screw where the cord enters the cap.

When everything looks secure, plug in the lamp, screw in a lightbulb, and give it a test. If you have light, congratulations! You've successfully brought your lamp back to life. Read on for instructions to help you create either a hanging lamp (Step 4) or a glass bottle lamp (Step 5).

Create a hanging lamp (optional)

Once you have the basics of wiring down, you can experiment with a host of new lighting possibilities--the first of which is the hanging lamp.

Decide on placement. With a power source, enough lamp cord, and a secure hanging spot, you can put your hanging lamp anywhere you like. However, since you don't want too much unsightly cord, try to keep its placement near either a wall outlet or a ceiling light fixture (with a standard bulb socket)--either will work as a power source. To figure out how much cord you'll need, measure the distance from the power source to the ceiling hanging point, and add it to the distance from the ceiling point to the lamp.

Gather your materials. Buy the correct length of cord and a two-prong plug attachment. For the socket, you have a variety of choices: You can buy ones with on-off switches connected to the socket, such as a turn knob, a push button, or a pull chain; or you can get a keyless socket, which has no switch (these work well if your power source is a ceiling socket with its own wall-mounted light switch). Finally, you'll need screw hooks to hang the lamp from the ceiling, a lampshade that can attach to the cord, and a lightbulb.

Note: If your power source is a ceiling- or wall-mounted light fixture, you'll need a plug body adapter, which you can find at a hardware store. This inexpensive device screws into a standard lightbulb socket, but has a prong receptacle on it that converts the socket into an outlet.

Wire the socket, cord, and plug. Follow the procedures outlined in Step 2 and Step 3 for preparing and wiring the cord, socket, and plug. Before you start, however, check to see at what point the lampshade will need to be attached to the cord. You can attach some models after the wiring is completed, while with others, you'll need to thread the cord through the shade before attaching the socket. Whatever the case, never rest the shade directly on the socket. Once the wiring is complete, test the lamp before you hang it.

Hang the lamp. Secure your hook screws to ceiling joists to ensure a safe suspension, and hang the cord so it's out of the way, flush with the wall or ceiling. Wrap the cord around the screws so the lamp's weight won't pull on the plug in the outlet. Plug it in to the outlet or adapter, turn it on, and enjoy your new light source.

Create a glass bottle lamp (optional)

Maybe you've bought a lovely antique bottle, thinking you'll someday find a use for it. How about using it to create a lovely lamp?

Gather your materials. A thick, sturdy bottle with a wide base (for stability) and a fairly narrow neck and mouth (to hold the nipple rod) works best. Bottles with mouths larger than 1 inch (2.5 centimeters) in diameter won't work for this project. Buy enough lamp cord to reach the nearest outlet, and don't forget the plug attachment, lightbulb, and lampshade (if you want one).

You'll need a special socket that has a side hole, so the lamp cord can enter it without having to travel through the bottle. You can find these sockets at lamp stores if your hardware store doesn't carry them, as well as lamp nipples and shades. Make sure the nipple you buy fits snugly into the bottle's neck, and that the shade works with the bottle's size.

Attach the nipple. Slip the nipple rod into the bottle's neck so the rubber adapter is flush with the top of the bottle's mouth. There should be enough threads on the exposed part of the rod (outside of the bottle) to screw the socket onto, and the lamp harp, if necessary. Tighten the top nut above the adapter with a wrench by turning it clockwise. This will push the adapter against the nut below it, causing the rubber to expand and fit tightly within the bottle's neck.

Wire and assemble the lamp. Prepare the cord and wire the socket the same way you would with a standard socket, outlined in Step 2 and Step 3. Screw the socket onto the nipple (attaching the lamp harp first, if necessary), add a lightbulb and shade, plug it in, and voila! One fully functioning glass bottle lamp at your service.

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