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Lamp Repairs

– How to Rewire, Switch Replacement & Underwriter’s Knot

Alright so today on Repairs101 I’ve got two lamps that need repairing and as luck would have it, they each have something different wrong with them.

Look under the hood of this piano lamp and the problem is obvious: the wrong kind of bulb has cooked the insulation on the power supply.

According to code

The cord has to be six feet long to be up to code so I got this eight footer at the hardware store. The neutral blade on the plug is oversized to prevent reversed polarization and the neutral strand of wire is textured with ribs to differentiate it from the “hot” lead.

The ribs are easy to detect by rubbing your finger across them. So get the wires loose first and then pull the socket out. I opened it to find the wires were soldered so I cut it free. Then I pulled the grapple grommet which holds the wire secure.

After that, just dismantle the stand and pull the wires out. I like to tape the end up to protect it from damage while I’m fishing it through the stand.

Transfomer x Anker GaNPrime Charger and Power Bank

I let my solder pen get good and hot before I melted out the old wires. The second wire was a bit stubborn so I added some flux paste as an accelerant. Flux core wire works too.


Now to make sure your lamp is polarized correctly attach the ribbed neutral wire to the silver coloured connection and the hot lead to the brass connector. You can put those heat shields back on now and close it up. These grapple grommets are best installed using a pair of pliers. Some glue stick on the base and… There you go. Just like Edison said.

This filthy old banker’s lamp’s problem is obvious. I’m just going to pull it out and compare it to a brand new one. You can hear the difference.

Underwriter’s knot

Here’s where you’d expect to see an underwriter’s knot. They’re easy enough to tie. But this grommet will prevent it from being pulled out. The next thing is to “fresh end” the wires. You want to strip five eighths of an inch of insulation and twist the strands clockwise and mount them neatly so that they go on clockwise. Again, remember: silver is common and gold is power. Lamp repairs: a metaphor. Amirite?

Alright thanks for watching and don’t forget to subscribe!

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