Talk:Miniature relays

IIRC, the failure mechanism is that heating makes the coil outgas, and with no air vent, it condenses on the contacts when the relay cools off. Sometimes you can restore operation by exercising the relay with a square wave. Caution is advised since too much hammering will wear away the precious-metal plating on the contacts, leading to corrosion.

The case is also Delrin. Bruce Keefer told me it "burns with a beautiful blue flame", which the safety folks just loved.