Replacing a light switch

Not a metaphor, just a light switch that was getting unreliable:

Light switch
So here’s the switch, made about 45 years ago by the GE corporation. Let’s take it apart!
Light switch showing interior dust
Over long periods of time, dust in an old house works its way into everything, including electrical switches. The dust causes poor conduction in the switch contacts
Switch contacts arranged side by side
Here are the switch contacts, normally facing one another. But I’ve flipped one over so we can see them both.
Light switch contacts pitted by arcing
In extreme close-up, we can see that the result was an electric arc where the dust interfered with switch contact. Notice that the brass is discolored from heat, and some of the metal face of the contacts has been vaporized. Most interesting, one of the contacts, which are 3 mm in diameter, got so hot it developed a circular crack around the point of poor contact.
This is normal switch wear. It only takes about five minutes to replace a switch though and it’s a couple bucks. So no biggie.
Switch contacts arranged for photography
I won’t lie, it took multiple attempts to get a passable photo of those 3mm contacts. In operation, the short contact is flipped so it is facing the long contact, which is moved by a molded cam on the switch lever itself.

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Older technology guy with photography and history background