LED Bulb: Mechanical FAIL

Replacing the second torchiere lamp shade required unscrewing its 100 W equivalent LED bulb, which required far too many turns and eventually felt sufficiently wrong to reveal the problem:

LED Bulb - unscrewed base
LED Bulb – unscrewed base

The entire metal base shell unscrewed from the plastic housing and twisted off the lead from what looks like a PTC fuse in series with the center contact; the cute little pigtail effect suggests I’ve wrecked the epoxy-to-wire seal.

It had a five year warranty which, alas, expired three years ago. This style of bulb has fallen out of favor, so I may as well get some Quality Shop Time out of it.

I don’t know how the factory machinery attached the lead to the contact button, but I’m going to go primal on it with some solder. The trick will be soldering it after assembly, so the first step is to drill through the middle of the button.

Grab it nose-down in the Sherline’s three-jaw chuck, flip it over, grab the chuck in the drill press vise, line it up, center-drill the button, then drill right through that sucker:

LED Bulb - base drilling setup
LED Bulb – base drilling setup

Of course, the contact came loose from the base, because I pretty much drilled right through the rivet flange holding it in place:

LED Bulb - removed center contact
LED Bulb – removed center contact

Nothing a dab of epoxy can’t fix, though. I scuffed up the outside of the contact to remove the nickel (?) plating and expose the underlying brass to improve its solderability.

After the epoxy cured, align wire with hole, screw the base onto the lamp shell, and it’s ready for soldering:

LED Bulb - base ready for solder
LED Bulb – base ready for solder

The hole is way too large for the wire, but I wasn’t about to wreck a tiny drill on what might have been a weld nugget. In any event, the bigger the blob, the better the job:

LED Bulb - soldered base
LED Bulb – soldered base

Just like light bulb bases used to look, back in the day.

With a bit of luck, it’ll sit in that socket for another seven years.

It could happen, ya never know.

4 thoughts on “LED Bulb: Mechanical FAIL

    1. There’s at least one high-power LED jockey out there in readerland keeping me honest.

  1. I had that little metal button just fall off of brand new bulbs from the Homeless Despot. I went back to replace them and checked the boxes before taking them and found that roughly 50% of the bulbs had the flaw. I tried to tell someone and got blown off.

    1. Sort of like hard drive production, where any one of us may see a single failure and bulk buyers can get an entire shipping container of duds.

      Folks on the sales floor definitely aren’t empowered to make meaningful stock changes …

Comments are closed.