Explosion

When I was at my mum's at the weekend I was swapping a few inefficient incandescent and lots of horrible CFL bulbs for nice new LEDs.  Hopefully this will help with energy bills as well as improving the quality of light.

When I tried to do her reading lamp I found it was very wobbly and the (40+ year old) lampholder was cracked and in danger of exposing live contacts.  She's attached to the light, so I said I'd try to fix it.  I've glued some of the damaged fittings back together to get rid of the wobble, and today a new bulb holder arrived.  I fitted it, turned it on, and...

...BANG!

A bright flash (scorching the hair off my fingers), big bang, and puff of smoke.  All the sockets on the ground floor went off too.

CyclopsJnr (who was helping with the task) found my reaction to this hilarious.

I reset the breaker and took the blasted (literally!) thing apart again.  I assumed I must just have failed to properly tighten a wire (although I'm usually good at that sort of thing) but it quickly became apparent the wires were properly secured and the scorch marks came from inside the fitting, not where the wiring is.  Further investigation suggests that it had shipped with one of the internal screws rattling around inside, which shorted it out and was mostly destroyed (I only found fragments).

I have contacted the retailer for a replacement.