Sunday, September 7, 2008

Precious Metal Clay Beads

Nope. This is not a picture of some alien form of plant life, or a scientific model of a Universe of oddly shaped planets. It's one of the things I have been working on lately... fine silver precious metal clay over porcelain beads.

There are 3 kinds of beads that I make using the fine silver of Art Clay Silver or PMC ~

*Hollow Silver Beads
*Solid Silver Beads
*Silver Overlay Beads

Hollow Fine Silver Beads
Hollow beads are made by putting silver over a core material that will burn out during firing in the kiln. (You should not try this with a torch.). There are many possible materials you can use. The most common are paper clay, cork clay, cereal. Yep, that's right.... breakfast cereal like Cheerios & Kix make great cores for beads, though it is pretty fragile to work with. Paper clay is a bit of a pain in my opinion because it does not completely burn away. You must chip it out of the center of the bead after firing. For me, cork clay is the perfect core medium. It is easy to form and it completely turns to fine ash when fired. This is how I do it...

Form the desired shape in the cork clay and let it dry for at least a day. Insert a wood toothpick into the cork where one of the bead holes will be. Don't put it all the way through, just insert deep enough to secure it in the cork. Break another toothpick in 1/2 and coat it with a non stick medium like "Slik". Stick this on the other side where the hole will be. This one will be removed before the bead is fired to allow a place for the ash to fall out of. Prepare a 'mandrel stand' by sticking a chunk of polymer clay to a plastic lid. Use the long toothpick as a mandrel to hold the bead while you work on it. Coat the cork in melted wax or a thick layer of water soluble glue, stick the toothpick end into the polymer mandrel stand and let the coating dry completely. The wax or glue will burn out faster than the cork, allowing a little wiggle room to accommodate the shrinkage of the silver clay & it keeps silver from flowing into the porus core surface. After the coating is dry, cover the bead in a thin rolled sheet of silver clay, syringe clay or use a paintbrush to paint the bead with silver clay paste. If using the paste method, you must use at least 5 layers of paste, letting each layer dry before adding the next. Once you have your silver base, decorate using syringe clay, paper clay, etc. Let it dry. Remove the short toothpick. Place the bead open hole side down, on a bed of fire blanket or vermiculite. Fire per manufacturers instructions. I fire my low fire ACS at 1270 for 30 minutes. The cork burns out around 700'. Until that point, you must leave the top vent of the kiln open. You will smell the cork burning and see a puff of smoke. (Be sure not to breath it. Work with plenty of ventilation.) Plug the vent hole after this occurs. After the beads are cooled, finish as you would any metal clay pieces.... burnish, tumble, antique, polish, etc.

Solid Silver Beads
This type of bead is pretty self-explanatory. Form metal clay into the desired shape, put a hole in it, fire and voila! You have a solid silver bead! Some ideas... After forming the desired shape, stick a wood toothpick all the way through to form the holes & keep them open during firing. In the kiln, they will simply burn away. Or you can use professional bead mandrels made especially for this purpose. You can form large hole beads or tube beads by wrapping a sheet of clay around a drinking straw. Remove the straw from the dried clay before firing.

Silver Overlay Beads
This type of bead involved putting a layer of silver over a core that does NOT burn out during firing. The core remains he center support for the outer silver surface. I have heard that brass and steel can be used for a core, but I have no personal experience with that. My favorite core material to overlay is porcelain. I prefer this method to the two bead styles mentioned above because the overlay beads use less silver, weigh less than solid beads and cannot be crushed like hollow beads. How I do it...

Form a mandrel from a drinking straw by cutting a slit about 3/4" long on one end of the straw, then cut a small slit perpendicular to that at the end of the first slit.
Roll the cut end of the straw into a tighter tube and insert into the bead. The tension from the straw should be strong enough to hold the bead on it securely so that you can work on the bead while holding on to the straw. Coat the bead in at least 5 layers of paste clay, letting each layer dry thoroughly. Decorate with syringe clay, sheet clay or stamped clay, etc... When it is dry, fire per manufacturers instructions. Burnish, tumble, antique, etc...

Visit my shop . Many new beads & fine silver findings to be added to the store soon!

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