In article ,
"Michael Koblic" wrote:

"Joe AutoDrill" wrote in message
...
"Rick Samuel" wrote in message
...
Acetone will leave a residue, Iso alcohol will not.

CLIP

No kidding! For years, I thought acetone left no "evidence" of use...
Then I tried to prep a window that was tinted on the opposite side for a
decal and found this really annoying oily substance all over the window
afterwards.

Now, I wonder why that is. Basic chemistry tells us that acetone should
evaporate completely leaving no residue. Could it be that it is not an
acetone residue at all but residue of such oils and fat that were there
before acetone was applied, dissolved in acetone and the acetone just
evaporated too quickly? The speed of acetone evaporation is noticeable, just
feel the cooling of the area (or the rag) where the acetone was applied.

As others have pointed out, ordinary acetone usually comes with oil
already included.

However, a trick I have used over the years is to mix acetone and 91%
isopropyl alcohol about 50-50 by volume.

The effect can be dramatic: Get three containers, one with acetone, one
with alcohol, the third empty. Try cleaning a surface with a paper
towel dipped in the acetone - smears stuff around but doesn't really
remove the stuff from the surface. Then try cleaning a surface with a
different paper towel dipped in the alcohol - no effect. Pour the
alcohol and acetone into the third cup, mixing them thoroughly. With
yet another paper towel, try cleaning the surface -- the stuff is
removed immediately.

Why does this work? The acetone dissolves stuff that alcohol cannot
touch, and then evaporates, leaving the stuff as a fine dust dispersed
in the alcohol. Following up with pure alcohol should get the residual
oil as well.

Joe Gwinn