On 11/26/2011 11:45 AM, Bill Gill wrote:
....

According to Wired Magazine a couple of years ago one
of the main ingredients of WD-40 is mineral oil, a
lubricant. There are other things to take care of
water and as a dispersant.
....

That's not quite correct according to the MSDS. The primary ingredient
is Stoddard solvent (70% or so, precise values not given) which is
similar to, but a lighter fraction than kerosene.

The second ingredient listed is a (very) light oil 15% or so that is the
same CAS as Fisher Scientific pump oil

http://fscimage.fishersci.com/msds/11406.htm

So, it's a case of "all of the above" -- it has some lubricating
properties but wasn't developed for the primary purpose of lubrication.

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