CA fumes

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Paul Downes

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May 19, 2004
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Westphalia, Mi, USA.
I started using the CA finish on my pens and noticed that it gives off rather nasty fumes as it is curing. The fumes really make your eyes burn. I first coat with BLO and then put a coat of CA with a Few drops of BLO on a paper towel. Then 3 coats of CA with wax paper, followed by Hut waxes and then crystal coat. While I really like the gloss finish I never saw any mention of the fumes. I have been allowing a breeze to blow through the shop to limit exposure. I wonder what the MSDS says about these fumes?
 
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leenollie

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Apr 19, 2004
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San Antonio, Texas, USA.
Hi Paul,

I'm afraid fumes are an "occupational hazard" when using CA as a finish. I have heard that they make a "fumeless" CA, but I have not been able to find it locally. I don't know about the physical hazards of the fumes, but as a good rule-of-thumb, just make sure there is a good ventilation flow when finishing with CA. Also, I found that with using the slow-dry CA, the fumes are not nearly as bad when finishing, especially when I put the BLO on immediately after applying the CA. Hope this helps.

Lee Biggers
The ever curious pen turner [:)]
 

timdaleiden

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Mar 17, 2004
Messages
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Location
Wausau, WI, USA.
I hope I don't get in trouble for copying, and pasting this from the Yahoo archives. It is quite lengthy, but worth the time.

"Message 1776
From: Steven D. Russell
Date: 1/19/2001 1:51:00 PM
Subject: Re: [penturners] CA glue toxicity?

Hello Rich,
I recently posted some information on the rec.crafts.woodturning
newsgroup that is on point. I have copied the two posts below. Apologies
to the rest of the group is this is old school.
Cyanoacrylates, A Brief Overview:
Monofunctional 2-cyanoacrylates were first patented in 1949, but the
first viable production process did not evolve until 1954. In the early
1950's, scientists at Eastman Kodak were working on thermal
polymerization and discovered the rapid room-temperature cure and
excellent adhesion properties of 2-cyanoacrylates, quite by accident.
While working on a freshly prepared monomer, the scientists discovered
that the glass prisms of the refractometer has become tightly bonded.
Extensive work thereafter, found that many different types of substrates
bonded in the same manner. Subsequently in 1958, Eastman 910 debuted,
the
first in a large family of 2-cyanoacrylate ester adhesives.
2-cyanoacrylates polymers spontaneously form (via an anionic/radical
mechanisms) when their liquid precursors, or monomers are placed between
two closely fitting surfaces. The great utility of these adhesives
arises from the electron-withdrawing character of the groups adjacent to
the polymerizable double bond.
The high reactivity (cure rate) and their polar nature, enables the
polymers to adhere quite tenaciously to a wide variety of substrates.
Low humidity and/or acidic groups on the substrate surface will slow or
inhibit the cure reaction. To extend the usable shelf life, free-radical
stabilizers such as quinones or hindered phenols are used.
Methyl, Ethyl, Butyl, Allyl and Methoxyethyl esters are available with
various setting characteristics and rheological properties. However, the
Methyl and Ethyl esters dominate the commercial industrial market. The
vinyl structure of 2-cyanoacrylates makes them prone to spontaneous
polymerization. The chain propagation can be initiated by ionic or
radical mechanisms.
The rate of polymerization depends on temperature, humidity, light and
the presence of accelerators, like peroxides or bases. In addition to
polymerization, 2-cyanoacrylates undergo reactions typical of vinyl
compounds, such as addition.
2-cyanoacrylates can be manufactured by many different methods. The base
monomers are too thin for convenient use, so thickeners, stabilizers or
property-modifying additives may be added. The viscosity's are available
from wicking grades (water thin) to thixotropic gels that range from
20,000 to 50,000 mPa*s for large gaps.
The acrid odour of 2-cyanoacrylates, can be effectively mitigated by the
substitution of an alkoxyalkyl ester side chain, for the normal alkyl
group. Products so modified, are practically odour free, but are
slightly less effective as adhesives.
The basic method to manufacture 2-cyanoacrylate esters involves
preparation via the Knoevenagel condensation reaction (the corresponding
alkyl cyanoacetate reacts with formaldehyde in the presence of a basic
catalyst, to form a low molecular weight polymer). The resulting polymer
slurry is acidified and the water is removed.
The polymer is then cracked and redistilled at high temperatures onto a
suitable stabilizer combination to prevent repolymerization. Protonic or
Lewis acids are typically used in combination with small amounts of a
free-radical stabilizer.
Although the methods and processes have continually changed and evolved
over the years, this is the standard method to manufacture these esters.
One recent and significant advancement in the manufacturing process is a
continuous process where the condensation is carried out in an extruder.
By-products are then removed in a degassing zone and the molten polymer
(mixed with stabilizers), is cracked to yield a raw monomer.
Recent advances have lead to flexible 2-cyanoacrylate formulas, which
remain somewhat flexible when cured. These types of esters are
particularly useful to turners when bonding dissimilar materials like
stone/metal and wood. The dissimilar expansion and contraction rates of
these materials, can cause subsequent failure of the bond when using
traditional cyanoacrylates that feature non-flexible, or brittle bonds.
Health concerns when using CA:
A few recent threads have mentioned CA glue and its sharp, pungent
fumes/odour. These fumes are not to be taken lightly! 2-Cyanoacrylate
esters are lacrimators, even at low concentrations. These esters are
irritating to the nose, throat and lungs in concentrations as low as 3
ppm. Eye irritation is typically observed at 5 ppm, or higher.
Adequate breathing protection (this means a proper respirator, outfitted
with an organic vapour cartridge) is essential when using these
adhesives. Additionally, you should not bend over the area, whilst you
are applying the CA to the area. If you do not wear a respirator,
adequate and thorough ventilation is ESSENTIAL. Some CA's have may cause
health conditions such as Allergic Contact Dermatitis or Occupational
Asthma.
We are all aware how well CA will bond skin tissues. It's best to wear
protection on your hands when using these products, as well as eye
protection if you do not wear a full face respirator. Contact with
liquid CA through the clothing will produce a rapid exotherm, which may
cause severe burns and scaring. Contact with the liquid CA in the eyes,
can cause rapid exothermic polymerization, leading to severe eye injury,
or corneal lesions. You should NEVER use CA without proper eye
protection.
Many turners use CA's to fill small inclusions, or fissures in turned
items either mixed with a filler, or by itself. If you switch on the
lathe before complete polymerization has occurred, uncured CA may fly
into your eyes, face, skin or clothing.
Cured 2-Cyanoacrylate ester polymers are relatively non-toxic. In lab
tests, oral doses of 6400 mg/kg failed to kill laboratory rats. Guinea
pigs exhibited mild skin irritation, but there was no evidence to
suggest sensitization, or absorption through the skin.
There is a fire hazard with liquid and cured CA esters, because both
forms will support combustion. You should not use these adhesives near
sparks, open flames, areas of acute fire hazard or heat sources. Highly
exothermic polymerization can occur from the direct addition of various
catalytic substances like water, alcohol's, amines, ammonia, caustics,
or surface activator solutions.
Take a bit of extra time to insure your protection protocols are
up-to-date when using substances that are hazardous. A few seconds of
extra time spent protecting yourself, is time we can ALL afford to
spend. If you would like to learn more about CA adhesives, look for my
upcoming comprehensive article in "Woodturning" (British) magazine. Take
care and be safe. :)
Copies of postings ends.
If you have any questions, please do not hesitate to contact me. Take
care and all the best to you and yours!
--
Letting the chips fly...
Steven D. Russell
Eurowood Werks Woodturning Studio
The Woodlands, Texas"


I built something to help me with these fumes, as well as other concerns, and it is currently available as a pdf article on the front page here as "Dust collector."
 

Daniel

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Joined
Jan 1, 2004
Messages
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Location
Reno, NV, USA.
Yes the fumes are hazardous, I know of three suggestions. Good ventelation which has already been suggested, a mask that will stop fumes. I was lucky and got one at work when we had to clean sidewalks with hydrocloric acid. talk about fumes, that stuff makes CA seem like roses. and odorless CA which also has been mentioned (but expensive)
you can get the odorless for $6.01 for 1oz. or $10.54 for 2oz. at the CA Bulk Buy
http://yourdonspens.com/CA_Glue_Page.html
 

dw

Member
Joined
Feb 10, 2004
Messages
78
Location
Redmond, OR, USA.
Couple of questions come to mind in that regard...

Is the hazard really reduced with odorless or is it that we just can't detect it?

Is it possible to do a decent CA finish with "medium" CA alone?

thanks in advance
 

Daniel

Member
Joined
Jan 1, 2004
Messages
5,921
Location
Reno, NV, USA.
DW
I have doen a decent CA finish with thin alone. in fact most of my CA finishes where doen with thin CA. It is a pain adn takes allot of care, adn often sanding off the finish and starting over. but I would say yes you can get a good finish with Medium.

the odorless CA is used by many that have either developed problems with CA fumes or started off outright allergic to them. or having soem simular reaction. it fixes the problem for them. I believe the odorless has a different carrier, or base to it. but am not sure.
 
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