[Antennas] RE: Glass Cleaners and Adhesives
Barry L. Ornitz
[email protected]
Sun, 28 Apr 2002 20:24:51 -0400
Chris Bonde, VE7HCB, wrote:
>Eventho acetone is available in finger nail polish and
>airplane glue, be very careful with it. The kids sniffed
>these common products, and after awhile had bad health.
>Pure acetone may be even more dangerous. Some people may
>even smell of acetone, a usual indication of bad health,
>as acetone like products indicate that the body is not
>completely utilizing certain chemicals.
As a PhD chemical/electrical engineer, I have worked
extensively with acetone [one of my former employers used
to lose about 80,000 pounds per day of acetone to the
atmosphere due to evaporation in one of their processes].
I am quite familiar with its hazards.
Bob, K2MY, is absolutely correct about it not leaving a
residue on glass if it is pure. As he notes, it is a
excellent solvent for organic (but not silicone) greases
and oils.
Fingernail polish remover is acetone with water and
fragrance added. The water lessens its ability to dissolve
grease, however. To the best of my knowledge, acetone has
not been used in model airplane glues for many years. Most
modern polystyrene cements these days use methyl-ethyl
ketone or methyl-isobutyl ketone (which are far more toxic
than acetone). Acetone was used back in the days of fabric
covered aircraft wings as the solvent for airplane "dope".
I am not sure of the origin of the word, but all solutions
of cellulose esters (like cellulose nitrate [celluloid] or
cellulose acetate) are called dopes.
Acetone will certainly give one a "buzz" if inhaled in
excess. However, it is far less toxic than most other
solvents. I would not want to do it, but you could drink
about a ounce of acetone without being killed. You might ]
wish you were dead from the hangover, however. As a
rough measure of its toxicity, it is generally considered
slightly less toxic than isopropanol (the pure form of
rubbing alcohol). "Huffing," as the stupid kids call
inhaling solvents, is plain dangerous with any solvent.
Liver and kidney damage generally results along with
neurological problems.
For cleaning and degreasing old gear, I often suggest
acetone because of its relatively low toxicity. It is a
polar solvent, as is isopropanol, so it is usually better
used after a first wash with a solvent such as VM&P naphtha
which is non-polar. This is "Varnish Makers and Painters"
naphtha and it is a slightly more refined version of
materials used for paint thinners. Acetone and naphtha can
both be bought in most major paint stores.
Acetone and naphtha, both having low flash points, are
extremely flammable. Thus it is best to work outdoors with
them, well away from sparks and flames. Wearing rubber
gloves is strongly suggested. The Buna-N nitrile gloves
are best.
Acetone on the breath is something I am personally familiar
with. It occurs in diabetics when their blood glucose
levels are excessive and is due to improper metabolism of
the glucose.
Unfortunately I have been extremely busy lately and not had
time to do more than just scan this list. When I have
time, I plan to write about plasticizers in vinyl that came
up earlier when someone wrote about contaminating and non-
contaminating coaxial cable. I also plan to write about
stainless solders, aluminum solders, and electrolytic
corrosion.
The issue of plasticizers, however, is appropriate here.
If you park you car with the windows closed in the hot sun,
you will soon find your windows fogged with an oily film.
This is the plasticizer which has evaporated from the
auto's interior vinyl. The vinyl left behind eventually
shrinks and gets brittle. The film is difficult to clean
with ordinary window cleaners which are mainly denatured
alcohol and detergents. I have found that wiping the
windows with naphtha first, followed by acetone next will
remove this film quite well. Finish with conventional
window cleaner. This can be "vinegar" based or alcohol
based. And by the way, pure acetic acid (industrial
vinegar) will evaporate cleanly too. It does a better job
of removing inorganic spots on glass left by calcium-
containing hard water. Any residual plasticizer left on
the glass will impair the use of adhesives.
When cleaning plastics with virtually any cleaner, it is
best to test the cleaner in an inconspicuous spot first.
Acetone, alcohols, glycol ethers (bathroom cleaners), etc.
can soften and attack many plastics. So test first.
Dr. Barry L. Ornitz WA4VZQ [email protected]