Are There Differences Between Lead Bearing and Lead Free Enamels?
by Bill Helwig, from Volume 10, Number 1, February, 1991
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Yes, both are vitreous enamels,
just as a Ford and a Dodge are both automobiles. Both are different types
of the same general thing. People who drive automobiles have a
preference, just as those who enamel also have a preference. The ability
to drive an automobile, like the ability to enamel, depends completely upon the
individual, providing everything else is in good working order. Unlike
enameling, driving requires a license. The license is a document that
indicated that basic skills for driving and knowledge of the rules of the road
have been met at a particular point in time. Any average person can learn
to drive, just as any one can learn to enamel. If it be a Ford or Dodge,
lead bearing or lead free enamel, the simple facts are that it doesn't matter
which are used. Both are just what they are, a car and an enamel.
Neither make a professional driver or enamelist. It is up to the
individual, through his or her skill and methods of operation that such a level
of status or state of satisfaction is acquired.
Somewhere amid illusion, delusion,
and fact everyone becomes predisposed. Attitude, accessibility, learning
and necessity are elements that influence and categorize actions into levels
that typify expression and display. There are obviously differences
between a Rolls Royce and a Hyundai. However, both are automobiles.
There is comfort or discomfort to both eye and body depending upon personal
preference, yet both can transport a person from one point to another
point. It is a matter of which is desired, which is survived, which
fulfills the requirements that are needed to be met. The question is not
about 'how' one arrived, but about that they arrived barring accident.
The enamel used is not the question. Did what was used meet the standards
necessary to have been used in the first place? Did the material allow
the user to travel from one point to another without accident? If an
accident did occur, was it the fault of the driver or the car; the enamelist or
the enamel? Which 'maker' is most culpable? Every maker is capable
of producing a product that is less than standard or that blurs
differentiation. Conclusions can not be jumped to nor assumed based on
outright prejudice. No two products ever produced are ever completely the
same, there may however be a vast amount of similarities that liken one to
another. The fact remains that there are more variables with the user
than the product used when it comes down to the ability to enamel.
The question about the differences
between lead bearing and lead free enamel is the same as the questions about
the difference between lead bearing and lead bearing, or between lead free and
lead free. There are more differences between enamelists than there are
between enamels when it comes to fiction versus fact. Assuming that both
of what is being compared are of equal quality, there can be only one source
for any major disparity aside from the initial manufacture of a specific
vitreous enamel batch, in which case the results would be generally the
same. The ability and knowledge of the person enameling becomes the
central issue and source for the differences aside from the technical/chemical
facts.
When a person only knows the tricks
of the trade without knowing the basic logic of the processes, that person is a
victim to every iota of difference regardless of any previous instance of
success.
Unfortunately, the majority of
those actually applying vitreous enamel to metal and firing such a piece only
know the 'step-by-step' for that process or those pieces. There are few,
if any, professional enamelists currently enameling in either art or industry
that do not rely on data that they individually have not experienced. All
mankind, must reference knowledge and experience of the previously pondered,
both from history and themselves. Procedural information does not always
transfer from one enamel to another, nor does it transfer from one process or
project to another. Most of what has been taught is procedural and in
accord only to the limitations of the teacher. Examples of this abound
and are even written into books where the printed word is read as if it were
truth. Very little of what is being currently written and published for
or taught to the artist and or leisure hobbyist is indicative of anything other
than 'a personal approach'; without supporting logic or documentation that
relates to either the history of or the technology within the context of that
which has been, is, or can be.
Not a day goes by where one does
not learn, have reinforced, or discover additional facts and relationships
about the whole process of enameling. Continual enlightenment pushes
further and further until all is a boundless territory of choice. One
should reel under all of the potentials and possibilities from which to
choose. If for some reason one becomes locked into a death like grip of
being helplessly bound to only one choice and the repetitive procedures neither
add or improve either the quality or efficiency of their work, then it is time
to question whether a trap has been fallen into or not. If the same
routine with the same results for the same reason does not bring joy, to the
intensive endeavor of enameling, then the inhibiting factors must be removed.
It does not matter which vitreous
enamel a person uses. It matters not whether it is opaque or black or
transparent or green or red or ruby or lead bearing or for glass or lead free
or for aluminum or in liquid form, it all makes no difference providing that
the whole of that which is produced is aesthetic for the purpose it was
created.
Over the past twenty five or so
years I have used for personal work and taught with both lead bearing and lead
free vitreous enamel. Today I still use both, however the majority of my
current work is with that of the lead free material. I advise and consult
individuals and companies about vitreous enamel; problems and procedures, lead
bearing and lead free, it matters not as long as quality control is
gained. By choice I currently teach with lead free material because of
the advantages I feel it has to offer and to be current or abreast with
technological advancements. I make no claims about being more correct,
any person working with enamel on a constant basis improves with insight
providing they are not hampered by preconceived authority. Again by
choice I use that enamel which will serve my purpose for the best results with
the limits of my knowledge and abilities.
Yes, I remember the good old days
when 108 transparent Forsythia yellow could solve all of my problems and I
still have some of that lead bearing uranium colored enamel tucked away.
But times have changed and I have changed and that bag of enamel does not
dictate to me what I can do, even though I've more than enough to create many
pieces.
The consternation is not about lead
versus non lead enamel, it is about change and the ability to change for those
who have been working with and dependent upon lead bearing enamels for a number
of years. To that problem it can only be said that constructive criticism
is far more positive than egocentric cries of foul play.
When it comes to art does it matter
if it is lead bearing or lead free? Simply put, the answer is no.
The responsibility for art belongs first and foremost to the artist, the
creative person who contributes through forms of expression that which can not
be denied worth. Like it or not, there are very few who are that select,
most of us struggle to rise above the average within any given field. The
question has merit only in theory. Worth does not depend upon any one
material, rather it depends wholly upon the individual at any given point in
time.
When it comes to safety does it
matter if it is lead bearing or lead free? Again simply put, the answer
is no. When it comes to personal, private, or public safety, everything
must be considered toxic. Everything harbors potential danger. If
not in itself, then in its confrontation with man. Danger can
not be removed if one anticipates living on this earth. Laws were created
to protect man against himself. Laws were also created to socialize
groups of people into organized cultures of hierarchy. We now have laws
that reduce our exposure to lead, but that does not mean that we live in a
safer world when one considers the more rampant killers.
When Thompson Enamel stopped
producing lead bearing vitreous enamel for the artist in 1990, it was the last
and only company in the United States doing so. Laws had made it unprofitable
in terms of business and it is important not to forget that Thompson Enamel is
a business first. They sell a product for profit, that is their business.
The absence of a US manufacturer
will not detour the enamelist, nor will the use of lead free vitreous enamel
decrease the quality level of items produced. The replacement of lead
bearing with lead free vitreous enamel will reduce the problem of exposure to
lead due to sloppy hygiene and careless work procedures for those using lead
free material, but if hygiene and work procedures are not also improved, some
other toxic material will probably take its place. Only the individual
can improve his or her work habits and so to speak, clean up their act.
As to the specific differences
between lead bearing and lead free, their advantages will be listed
first. This listing will compare those lead bearing enamels that were
produced by Thompson Enamel with the lead free enamel produced by the same
company. This comparison does not include or preclude similarities for
lead bearing materials produced by foreign manufacture. Such a comparison
would probably have an equal number of similar facts among the more common
types and colors of vitreous enamel. These differences must be stated in
generalizations because no two enamels are alike, unless they are from the same
batch. Also, for example, a transparent red made from gold and a
transparent red made from cadmium selenium, while both transparent and red and
vitreous will always be considerably different under all conditions whether
they contain lead or not.
LEAD FREE VITREOUS ENAMEL ADVANTAGES
Lead free will by volume weigh less
Lead free will be more acid resistant.
Lead free may be ever so slightly harder (scratch
ability).
Lead free may absorb more copper oxide from the metal
surface.
Lead free may have a larger coefficient of thermal
expansion.
Lead free will have less water solubility.
Lead free will have a slightly higher softening
temperature.
Lead free opaques will have less color variation due
to different firing time/temperature relationship.
LEAD FREE AND LEAD BEARING EQUALITIES
Index of refraction.
Workability.
LEAD BEARING ADVANTAGES
Lead bearing has a slightly decreased skin texture.
Lead bearing currently has a greater color selection.
Lead bearing has lead arsenate opal colors.
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