On Wednesday, August 17, 2016 at 9:30:34 AM UTC-4, Ed Pawlowski wrote:
On 8/17/2016 8:10 AM, TimR wrote:
On Tuesday, August 16, 2016 at 11:52:56 PM UTC-4, wrote:
I don't understand how a corroded socket would lead to premature bulb failure. The only possible effect that I can think of due to socket corrosion is reduced heat transfer from the bulb to the material surrounding the socket. That is a negligible amount compared to the total heat radiation from the bulb.

Because you put more force on the base when screwing it in.


Please explain how a tad more force on the base makes the tungsten
element burn out faster. Not that I doubt you but I don't see the
correlation.

The connection of the aluminum base to the glass is marginal. Any extra force twisting it deforms it enough to leak air in which fries the element eventually. Even a little bit is bad.

I have no evidence for this. It's what I've been told, and it may or may not be true. There does seem to be some experience with bulbs burning out faster when people screw them in tighter, hence the recommendation to screw them in until they just light, then only an additional 1/8th turn. That's for incandescents, CFLs or LEDs might need a different torque.