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Tools & Supplies: Glue and Adhesives
Talk about sticky stuff.
Hosted by Matt Leese
Paints, Solvents, Glues, Combustibles Hazards
JPTRR
Staff MemberManaging Editor
RAILROAD MODELING
#051
_VISITCOMMUNITY
Tennessee, United States
Joined: December 21, 2002
KitMaker: 7,745 posts
AeroScale: 3,164 posts
Posted: Thursday, June 12, 2008 - 04:38 PM UTC
The following was posted by a master of sciences in chemical engineering on another model site on April 26, 2004.
SOLVENTS:
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Alcohols: ethanol
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Trivial names "booze" and "hooch". Usually used denatured (rendered
impossible to drink). Used on diluting acrylic paint. Also used as brush
cleaner and on creating washes off acrylic paints with water.
Health hazards: Causes nausea, dizziness and intoxication (drunkenness) if
inhaled or (God forbid!) drunk. Substances used on denaturizing can cause
long-term ill effects. If inhaled, can cause headache and symptoms of
hangover due to rapid metabolism into acetic acid.
Alcohols: methanol
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Trivial names "wood alcohol" and "rubbing alcohol". Can be used as ethanol
as solvent, but IMO to be avoided at any cost. Too risky.
Health hazards: Extremely poisonous, amounts less than 10 g (roughly 1/3
liquid oz) can prove fatal. Lesser amounts can cause acidosis and
blindness. To be avoided at any cost. Too risky.
Methanol will burn on slightly greenish flame. If you have strange
substance which has a tint of green on its flame, it most likely is
methanol.
Alcohols: isopropanol
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Trivial names: IPA. Do not confuse with India Pale Ale, which bears the
same abbreviation.
Used: Diluting acrylics and other water-soluble paints. Especially good for
Tamiya acrylics. Usually used as car windshield washing fluid.
Health hazards: Nauseating, can cause headache. If inhaled, causes
hangover-like symptoms.
Aliphatic hydrocarbons: non-cyclic compounds
----------------------------------------
Trivial names: mineral turpentine, airbrush solvent and white spirit.
Used: Diluting alkyd paints (enamels). Used also as airbrush solvent for
enamels. Not usable for acrylics or water-soluble paints, which may get
flaky. Used also on creating washes off enamels and as brush and airbrush
cleaner.
Health hazards: They have mild odor, but can cause dizziness and nausea.
May cause neural damage in long term use.
Aliphatic hydrocarbons: cyclic
------------------------------
Trivial names: pinene, turpentine
Used: like non-cyclic stuff. Not as good as solvents, have strong odor and
evaporate easier.
Health hazards: Strong smell, cause dizziness and nausea. As aliphatic
hydrocarbons, but stronger. May cause strong allergic reactions.
Aromatic hydrocarbons
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Trivial names: thinner, toluene, xylene, benzene
Used: As a very strong solvent for enamels and two-component paints.
Solvent for uncured epoxy, polyurethane and polyester resin. Will attack
polystyrene and can be used as glue.
Health hazards: As name implies, these guys STINK. The aromatic
hydrocarbons contain one or more benzene rings, which make them potential
carcinogens and teratogenesis. Cause dizziness, headache and stupor. Used by
teenagers as inhaled drugs. While extremely efficient as enamel solvents,
these are a real health hazard. Long time use may cause neural damage and
personality changes. Allergic reactions on aromatics may prove fatal. Use
gas mask or breathing protector while dealing with aromatics.
Chlorinated hydrocarbons
------------------------
Trivial names: chloroform, *chloroethane, *chloromethane (* equals mono,
di, tri or tetra).
Used: Like aliphatic hydrocarbons, but contain one or more chlorine atoms,
which improve their diluent properties. Will attack polystyrene and can be
used as liquid glue
Health hazards: Cause drowsiness and are known carcinogens. Do not use
unless you have a fume cupboard.
GLUES:
======
Tube glue
---------
Contains aromatic solvents and chlorinated hydrocarbons and jellifying
agents. Will clutter plastic and serious modelers avoid this stuff.
Liquid glue, commercial
-----------------------
Usually a mixture of long chain chlorinated hydrocarbons and esters. May
cause mustard oil as a warning agent. To be used with good ventilation. See
above the warnings on chlorinated hydrocarbons and aromatic solvents.
Ketones, acetone
----------------
Used as liquid glue. Extremely swiftly evaporating, good for seams which
require swift drying.
Health hazards: Stinks, noxious when inhaled, causes nausea and headache.
May cause allergic reactions.
Ketones, n-butanone
-------------------
Trivial names: MEK, methyl ethyl ketone, ethyl methyl ketone. Commonly used
as polystyrene glue since the mid-seventies. Evaporates swiftly, has strong
odor.
Health hazards: Stinks, causes headache and can cause extremely strong
allergic reactions (intubation required!) Carcinogenic properties. While
well known as liquid glue, not healthy.
Esters
------
Trivial names: ethyl acetate
Healthh hazards: A healthier alternative for MEK as a liquid glue. Stinks
less and does not cause headache. Can cause dizziness. Not toxic, but can
cause drowsiness.
Alphacyanoacrylate
------------------
Trivial names: super glue, zap glue, magic bonder
Healthh hazard: Although have ominous name (molecule contains a cyano
group), these guys are not toxic. On the other hand, they originally were
developed for surgical purposes. Will glue skin in a split second. Do not
cut or tear any skin accidentally glued, but instead use water, soap and a
lot of patience to dissolve the glue off.
Some brands will react violently on acrylic fibers and cause burns if
wearing such clothes. I managed to trash one pair of cycling shorts that
way.
One trick known by the airplane modelers is "Puff the Magic Soda". Baking
powder sprinkled on a super-glue will cause it polymerizing immediately,
making up an extremely hard and durable seam. This can be used as putty,
but it dries rock hard and is tedious to sand.
PAINTS:
=======
a) Chemically drying: enamels, alkyds and two-component paints
Healthh hazards: Contain organic solvents (see above) and pigments.
Airbrushing only on a well-ventilated area. You know when you have
airbrushed too long if your nostrils get sticky. Inhaled pigments can cause
lung irritation.
b) Physically drying: acrylics
Healthh hazards: Usually diluted by either alcohols or water. Less hazardous
than enamels, but they still contain pigments as well.
c) Emulsions: any water based enamels
Healthh hazards: Like the physically drying paints sans aromatic solvents.
The emulsifying agents can be mildly carcinogenic.
Oil colours
-----------
Trivial name: oil, varnish. Based on vegetable oils, like linseed oil.
Usually natural products. Not widely used on modelmaking.
Healthh hazards: Self-ignition. Linseed oil contains lot of unsaturated
double and triple bonds, which react with each other and cause the curing
of the varnish. If exposed on combustible substance (such as fabric or
paper) and if crumpled tight, the heat may rise enough to lit the material
up and cause fire.
DECAL SETTING SOLUTIONS
=======================
These stuffs contain carboxylic acids, mainly acetic, propionic and butyric
acids. They have pungent or rancid odor, and may cause irritation on skin.
They are not dangerous per se, but exposure should be avoided. As decal
film is cellulose acetate, the stuff softens the film and enables any air
escape under the decal film.
Healthh hazards: Can cause irritation and allergic reactions.

JPTRR
Staff MemberManaging Editor
RAILROAD MODELING
#051
_VISITCOMMUNITY
Tennessee, United States
Joined: December 21, 2002
KitMaker: 7,745 posts
AeroScale: 3,164 posts
Posted: Friday, February 06, 2009 - 07:39 PM UTC
Here's a bunch of info I have on MEK from discussions years ago:


Quoted Text

Many things, correct and incorrect have been stated on this list about MEK. Lets not go by memory (which may be affected by MEK) and instead go to an authoritative source, a Material Safety Data Sheet. There are various sources available on the web, an easy one is:http://www.jtbaker.com/msds/m4628.htm Relevant portions include: DANGER! EXTREMELY FLAMMABLE LIQUID AND VAPOR. VAPOR MAY CAUSE FLASH FIRE. HARMFUL OR FATAL IF SWALLOWED. HARMFUL IF INHALED OR ABSORBED THROUGH SKIN. AFFECTS CENTRAL NERVOUS SYSTEM. CAUSES IRRITATION TO SKIN, EYES AND RESPIRATORY TRACT.
Health Rating: 2 - Moderate
Flammability Rating: 4 - Extreme (Flammable)
Reactivity Rating: 2 - Moderate
Contact Rating: 2 - Moderate
Lab Protective Equip: GOGGLES; LAB COAT; VENT HOOD; PROPER GLOVES; CLASS B EXTINGUISHER
Potential Health Effects
Inhalation: Causes irritation to the nose and throat. Concentrations above the TLV may cause headache, dizziness, nausea, shortness of breath, and vomiting. Higher concentrations may cause central nervous system depression and unconsciousness. Skin Contact: Causes irritation to skin. Symptoms include redness, itching, and pain. May be absorbed through the skin with possible systemic effects. Eye Contact: Vapors are irritating to the eyes. Splashes can produce painful irritation and eye damage. Farther down one will find that MEK is not now recognized nor anticipated to be a carcinogen. However, it has shown reproductive teratogenic effects in laboratory animals so keep an eye on you kids.... Bottom line - avoid if possible, protect yourself if you feel you must use it.



I forwarded the above information to an MD, and here is the reply (NOTE: the MD references comments made above, that I edited out years ago) :


Quoted Text

1) Custer's opinion that most teratogens affect only women is completely wrong.
2) Where did he get the statistic that 10 years is the required time to "metabolize anything in the body away"? Does the word mutation mean anything to him?
3) The "eggs" in the ovaries begin as oocytes in the primordial follicles, of which approximately 400,000 are present at birth, i.e, well before puberty. Oocyte maturation is then arrested at the time of birth, until follicular maturation prior to ovulation.
4) The suggestion that males have a protective advantage because they continuously produce sperm is wrong and dangerous. If the latest "crop" of sperm is affected by a teratogen (including alcohol) and that sperm is used to fertilize the egg, the embryo may demonstrate defects related to the damaged sperm. Many defects are due to teratogenic effects on the embryo and fetus and occur after conception, such as those due to thalidomide or radiation. Different teratogens affect the fetus at different stages of development; some that may have devastating effects in the first trimester may have no effect in the third trimester. This is dependent on the particular teratogen, which organ system it affects, how it affects that organ system and when that organ system is undergoing development.
5) What is Custer's definition of small amounts of exposure over time? What does he consider small and how does he measure this? How certain is he that these small amounts of exposure will have no effect and on what evidence does he base this? Fred, If you want detailed accurate information concerning teratogenesis and your own possible risks, get it from a physician who practices reproductive medicine. If you are concerned about possible hereditary conditions, ask the reproductive medicine physician to refer you to a geneticist. This sort of information should be as specific as possible to the individual(s) involved, and detailed exposure, medical and family histories are essential. An opinion from a lay person is dangerous...