Repair Tips

Some tricks and tips to keep in mind are universal across all repairs. Instead of having search through the blog or repeat them in each post, this page will have a brief list of the tips.

Removing the Socket Shell from Cap

Most every metal socket shell is marked with "Press" close to the key shaft or the push thru knob. Using a flat head screw driver at this point, apply pressure between the cap and shell of the socket. The socket will click loose on that side then rock the shell loose from the cap. Most repairs allow us to reuse the socket cap and shell so do you not want to warp, cut, bend, or break the shell or cap.

removing the socket shell from the socket cap
Plastic or Bakelite (phenolic) sockets usually screw loose. Some heavy metal sockets have a screw coupling holding the cap and shell together.

UL Knot

The UL knot is easy to mast and should be used in every lamp socket. This knot holds the cord in the socket with out putting stress on connections to the socket terminals. 

 Some sockets have a quick connect base. I do not recommend these because they seem to have a high failure rate and do not work well in repairs (the plastic clips break).

It is common to find a lamp wired with no UL Knot. Not to worry: you can put one in when you make the repair.

Other Knots

It is a good idea to include other knots in lamps to protect the cord from getting pulled from the lamp. Often we will put a knot in the base of  the lamp or in a non-molded plug. If someone pulls the lamp or the cord, the stress and pressure is on the knot. 

This plug should have a knot in the plug so the cord gets held inplace and any stress on the cord does not transfer to the terminals in the plug.

Polarized Plugs

Modern plugs are polarized for a common and hot line. Modern house outlets have matching polarized terminals (one large and one small). You can find more technical information about polarization in other places, but here I will always recommend using polarized plugs and wiring sockets to match the right current. 

These plugs clearly show the difference between a polarized plug and an older plug.

lamp cord comparison

Polarized Sockets and Wires

Modern lamp cords and wires have identifying hot and neutral marking. Like the plug, this directs the flow of electricity through the lamp and increases the safety of the components. Cord sets with parallel cords and a molded plug have one ribbed wire and one smooth wire to help guide the installation to the lamp socket. Modern lamp socket interiors have a brass (gold) screw and a nickle (silver) screw. The ribbed wire should connect the silver screw and the smooth wire to the brass screw.

In this photo you can see the ribs on the wire in the foreground.

Wire Tipping and Direction

It is important to reduce the wire fray in a socket and keep everything tidy. Two important tips for this is to make sure you bend the wires in a clockwise position around the terminal screws and solder tip the wires. In the photo below you can see the wires are wrapped around the screw in a clockwise direction. When the screw is tightened, the cord is pulled into place and not backed out of the screw. 
lamp socket wired

Adding a dab of solder to the wire will help with reducing wire fray.

lamp cord close up

Lamp Socket Insulators

Every lamp socket new and old has a cardboard insulator to keep the wires away from the metal socket cap and shell. Over time these insulators deteriorate and break down. This creates a very dangerous situation. You should plan to replace any insulator that is brittle. Insulators will last years and are inexpensive so they should be replaced. In the photo below you can see three insulators. The one on the left is new and the other two need to be replaced.

paper lamp socket insulator


Many lamps have movable parts. Swivels allow you to adjust the angle of light or the direction of the lamp without moving or adjusting the lamp base. While swivels come in different sizes and styles they all have one thing in common: they take the lamp cord along for the ride. While lamp cords are generally flexible, if they are twisted or bound you could have serious issues. Swivels, like clusters, generally open for threading the lamp cord.

Pole Lamp Swivel

Butterfly Knob Swivel
Some arms have a swivel feature. As we witnessed in a recent repair, these swivels can be very tricky to thread a lamp cord. Remember to removed the caps at the joints, takes your time, and do not twist the wire in the arm. 

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