Yet another poo-quality component from Jaycar.

[GK]

I've had a bad run with these used for mains switching:

http://www.jaycar.com.au/Electromechanical-Components/Switches/Toggle/SPST-Standard-Toggle-Switch/p/ST0570

Bad as in the toggle lever suddenly having fractional-ohm resistance between itself and one of the terminals at the back. In both instances so far upon flicking the switch ON the active line fuse vaporized before the RCD tripped. This is in metallic, earthed-chassis equipment. Earth is at neutral potential here (M.E.N. system), so the switch failing incurred a direct active to neutral short. I didn't get a noticeable shock.

I'd recommend not to use these cheap-arse switches for mains switching (despite the 250VAC rating) in plastic-cased equipment.

Tangentially related; I have a small collection of Radio Television Experimenter booklets and the attached is typical of nearly all mains-powered designs in that publication - metal chassis, twin flex mains lead and no earth. And this was back in the days before RCDs/ELCBs. I guess mains-rated switches were made to a better quality standard in those days.

[SeanB]

No, those switches have gotten poor over the years. The older versions used thicker casing parts, and thicker brass for the terminals and the internal construction, along with much beefier internal insulation. Take it apart, it is only 2 small screws, and you will find the internal small plastic carrier that is supposed to provide all the insulation. Old ones are pretty much filling the entire inside, not the little pip of plastic there is there now, and the metal was a lot thicker, with that lovely unsolderable chrome plate you had to scrape off to solder.

[GK]

They look like screw heads in the photo but they are actually rivets; inspection on any unit would be destructive. The duds have already gone out with the trash.