Replacement for Araldite AV1253

Robert Proctor <robert [at] whittenandproctor__com> writes

>We have been using Araldite AV1253 carvable epoxy for replicating
>missing frame ornaments but are concerned by the warning stating
>"this product contains chemicals known to the State of California to
>cause cancer". One product I have found through a quick Google
>search is Abatron WoodEpox which clams to be "Greenguard Certified".
>Can anyone recommend this or any other product as a substitute for
>Araldite?

I have been using Abatron for around 10 years and I really like it,
but I would not compare it to Araldite, as Abatron is a lightweight
putty, almost "foamlike", while Araldite if I'm not mistaken is a
viscous liquid. Abatron does not have the "quick stick" that most
traditional epoxy resins have, though once you mix it up and press
it against the substrate, if you let it sit while setting it will
usually bond very strongly to the substrate in around an hour.  As
far as your concerns about epoxies being safe, my understanding is
that most epoxies are more similar than different, and usually
differ mostly in the additives to the resins, which usually
constitute mainly thickeners to prevent them from running before
setting, and catalysts which accelerate the set.  Some epoxies
(think Hxtal) are exceedingly thin (less viscous than corn syrup)
and take a long time to set (a week), and unless you can contain
Hxtal it will run wherever it can.  I would assume whatever
California objects to in Araldite the same or a very similar
material is probably in Abatron.  While I love California, they
object to a *lot* of materials I don't usually worry much about as
long as they are handled properly.

I would think of Abatron as an alternative to Araldite, but not a
replacement.  One thing it has going for it is readily for sale in
my area; I have found it for sale at Ace hardware and at a local
house paint store. It was engineered as an architectural wood filler
for homes, windowsills, and the like and I think it is purchased by
homeowners and contractors for patching knot holes and etc.  You
might try a small lot of Abatron, I found a set of two 6 ounce tubs
this weekend for only $20.  What I like about Abatron is it is very
light but also quite rigid and tough, though still very easy to cut
and carver with a scalpel.  I think it is heavily bulked with glass
micro balloons in order to achieve these properties.  One
interesting feature is how it behaves when exposed to moisture
before it sets; I will often apply it to the substrate, but its
tackiness and thixotropic properties can make it difficult to
manipulate into exactly the shape you want, but if you wet one of
your gloves, is works the putty very smoothly, and you can get it to
conform to a void better, in addition to spreading it smoothly and
thinly.  One drawback it has is an expiration date; in about two
years it "expires" according to the manufacturer and while it will
still set at that point (perhaps not later) it sets faster and gives
you less control over shaping.  I have some other epoxy resin sets
that are very old but they are still fluid and still set well.  I
have some 10 year old Hxtal that sets well but is no longer
water-white.  I have some at least 15 year-old Abocure (a more
traditional epoxy resin, also made by Abatron) that still sets but
is/was always a dark brown color after setting.  I hope this is
helpful,

Tom Braun
Objects Conservator
Daniels Objects Conservation Laboratory
Minnesota Historical Society
345 Kellogg Boulevard West
St. Paul MN 55102-1906
USA
651-259-3382
Fax: 651-296-9961


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                  Conservation DistList Instance 26:19
                Distributed: Tuesday, September 25, 2012
                       Message Id: cdl-26-19-003
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