Today I was able to not spend about US$30.
In September 1986 I bought a work table for the new computer that I was using to complete the thesis for my master’s degree. Along with the table, I bought a nice lamp to go with everything else–an example of “one new thing requires several other new things.
The lamp recently started to intermittently go dark as well as not lighting up when the switch was turned on. A gentle tap of the lamp would return the lamp to normal so I ignored it for awhile.
Yesterday it annoyed me enough that I decided to see what I needed to do to fix the problem. Fortunately the lamp was old enough that it was fixable. Instead of glue, it was held together with screws, albeit screws that needed a strange 5 sided drive with a hole in the middle so that a regular “strange 5 sided drive” would not work. I dug deep, very deep, into my tool collection and found the correct tool, a tamper proof pentalobe Torx bit. For what it’s worth, I didn’t know the name of the tool until I read the box containing the tool bits.
Anyway, when I took the lamp apart, I found the problem. A wire going to the lamp socket had overheated and burned apart. The two ends of the wire were sometimes touching and sometimes not touching, which is why a gentle tap would make the light work.
I was both surprised and annoyed at my discovery.
The lamp uses a halogen bulbs which must operate above 250C degrees in order to work properly. I measured the temperature of my lamp’s socket and found it reached 290C degrees in about 2 minutes. The manufacturer used wire with an insulation with a maximum temperature rating of 60C degrees!
As the lamp was used, the plastic insulation overheated and eventually fell off the wire. It looks like the lamp designers knew this would be a problem because small channels were made in the lamp fixture to hold the wires physically apart so that even if the wire insulation was gone, the wires would not touch together and cause a short circuit. Eventually the wire itself was damaged by the heat and broke.
I replaced the burned wires with wires designed to directly connect to things as hot as 400C degrees. If the incorrect wire lasted 34 years, I guess the correct wire should last until my daughter needs to figure out what to do with the lamp.
The wire is normally very expensive but because I needed only two short pieces, I was able to buy some “scrap” wire too short for much else for US$5.
And that’s what I did to not spend US$30.