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Testing a New Alginate or FiberGel

E F/X Grade Alginate,

Fame or Shame

by David E. Parvin, A.L.I.

With so many alginates on the market, is there room for
another? Almost certainly not unless there is something that
definitely separates it from the rest. Ed McCormick of
ArtMolds is convinced that his new FiberGel E F/X Grade
alginate may just have what it takes and has filed for a patent.

A Little Background

During World War II, the U.S. Navy began using
alginate for dental impressions in place of agar which was
only available from Japan. Alginate quickly spread to the rest
of the dental profession. L(For a detailed history of alginate,
see "Alginate Life Casters' Gold" by Ed McCormick, "Art
Casting Journal" September 2001) The name of the first artist
to recognize alginate as an ideal material for life casting has
been lost to history but it is easy to imagine the scene. He or
she was probably a dentist who, when removing a cast of
some poor victim's incisors to molars, suddenly realized that Stretching a sample for strength

this alginate stuff just might be able to cast some more casting a face. The impressions of the inside of the ears can
interesting parts than teeth! tear loose. If the alginate is too hard, it can be difficult to
remove the mold from the subject or vise versa. Also, the
Life casting had begun. greater the likelihood of pulling out hair. Life casting is not
suppose to also be a bikini wax! Up until now, all alginate
The biggest problem with using dental alginates to cast shave been compromises. In other words, manufactures have
any part bigger than a mouth is that they set up too quickly. tried to make alginate as strong as possible without being too
Eventually, alginate became available that had setting times hard. The better brands have done this very well and there are
of 5 to 8 minutes which allowed for more elaborate castings. some excellent alginates available that serious life casters,
These were and are essentially dental alginates slowed down. myself included, have used for years with great results. But
Most of these alginates are still produced by dental firms as ArtMolds's Ed McCormick has a new approach. Ed believes
line extensions. And so it has gone up until now. ArtMolds that he has discovered a way to increase strength while
may be the only company that manufactures alginates maintaining an optimum softness by adding just the right
exclusively for life casting. amount of special, proprietary fibers. He claims that in
The problem is that just slowing down the setting time addition the fibers do not in any was impede detail but
doesn't produce the optimum life casting material. (See "How actually improve the consistency so that the alginate will
to Extend the Setting Time of Alginate" by yours truly in the better stay in place on the subject without running off. Let's
March, 2003 issue of Sculpture Journal.) Along with some see.
other features, the ideal life casting alginate also must be just
the right compromise between two of its opposing Devising a Testing Procedure
characteristics, strength (tear resistance) and durometer
(hardness/softness). Alginate can be manufactured to be very When Ed asked me to take a look at his pride and joy and
strong but it will also be very hard. Make it soft and it will give him my honest opinion, I had to devise a method to
also be fragile. If very soft, the alginate will easily tear, determine if his patent pending fibers really do increase the
particularly with thin structures. On the other hand, a very strength. I could have just poured out puddles of several
strong alginate can be so inflexible that it will tear rather than different alginates, let them set up, and pulled them apart to
pull free from tight places. One of the more common determine relative tear resistance. But that would have been
problems occurs when c
too subjective. I needed a way to actually measure the
strength.