BRONZclay Tools and Supplies for Making Bronze Jewelry
Tools and Supplies for Working With BRONZclay Bronze Metal Clay
Bronze metal clay is a malleable, clay-like material that can be rolled, cut, shaped, molded, textured, sculpted or carved, and then fired at high temperatures to create pure bronze metal objects, such as jewelry, hair ornaments, small sculptures, decorative utensils, etc.
It's more affordable than silver metal clay and can take a chemical patina or a colorful heat patina if desired. Original BRONZclay has a high percentage of binder that makes it easy to carve and produces a higher shrinkage rate that brings out detailed textures beautifully.
The metal clay community started with just two brands of bronze clay, BRONZclay (invented by Bill Struve, PhD. of Metal Adventures) and Hadar's Clay (invented by Hadar Jacobson of Textures Studio.) I have written an in-depth article about working with original BRONZclay that contains detailed tips and techniques for working with this versatile bronze jewelry making and sculpture material. The current article is a companion to that one and focuses on the tools and supplies you will need for working with this metal clay formula. You can learn more about Hadar's Clay brand bronze clay formulas on Hadar Jacobson's blog and about the other bronze clay brands and formulas in my bronze clay article and on the manufacturers' respective websites.
Do You Use More Than One Type of Metal Clay?
Which types of metal clay do you work with?
Basic Metal Clay Tools and Supplies
You'll need brushes, pin tools, playing cards or spacers, non-stick sheet, textures, and other basic metal clay tools and supplies. See my Metal Clay Materials, Tools Supplies and Equipment article for a detailed list of must-have and nice-to-have items.
Activated Carbon (Firing Media)
BRONZclay is buried in layers of activated carbon during all or most of the firing schedule to allow the clay to sinter without the inhibiting presence of oxygen (O2). During firing, the activated carbon releases carbon dioxide (CO2). Since CO2 is heavier than O2, it settles at the bottom of the firing container and gradually displaces the O2, which is pushed out the top of the container.
Two types of activated carbon media can be used for firing BRONZclay:
- Coal activated carbon sometimes can produce colorful iridescent or "rainbow" patinas during a limited number of firing cycles. The colors can be spectacular, but the results are unreliable. Acid washed coal carbon comes from many sources; if you get a bad batch, your pieces may develop a thick, tough black coating during firing that must be removed with a hydrogen peroxide pickle, so make sure to purchase it from a reliable metal clay supplier.
- Coconut shell activated carbon produces natural, satiny gold-brown patinas that sometimes include lovely, subtle colors. It is made from a renewable resource, so it is a more environmentally sustainable choice than coal-derived carbon. It also is more consistent and reliable from batch to batch, and is the preferred type of carbon for firing COPPRclay, Metal Adventures' brand of copper metal clay.
Activated carbon sold for use with aquariums can have undesirable additives. It is safest to buy activated carbon firing media only from a BRONZclay dealer.
Mardel Rein of Cool Tools worked with a manufacturer to develop her own brand called Magic Carbon that is produced to her proprietary specifications to allow any brand or formula of clay - including PMC Sterling and PMC Pro carbon-fired silver clay - to sinter faster and at a slightly lower temperature than most other activated carbon firing media. Although she has not divulged much about the characteristics of Magic Carbon other than the advantages it offers in the sintering of metal clay, it seems likely that either coal or, more likely, coconut carbon that has been treated to give it the desired characteristics. Magic Carbon produces what Mardel calls an "antique patina." Depending on the desired look, that dark brown patina can be left on the metal, eliminating the need for a separate patina treatment using heat or chemicals,
Another consideration when choosing between coal-derived and coconut shell-derived activated carbon is that fired BRONZclay (i.e., bronze metal) can be colored vibrantly with more controlled heat or chemical patinas. For more information on adding controlled heat and chemical patinas to your bronze pieces, see the "Finishing BRONZclay" information in my companion article on working with BRONZclay.
Stainless Steel Firing Containers / Firing Pans
Any covered stainless steel container can be used to hold the activated carbon granules and BRONZclay greenware. Most artists use square 22 ga stainless steel covered steam table pans 2.5", 2.75" or 4" tall/deep (used by restaurants and caterers). You can purchase firing pans from most suppliers that carry BRONZclay or from a restaurant supply house. Mardel Rein of Cool Tools warns against buying stainless steel pans that have been plated to make them shiny; the plating will pop off inside your kiln as the pan heats and cools. Bill Struve has found that pans from China are more likely to flake off in this manner. Don't worry if your pans darken in the kiln; it's perfectly normal.
One of the firing pans I use for firing base metal clay pieces is a 22-gauge, 18/8 stainless steel, (6-7/8" long by 6-3/8" wide) that's 4" deep. It's a great size for firing large or tall pieces or multiple pieces of bronze clay (or any other carbon-fired metal clay). It also comes in shallower and deeper versions. sixth-size steam table pan
Tip: Before buying any metal clay firing container, make sure to measure the interior dimensions of your kiln's firing chamber. There should be enough space around all six sides of the container (including the top and bottom) for the hot air to circulate freely.
Firing Container Lids
Even though base metal clays fired in activated carbon are sintered in a reduction environment with very little air, a small amount of air needs to be able to enter the firing container in order to support combustion of the binder during the burn-off phase of firing (unless you do a separate binder burn-off firing phase, which uses up a lot of activated carbon).
The easiest approach to venting the pan is to get a stainless steel steam table pan cover that fits your firing pan and has a small opening designed to accommodate the handle of a serving implement (or drain foods in liquid). These are called slotted, perforated or notched steam pan covers, depending on the manufacturer.
Other options include cutting a long, narrow rectangular slit in a solid steam table pan cover, or propping up one corner of the lid with a small scrap of Solderite board or kiln shelf.
Activated Carbon Storage Container
You'll need an airtight container for storing your activated carbon between uses. Gail Lannum recommends storing carbon granules in a cereal storage container designed for pouring, such as those by Snapware Snap 'n Lock, KLIP IT or Lock & Lock brands. Make sure to choose a storage container that is large enough to store a couple of pounds of activated carbon and that has a built-in area for your hands to comfortably grip and pour the carbon into your firing pan.
This Snapware Cereal Keeper holds slightly less than 23 cups, so it's great for storing activated carbon. It's airtight to keep the carbon fresh and effective, has an easy-to-open flip top lid for pouring activated carbon into your firing containers, and has an ergonomic design that makes it easy to grip securely, which is especially important when you're hefting a large container of activated carbon.
Use distilled water only (not tap water or spring water) when working with BRONZclay (making paste/slip, rehydrating the clay, moistening areas to be attached, etc.). Distilled water is available at drugstores and some grocery stores.
Tip: Distilled water usually is sold in the same plastic gallon jugs as spring water. Often both kinds of water look nearly identical and it's easy for them to end up on the wrong shelf. So learn from my mistakes and check each bottle's label to make sure you're getting distilled water.
Olive Oil and Other Clay Release Agents
Olive oil is used to condition BRONZclay. It also is the recommended release agent for your hands, tools, textures and work surfaces, although some artists also use other release agents such as Cool Tools' Slik balm or ClayMate hand conditioner on their hands and Badger balm, Burt's Bees balm, Cool Slip or HattieS No Stick spray on their tools and textures.
If the skin on your hands is extremely dry, as mine are, it will suck up moisture from any metal clay, whether base metal or precious metal. Either apply extra olive oil to your hands or, if you prefer, apply a thin layer of skin shielding lotion or protective balm, such as Gloves in a Bottle or Slik, to your hands and nails before coating them with olive oil. Gloves in a Bottle is available from some metal clay suppliers and also some drug stores.
Tip: Lora Hart recommends keeping separate containers of non-spray releases (olive oil, Badger Balm, Slik, etc.) for bronze/copper clay and silver clay to avoid cross-contamination.
Search and Retrieval Aids
Sifting Spoons, Tongs and Uncoated Wire "Finding Wires"
Long-handled slotted spoons or tongs can help you locate and retrieve your fired pieces amid the carbon granules. You may be able to find an old, long-handled slotted cooking spoon or pair of tongs at a yard sale, or you can buy a sifting spoon, sifting scoop or wire skimmer from Metal Clay Supply, PMC Connection and other metal clay suppliers or kitchenware stores.
You can string small charms, dangles, beads or other components onto pieces of uncoated brass or stainless steel wire and twist the ends to make the pieces easier to find and retrieve after firing. I've nicknamed these twisted wire loops "finding wires", since their purpose is to help you find small components and beads buried in activated carbon.
Stainless Steel Wire Brush(es)
Because bronze metal is so hard, burnishing it with a brass brush (like the ones used on fired silver clay) would take hours. To achieve a wire-brushed satin finish on fired BRONZclay, use a stainless steel wire brush with soft/crimped bristles.
A steel-bristled hand brush works fine. However, if you often polish several pieces at a time or polish multiple times a day, motorized brushing will be faster and more efficient. You can buy stainless steel wire brush burs in several shapes and sizes that can be mounted on a rotary tool, flexible shaft tool or polishing lathe. As always, remember to wear proper protective gear when working with power tools.
Unless you are committed never to remove your firing pan from the kiln before it has cooled to room temperature, you'll need a pair of heat-resistant gloves to protect your hands. Zetex Plus gloves provide excellent heat protection (up to 1500F to 2000F direct heat), but they're large, stiff and can be clumsy to work with. Kevlar gloves are more comfortable than Zetex Plus gloves and are fine for this purpose as long as you don't use them inside a still-hot kiln.
is the most comfortable option. They provide excellent heat protection and can be more economical. They also usually fit women's hands better, so if you're a woman, that's another advantage. A good-fitting pair of leather welding gloves
When working with BRONZclay, you should follow standard safety practices, such as working in a well-ventilated area, tying back long hair before opening a kiln, working near an open flame, or being near power tools. One of these is to wear appropriate protective eyewear.
Simple safety glasses/shop goggles can provide impact protection against flying metal and other objects, especially when you are using power tools. If you are opening a hot kiln (tsk, tsk!), soldering, or flame-coloring bronze metal, you will need additional protection against ultraviolet and infrared rays. Consult with your eye care professional before shopping for protective eyewear, and buy from a knowledgeable supplier, such as Rio Grande or Aura Lens.
Particulate Respirator(s) (Optional)
Particulate respirators can help protect you against breathing in dust, metal or metal clay particles (from sanding, grinding, filing, sweeping). Respirators are rated by National Institute for Occupational Safety and Health (NIOSH) according to the types of substances they filter. A simple, lightweight, disposable dust respirator (such as 3M model 8210 or 8212) can be a good choice for routine wear and is suitable for sanding, grinding, sweeping, bagging or working under dusty conditions.
Soldering and application of chemicals such as patinas always should be performed in a well ventilated area, preferably one with a fan positioned to draw away the fumes and a hood vent to remove them. Some respirator models (such as the 3M 8212 and 8515) can provide an additional layer of protection against inhaling solder/welding fumes, if you wish. Chemicals patinas produce different types of vapors. Consult with a knowledgeable expert and read the labels carefully if you are looking for a respirator to protect you when you are working with these chemicals.
In addition to disposable models, particulate respirators are available in non-disposable styles used with disposable filters. Filter cartridges need to be replaced frequently. Check the label to see how many hours of protection yours provide.
In order to provide their intended protection, respirators need to fit snugly against the face with no gaps in the seal. There are some models designed specifically to fit people with smaller facial features.
There are many different makes and models of respirators. Choosing the best model for your individual needs can be confusing. In addition to reading labels carefully, it's a good idea to ask a trusted supplier for guidance. Particulate respirators are sold by hardware stores, medical supply stores and some jewelry suppliers, including Rio Grande, and Otto Frei.
Firing Fork (Optional)
If you have a front-loading kiln, you may want to try using a two-tined firing fork to remove your firing pans from the kiln, depending on the type and width of your pan(s). Firing forks are available from Rio Grande and Cool Tools, among other suppliers.
Note: Do not confuse firing forks with kiln forks, which are used in enameling.
Pure Essential Lavender Oil or PasteMaker Metal Clay Paste Additive (Optional)
If you want to make BRONZclay oil paste, you will need pure essential lavender oil or Sherri Haab's PasteMaker paste additive. PasteMaker is available only from Metal Clay Supply.
Pure essential lavender oil is available from some metal clay suppliers, including Cool Tools, PMC Connection and Metal Clay Supply, in some health food stores, and from lavender farms such as Purple Haze Lavender Farm.
Creative Paperclay and/or Ceramic Fiber Kiln Shelf Paper (Optional)
For some projects involving both BRONZclay and pre-fired silver clay, you may need to cover the silver with Creative Paperclay (made of volcanic ash) and/or ceramic fiber paper. Creative Paperclay is available from Cool Tools, New Mexico Clay, and from craft supply stores. Ceramic fiber paper can be purchased from Cool Tools, New Mexico Clay, Art Clay World USA, Metal Clay Alchemist, and wherever glass fusing supplies are sold.
Bronze, Brass and/or Copper Wire (Optional)
Many artists have embedded and fired copper, brass and bronze wires in BRONZclay successfully. Genuine bronze wire can be embedded with fairly reliable results. But not all copper, brass or so-called "bronze" wires are stable after being kiln-fired in carbon.
Many companies sell bronze-colored heat-treated or coated brass or copper wire, which often is referred to as "commercial bronze," "jeweler's bronze," or some other variation. These wires may be fine for findings or cold connections. However, unlike genuine untreated bronze wire, their appearance and/or performance are likely to be adversely affected if they are embedded in BRONZclay and carbon-fired in the kiln.
Genuine bronze wire is made of copper and tin, usually in a ratio of 90–92% copper and 8–10% tin. Kevin Whitmore of Rio Grande recommends asking suppliers whether their "bronze" wire contains any zinc. If so, it made of brass and not true bronze. Cool Tools, Rio Grande, and Metal Clay Supply all carry true bronze wire.
Before you buy an entire spool of brass, copper or bronze wire to embed in BRONZclay, ask for a sample and run it through a full BRONZclay firing cycle with your next kiln load. After the wire has cooled completely, check to see whether the color has changed. Look for surface chips or peels (indicating that the wire was coated). Bend it with pliers to see whether the wire cracks or breaks because the prolonged high heat made it brittle.
Embeddables Bronze Metal Findings
Eyelets, Bails, and Gem Settings Designed Specifically for Embedding Into BRONZclay
Embeddables are findings designed to be embedded into metal clay and fired in place. There are Embeddables for BRONZclay (and also for silver clay and COPPRclay), including eyelets, bails, and gemstone settings for faceted round stones, AKA chatons.
Embeddables are available from Rio Grande, Cool Tools, and Metal Clay Supply, among other metal clay suppliers.
Fine Silver Bezel Cups (Optional)
Fine silver bezel cups can be embedded in BRONZclay and used to set both stones that can be fired in place and those that must be set post-firing. You can find good selections at Rio Grande, Cool Tools, and other jewelry and metal clay suppliers.
Accent Silver (Optional)
You can add silver accents to your fired BRONZclay pieces with Accent Silver, a powder made from a silver alloy that is rehydrated to a slip consistency as needed. Two coats are applied to clean metal and allowed to dry before kiln firing in coconut shell-derived carbon and burnishing with a steel-bristled wire brush. The silver bonds permanently to surface of the base metal.
Accent Silver can be applied to any clean, untreated and uncoated copper-bearing base metal (bronze, brass or copper), on any piece that will fit in the supplied firing container, including sheet, wire or castings.
You can buy Accent Silver separately, or get the well-equipped starter kit that includes everything you need except distilled water and a kiln (an UltraLite with the Flat Cover may be used):
- 5 gram jar of Accent Silver powder
- Stainless steel bristle wire hand brush
- Stainless steel bristle wire scratch brush
- Two small acrylic mixing discs
- Mini palette knife
- Natural bristle application brush
- Stainless steel covered firing container filled with coconut carbon
- Firing tongs
- Fine Scotch-Brite pad
- Natural beeswax pearls (to hold your piece steady as you apply the silver slip)
- Brass medallion stamping (to practice on)
Accent Silver is available from some metal clay suppliers
Clay Humidifier and/or Flexible Pouch (Optional)
Your working clay should be kept in a humid environment during your work session to prevent it from drying out or cracking. If you store your BRONZclay in a humidifying environment inside a plastic food storage container (see the "Storing BRONZclay" section of my article on BRONZclay), you can tuck your working clay back into the container during your session, if you wish. Following are two good alternative approaches to keeping clay moist during a work session.
A clay humidifier is a very convenient way to keep your working clay moist. You can purchase one of Donna Lewis's LiL BeLLA humidifiers (see my review on my Metal Clay Product Reviews page), or you can create a makeshift clay humidifier by gluing the "hook" side of a short strip piece of Velcro to the inside of an inexpensive drinking glass ("old fashioned" size) and gluing the "loop" side of the Velcro to a small piece of kitchen sponge with Amazing GOOP or another flexible waterproof glue. When you are ready to open your clay, wet the sponge, squeeze out the excess water so it doesn't drip, and attach it to the inside of the glass with the Velcro strip. Invert the glass onto a small, flat plate or on a piece of plastic wrap on a convenient corner of your worktable. Lift the edge of the inverted glass, slip your conditioned working clay onto the plate or plastic wrap, and replace the glass to keep the clay moist. As you work, just lift the edge of the glass, pinch off and remove another piece of clay, and replace the glass. Tip: Wet the rim of the glass with water to help create a seal.
Another option is to tuck the unused portion of your working clay into a small flexible storage pouch, such as the ClaySafe or ClayVault from Metal Clay Supply during your work session. Metal Clay Supply recommends wrapping BRONZclay in plastic before placing it into one of these flexible pouches. To keep the storage environment moist, the ClayVault comes with an absorbent crystal that is soaked in water and placed inside the pouch along with the loosely wrapped clay (the plastic wrap keeps it from touching the moisture crystal directly). If you're using the ClaySafe, dampen a small scrap of sponge and tuck it into the pouch along with the loosely wrapped clay. Important: Label the pouch "BRONZclay" and use it only for that formula.
Shared vs. Dedicated Bronze Clay Tools and Supplies
Other than the items mentioned above, for the most part bronze clay is formed, textured, pre-finished and finished using the same tools and supplies as those used with precious metal clay (PMC or Art Clay, silver or gold). However, it is important never to contaminate your precious metal clay with base metal clays, such as bronze or copper clay, and vice versa.
Clean brushes and non-porous items like metal, hard plastic tools, non-stick sheets and texture mats/sheets thoroughly before switching from precious metal clay to base metal clay or vice versa. If you prefer, you can purchase a duplicate set of tools and use them exclusively with base metal clays. You can wipe playing cards clean with a damp paper towel or wet wipe, if you wish, or keep a separate set of cards for bronze and copper clay.
Keep a separate set of supplies that cannot be cleaned thoroughly, including sandpaper, sanding pads, salon boards, etc., dedicated to base metal clay exclusively. Metal files can be difficult to clean well and should not be washed. You can either brass brush your files thoroughly (you may wish to use a file card first to dislodge the accumulated metal clay filings), or buy a separate set of files to use on base metal clay.
Celie Fago doesn't keep separate tear-away textures for bronze clay. Since a thin layer of olive oil should be applied to metal clay before using it with a paper-backed polymer clay tear-away texture, the clay should not stick to the tear-away sheet. Be sure to inspect your tear-away textures before using them with more than one type of metal clay (bronze, copper, silver, etc.) to make sure there is no residue that could contaminate another type.
Questions & Answers
© 2009 Margaret Schindel