On Thu, 08 Oct 2009 18:54:01 GMT, "The Medway Handyman"
had this to say:

Dave Osborne wrote:
PeterC wrote:

Out of interest, is there a thin spray lube that's OK for switches,
locks etc?

PTFE dry-film lubricating spray.

Contains tiny balls of PTFE (Teflon) suspended in volatile solvents.
The solvents evaporate leaving the PTFE as a dry-film lubricant.

Apart from generally being bad, WD40 has a tendency to get onto the
key and then stain your hands/clothes, so it's a bad idea for this reason
alone.

Then why do Yale reccommend WD40 in black & white? Arrrrghh!

I _think_ this has been answered previously. Hardware manufacturers
are increasingly desperate to sell you new kit, so they're hardly
likely to promote stuff designed to prolong the life of their existing
products. Since everybody has heard of WD-40, it sounds apposite for
them to 'recommend' it, so as to make their kit 'trendy'.

--
Frank Erskine