By the by
I made a study of the evaporative / gumming characteristics of WD-40
it doesnt do either to any significant degree.
This all started when some one said that WD-40
EVAPORATES off a sharpening stone and is OK to use as an oil stone oil. I knew that mineral oil would not
evaporate and suspected the WD would not as well. I didn't like the sound of using WD on an oil stone because I expected it would
gum up the stone though. The person who said it would evaporate off the stone was all higher educationed out and so thought they were scientifically correct. See hydrocarbons blah blah blah.
Some times seat of the pants in the shop experience can contribute to science. This is oneO those times.
To see if ANY of the oils would EVAPORATE . . .
(none of them actually left the glass like water would EVAPORATE.)
I put puddles and thinnish smears of several oils on a sheet of glass. Most of the oils were woodworking finishes and un catalyzed drying oils. Just to have something to watch while the WD did nothing. They all solidified to a plastic state over weeks and months. EXCEPT as I suspected the WD. [PS: and the Camellia didn't solidify ] It is about a year later and the WD-40 is still just like when I put it on the glass except for all the dust in it. Check it out. Do the experiment for your self on glass. Keep it dust free until you are satisfied. I just never got around to doing anything with my sheet of glass.
Notice the progression over time of the drying oils (woodworking finishes and fine art oil painting oils) gelling and eventually turning to plastic literally . . . while the WD-40 remains fluid and for practical purposes unchanged.
Notice that, once again, using my finger I was able to smear through the still wet (non-evaporated) puddle and film as well. In spite of the abundant dust collected on the surface.
I still would not put it on an oil stone. For that matter I have no use for oil on a stone. Water on water stones and kerosene on an oil stone, thank you very much, on the very rare occasion when I have a blade that rusts so fast I want to use something other than water.
By the way I have now secured some espresso and am now feeling MUCH better.
PS: the "Cam" on the glass is Camellia oil to see if it gummed up. I strongly suspect this is just mineral oil with a fancy label because in the old days Camellia gummed up on me and this didn't.