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The trickiest and most interesting part of electroforming beads is the design
process. Because copper does not adhere to glass, the attachment must
necessarily be one of entrapment. The physical shape of the bead must prevent
the copper from falling away.
Conventional bicone or round bead shapes offer a number of design concepts for
entrapment. The most obvious is a cage structure. For a regular pattern, a
Sharpie can be used to mark crossing lines before using a fine brush to apply
the conductive paint. An organically-shaped cage works well as long as a
sufficient surface area is covered with metal -- long, narrow lines of metal can
be weak. Caging the bead with protrusions on the surface such as raised stringer
or dots may also hold the copper in place. A waist constriction is another
effective entrapment method, as in Kate Fowle's
electroformed beads that often
incorporate a structure that resembles two fused bead shapes. Openings in the
bead are one obvious way to prevent escape of the metal. Most of the designs
I've seen in the bead world follow either the cage or waist type attachment
methods, but possibilities for attaching electroforming are myriad if the bead
design is more unorthodox.
To prepare the bead for electroforming, first clean the bead to remove any oil
or dirt that may prevent the conductive paint from adhering. Etching the bead
can provide a bit more tooth to hold the paint. Remember that the finished
surface will never be smoother than the paint appears, and may roughen
substantially at any points of irregularity. If a smooth surface is desired,
then the paint must be free of brush lines. Multiple thin coats of paint may
provide a better surface than one thick coat. Try to avoid touching the
conductive paint as oil from fingers may inhibit copper growth. The paint needs
to be completely dry before immersing in the solution.
I'm most often asked "How do you get the controlled texture on your metal
coating?" The answer is that the metal coating will echo the surface I present
to the solution. For a smooth surface, take pains to apply the paint smoothly.
For a beaded edge to a line of metal, apply tiny beads as desired. All that
matters is that the surface is conductive. Anything that can survive coating
with paint and immersion in acid is usuable.
Janelle Zorko attaches real leaves
and flowers to her beads with fiber cord.
Ann Davis sculpts her designs from
jeweler's wax and then paints them.
Kate Fowle uses tiny glass marbles. The
drawback to any of these methods is the degree of delicate and time-consuming
work, but the results can be breathtaking.
The final consideration in preparing the bead for electroforming is the point
of electrical attachment. Many beads work well when suspended by a copper wire
running through the mandrel hole and turning up at the bottom, with the end of
the wire in contact with the dry conductive paint at some point. Actual
attachment with paint is not necessary, nor desirable, as then the wire would
become part of the bead. Since copper deposition is blocked at the contact
point, moving the wire several times during the process prevents formation of a
pit on the surface.
In the next discussion, I'll have photos of the components and assembly with a
full guide to putting the process in motion.
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