Impress your clay and your friends with UV-etched solar-plate molds. all levels reference. by Maggie Bergman. Kissed. Sun. by the FCT-CRON0216_ART25

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1 Impress your clay and your friends with UV-etched solar-plate molds all levels reference by Maggie Bergman FCT-CRON0216_ART25 Kissed by the Sun

2 olar plates, or photo-polymer plates as they are also known, are light-sensitive printing plates used by professional printers. The plates are available from most graphics companies and photography shops, and they come in different thicknesses with either a steel or plastic backing. A solar plate can be etched by covering it with a transparency printed with black artwork, then exposing the plate to UV light. The emulsion (the gelatinous, light-sensitive surface of the plate) hardens where it is not protected by black lines. The plate is then washed, and the soft emulsion that was protected under the black lines washes away, leaving the hardened emulsion raised in relief a perfect mold for shaping clay. Once you become familiar with this process, you ll be able to create a solar-plate mold in just five minutes. Read on to enhance your knowledge of these fascinating plates, and then try a pendant project using your custom-designed solar-plate mold. artwork options 46 There are only two artwork requirements for making solar plates: The artwork must be solid black and white. Other colors (including grayscale tones) cannot be used, as they do not block out the UV light completely. The final artwork must be on a transparency. There are a few ways to transfer artwork to a transparency: Photocopy black-and-white artwork (hand-drawn or purchased) onto a transparency. Scan artwork into a computer, then print it onto a transparency using a laser or inkjet printer. (Transparencies available for inkjet printers are more facetjewelry.com a b expensive than the ones suitable for laser printers.) If you d like, you can invert the black-and-white areas of your artwork using a computer graphics program, such as Adobe Photoshop, then print it onto a transparency. (If you don t have access to office equipment or software, visit a photocopy center where professionals will do the job for you. They can photocopy, scan, print onto transparencies, shrink and enlarge images, etc.) Draw directly on the transparency using an overhead transparency pen, making sure it produces dense, black lines. One exception to using a transparency: Place materials, such as paper cutouts, lace, leaves, or machine and clock parts, directly on the solar plate. Cover them with glass, place the plate in the exposure frame, clamp everything together, and then apply UV light. In the original artwork and its inverted image [a], the black areas were planned to be recessed on the solar plates after exposure [b]. Part 1: Working with solar plates Planning a solar plate from artwork All black areas of your artwork will become recessed in your solar-plate mold after exposure. If you then press clay into the mold, the recessed areas will become raised on your clay piece. Consider this carefully before choosing your artwork. See Artwork Options, left, for some guidelines. Whatever artwork you choose, be sure the design lines have a minimum width of 2 points (0.7mm). Fine lines have a tendency to disappear during the washing of the solar plate. Cautious usage Prior to exposure, solar plates can be handled safely in any non-uv light normal fluorescent lighting is fine. Keep the plates away from sunlight or any artificial UV-light source until you are ready to expose them. Even when leaving your bench briefly, turn the plates face down or cover them unprotected emulsion will harden quickly, rendering the plate useless. Determining exposure time Follow the steps below to run a test exposure to determine the length of time to expose your solar plate to your UV-light source. Make a transparency. Transfer black-andwhite artwork to a transparency. See Artwork Options, left Kalmbach Publishing Co. This material may not be reproduced in any form without permission from the publisher.

3 Process photos by Maggie Bergman. 1 2 [1 2] Position the transparency. Cut a strip of solar plate [1] 3 8 in. (9.5mm) larger on all sides than the artwork on your transparency. See Sturdy Steel vs. Flexible Plastic, below right. Remove the cover film from the plate, and discard it [2]. Position the transparency on the plate with the printed side touching the plate. Place the plate in the center of an exposure frame (see Make Your Own Exposure Frame, page 49. [3] Conduct the test exposure. Visually divide your artwork into seven equal sections. Place a strip of thick cardboard on top of the glass, covering the transparency design for its entire length except the first section. Set your timer for 30 seconds, apply your UV-light source, and expose the first section. See Ways to Catch UV Rays, page 48, for UV-light-source options. After the first 30 seconds, switch off the light, reset the timer for 30 seconds, move the cardboard to reveal another section, and expose the test plate again. Repeat these 30-second intervals until all seven sections have been exposed. The last exposure will have received only 30 seconds of UV light; the previous exposure, 1 minute; the one before that, minutes; and so on. sturdy 3 steel vs. flexible plastic Solar plates come with either a steel or plastic backing. The steel-backed plates are stronger and need to be cut to size with either metal shears or a drawknife. Plastic-backed plates are flexible and can be cut with heavy-duty scissors. Buy steel-backed plates 0.9mm thick or greater. (The one used to make the featured pendant, is 1.52mm thick.) Buy plastic-backed plates 0.8mm thick or greater. 47

4 ways to catch UV rays Sunlight. Exposure times will vary. Expose a test plate on the same day and close to the time you d like to expose your final solar plate to determine the best length of exposure time. UV exposure box [a]. Construct this box easily with UV black-light tubes. Place the tubes as close together as possible to keep the spread of light even and to avoid hot spots. Leave about 4 in. (10.2cm) between the solar plate and the tubes during exposure. Exposure time should be short (about minutes). Black-light tubes have limited service lives. They can still be used after their service lives expire, though exposure times will increase. a Halogen desk lamp (50 watt) [b]. This light works very well, but more slowly than a UV exposure box an advantage in fine-tuning exposure times. Keep the solar plate 2 3 in. (51 76mm) away from this light during exposure. This wattage is good for small, jewelry-sized plates up to 4 x 4 in. (10.2 x 10.2cm). Exposure time is typically 5 10 minutes. (For conducting test exposures [step 3] with a halogen lamp, use 1-minute, rather than 30-second, intervals.) b Professional exposure units. Professional printing companies use these units. If you have access to one, run a test exposure to determine the best length of exposure time. materials Metal clay: 16g Metal clay paper Metal clay paste or white wood glue Enamel powders: transparent, #80, suitable for use on silver tools & supplies Overhead transparency, printed with black-and-white artwork 2 solar plates (photo-polymer plates): plastic- or steel-backed, 4 x 4 in. (10.2 x 10.2cm) Heavy-duty scissors; or metal shears or drawknife Exposure frame: Thin wooden board, craft wood, or masonite (about 2 in. [51mm] larger than artwork); bubble wrap or thin foam; tape; solar plate (prepared with transparency); glass ( 5 64 in. [2mm] thick, same dimensions as board); 4 large bulldog clips Cardboard, 2 x 6 in. (51 x 152mm) Timer, displaying seconds and minutes UV-light source Shallow tray Natural-bristle brush, soft (bootpolishing brush) Natural sponge (optional) Electric fan heater or hair dryer Sturdy, flexible work surface Olive oil Natural hand balm Playing cards Acrylic roller Paintbrush Craft knife Hotplate (optional) Sandpaper: 400, 800, 1200 grit Needle files Moist towelettes Thin straw or skewer Kiln setup: kiln, kiln shelf, steel trivet with steel trees, barbecue slide or enameling fork, kiln mitt Dust mask Small watercolor palette or small plastic cups Pipette or dropper Distilled water (optional) Synthetic watercolor brushes for enameling, nr 000 and nr 1 Finishing items: stainless steel brush, tumbler with steel shot and burnishing compound, alundum stone (optional), diamond files: coarse, medium, and superfine grades (optional), silverpolishing cloth, burnishing tool or flex shaft with rotary polisher (optional), fiberglass brush

5 make your own exposure frame Tape bubble wrap or foam, smooth side up, to a thin wooden board to cushion and even out the pressure on the glass. Lay your solar plate (with transparency in place) on top of the bubble wrap. Place a piece of glass over the top, and clamp the glass and wooden board together with bulldog clips. A small photo frame is a perfect supplier of the wooden board, or similar material, and glass you ll need. Wash out the design. Wash the plate in a shallow tray of 95 F (35 C) water for about minutes, gently scrubbing in a circular motion with a natural-bristle brush to remove the gelatinous emulsion from the corners and small lines. This water temperature and length of time prevent the emulsion from lifting away from the backing completely. Underexposed or overexposed sections on your test plate will not wash out very well or may not wash out at all. If none of the design washes out, the image is completely overexposed (hardened) try another test plate with shorter time increments. See A Customized Washout, above right, for information on controlling the depth of your design lines. a customized washout For deep design lines that wash away through to the backing, use a natural-bristle brush to gently scrub until you can feel that the hard backing material is no longer slippery (emulsion left on the backing will feel slippery). For shallow design lines, gently rub the plate with a natural sponge, checking your design often for the desired depth. Dry the plate. Absorb excess water from the plate with a natural sponge or lint-free paper towel. Dry the plate for about 10 minutes in front of a fan heater set to medium. Place the plate on its edge about 12 in. (30.5cm) from the heater. Or, use a hair dryer, being careful not to overheat the plate. The surface is fully dry when it is no longer sticky. Make conclusions. Determine which exposure section has the sharpest lines and the desired depth. Note the length of time that section was exposed to your UVlight source and the test plate s distance from the light. Record these numbers. A finished solar plate yields very defined design lines that flawlessly transfer to metal clay. 49

6 intermediate metal clay enamel 1 2 Use UV rays to quickly turn a solar plate into a custom-designed mold for use in this enameled metal clay pendant. Part 2: Butterfly-wing enameled pendant Champlevé enameling a process in which recesses are traditionally made in metal and then filled with enamel demands sharp, clean lines. Metal clay is often used to emulate traditional champlevé, but by its very nature, metal clay is more suited to soft, organic shapes than sharp lines. Solar plates make it easy to produce a mold with crisp design lines at home, from your own drawings or chosen artwork, and without the need for expensive equipment or dangerous chemicals. Conduct a test exposure. See Determining Exposure Time in Part 1, to learn how to set up a test exposure to determine both the ideal length of time to expose your solar plate and the ideal distance to leave between your solar plate and the light source. [1] Conduct a real exposure. Create your final solar-plate mold using the same process as in your test exposure and under the conditions you determined were ideal. Post-expose the solar-plate mold. Post-exposure will dry and harden your solar-plate mold all the way through. After the real exposure, wash the plate, dry the plate, and expose it under ideal conditions again. Or, put the plate in a sunny spot for about an hour. The plate is now ready for use as a mold. [2] Make the impression. Lightly coat your work surface and acrylic roller with olive oil. Roll 16g of metal clay to 5 playing cards thick (about 1.5mm) and large enough to fit your solar plate s design. Lightly brush your solar plate with olive oil, and apply a coat of natural hand balm to the clay slab. Press the clay into the plate. Ease the clay out carefully, gently lifting from all sides to avoid trapping any clay in the design lines. Trim the clay to shape with a craft knife, and clean up any nicks or dings with a damp brush. Store the excess clay, and dry the piece thoroughly. [3] Clean up the design. When the clay is totally dry, perfect the design lines using a craft knife or needle file. Smooth the outside edges and back of the piece with sandpaper, starting with 400 grit, followed by 800 and You can even carve lines into the back to echo the design of the front. Wipe over the finely sanded, finished piece with a moist towelette. This will give 50

7 3 the piece a very fine finish without weakening it. [4] Attach a bail. Cut a long, narrow strip of metal clay paper, and wrap it around a thin straw or skewer once. Apply a thin layer of metal clay paste or white wood glue to the outside of the strip, and wrap the strip around again so you have a double thickness around the straw. Trim the strip with a craft knife, and smooth the seam and sides. Slide the strip off the straw, and paste or glue it to the top back of the pendant. Paper clay doesn t dry out with normal air exposure, so as soon as the paste or glue is dry, the pendant will be ready for firing. Fire, brush, and tumble. Fire the pendant according to the metal clay manufacturer s instructions. Firing it hotter and longer will create a stronger piece (only for plain metal clay without glass or stone inclusions). Once cool, brush the fired pendant with a stainless steel brush, then tumble it for up to 2 hours until it has a bright shine. This will maximize the reflection of the silver through the transparent enamel. [5 6] Enamel the pendant. See Safety First! right, before using enamels. Select your powdered enamel colors. Place 1 2 teaspoon (2.5mL) of each color in a small, individual plastic cup. Wash (also referred to as rinse ) the enamels by using a pipette or dropper to add enough water to each cup to cover the surface of the enamel. You can also hold the cup under a gentle stream of cold tap water. (If tap-water quality is poor in your area, use distilled water.) Swish the water around until it becomes cloudy, and carefully pour it out. This removes the fine, dusty enamel particles and leaves the heavier ones in the cup. Repeat, washing your enamels until the water runs clear. Transfer the damp enamels to a palette if desired. Put a thin layer of damp enamels into the cells of the pendant [5], then let them dry [6]. For tips on applying thin enamel layers, see Think Thin, right. [7] Fire the enamel. Heat the kiln to 1500 F (816 C), and keep it there for the duration of your enameling. Put the enameled pendant into the hot kiln on a trivet [7], and fire it until the enamel looks nearly smooth only about 1 minute. You can use a timer, but always look to see that the enamel has smoothed out. think thin An easy way to get thin and even enamel layers is to put a few extra drops of water in the cell you are working in. This will allow you to float the enamel particles in place without forming bumps and hollows. When the first layer of enamel is in place, use a large, damp brush to gently wick away the excess water to reduce the drying time. Use a damp brush to remove every last grain of enamel from the silver areas; these stray grains will burn hard onto the silver during firing and are very difficult to remove later. Applying thin layers makes blending colors through successive layers easier. Enamels work like watercolor paints if you put blue on top of fired yellow, the result will be a shade of green, and so on. safetyfirst! When handling any enamel powders, wear a good-quality dust mask and work in a well-ventilated area. Both unleaded and leaded enamels are dangerous to breathe. Fine enamel particles become airborne while you work with them and are a serious health risk when inhaled. Wash your powdered enamel colors (also called rinsing ) to remove the fine dust particles and leave behind heavier particles that will not become airborne (see steps 6 7). This is a much safer process than sifting. Washing the enamels also makes them more transparent, which is usually desirable in enameled jewelry. 51

8 7 8 9 Take the pendant out of the hot kiln using a barbeque slide or an enameling fork, and place the hot pendant on top of the kiln where it can slowly cool. It is very important to keep the pendant away from drafts to avoid cracking. Once the enamel has cooled, apply another thin layer and fire again. Repeat until the last coat of enamel that has been fired is level with the top surface of the pendant. [8 9] Apply a counterenamel, and fire. After you ve enameled the front of the pendant, use the same procedure to apply three to five thin layers of counterenamel to the back, whether the back is carved or unleaded or leaded? There are trade-offs when using either unleaded or leaded enamels. Unleaded enamels don t pose as much of a health risk as leaded enamels. Lead is an accumulative poison, and its safe handling is imperative. If you re working with enamels for the first time, or with children, never use leaded enamels. If you are more experienced, leaded enamels will give clarity not. This will even out pressures between the metal and the glass, making the enamel stable and less likely to crack. Because the front of the piece is enameled, you can t put the pendant face down on a trivet again. You ll have to support the piece in a way that ensures that none of the previously enameled surfaces will be touching the trivet. Try creating steel trees that can bend to support your pendant [8]. Fire each counterenamel layer for about 1 minute. Traditionally, counterenamel is applied only to areas of the back that mirror the enameled areas of the front. The color(s) to use for the counterenamel are optional; and brilliance unmatched by unleaded enamels. Unleaded and leaded enamels can be used together in one piece, but unleaded enamels must always go underneath leaded enamels. Also, make sure the enamels you choose are suitable for use on silver; ask your supplier especially regarding reds, yellows, and pinks. however, using the same colors as on the front will give you the best results because the expansion rate of the enamels will be exactly the same [9]. Grind the finished enamel. Some prefer the natural enameled look, with its slightly rippled appearance; others prefer to stone the enamel. Stoning is traditionally done by rubbing an alundum stone back and forth over the surface of the fired enamel under a stream of faucet water. Alternatively, try using progressively finer grades of diamond files with a little water. If using files and water, work the files over the enamel as well as the silver to get a seamless, inlaid look. It is very important to finish with a superfine-grade file so that bits of enamel don t creep into coarsegrade grooves in the silver during firing and blur your nice crisp lines. When the filing is finished, wash the piece under running water with a fiberglass brush. This will remove any loose particles that may otherwise fire into the enamel s surface. Dry the piece. Fire again and polish. Place the piece back on a trivet tree, and fire it again for about 1 minute; this will put the shine back on the enamel surface. Set the piece on top of the kiln to cool slowly. Then, polish the silver to a nice shine using a polishing cloth, burnishing tool, or flex shaft with a polishing attachment. 52