Project

INTERMEDIATE | METAL

Replicate to

Replicate

Bamboo

Think its cost? Think again!

Use just your bench tools to make this pendant.

by John A.Sartin

At first glance, you might think that the bamboo motif in this pendant is the result of casting. But it doesn't require casting equipment or an arrangement with a casting house to re-create the bamboo look; bench tools are enough to transform silver tubing into convincing bamboo replicas.

In this project, I'm working with sterling silver, 14k gold, and fossilized dinosaur bone to craft a pendant with a contemporary yet antique feel. If you wish to, you can also shape and polish your own cabochon focal stone, using relatively inexpensive machinery. See "Cut Your Stone/' page 45, to learn how.

part 1: Bamboo

Cut the tubing. Use a tube-cutting jig and a jeweler's saw with a 4/0 blade to cut 3 mm outside diameter (OD) tubing into 30 tubes of 12 mm (V? in.) each [1].

File the tubes. Insert a tube into the handpiece of your flex shaft. Make sure that the tube is straight and centered. Run the flex shaft at medium speed, and use a hand file to file the end of the tube square. Then tilt the file to put a slight bevel on the outer rim of the tube [2].

Repeat to file and bevel the other end of the tube. You can also use a sanding stick to sand any imperfections in the tube at this time. Repeat to file and bevel the rest of the tubes.

Flare the tubes. Secure a center punch, pointed side up, in a bench vise. Set a tube on the point. Set another center punch in the top of the tube, and apply light pressure to align the tube and punches.

Strike the top center punch with a utility hammer just hard enough to slightly flare both ends of the tube [3]. You may find this awkward at first, but you will get better with practice. Repeat to flare all the tubes [4].

Make the connector spheres. Using a round bur in your flex shaft, create round depressions that are 8-10 mm (Vie-3/* in.) across in a charcoal block.

Cut 20-gauge (0.8 mm) round sterling silver wire into 25-30 lengths of 15 mm (9/i6 in.) each. Place one of the wires across a depression in the charcoal block, and use your torch to melt the wire into the depression, creating a sphere [5]. Repeat to melt all the wires into spheres.

Make bamboo segments. File a shallow groove approximately 50 mm (2 in.) long in the charcoal block. Align four tubes in the groove, placing one connector sphere between each tube. Push the tubes and spheres together so that they're touching; the groove in the charcoal block will help keep the components straight and steady.

Solder 13 the tubes and spheres using hard solder [6]. Repeat to make a total of 6 bamboo segments with 4 tubes each, and 2 bamboo segments with 3 tubes each.

A SAFETY NOTE: Do not quench or pickle the bamboo segments! Anything that is closed on both ends is extremely hard, if not impossible, to solder completely closed, especially when using flux. Even if a component appears to be completely sealed, there are microscopic holes in the solder, due to escaping air and moisture.

Quenching or pickling the piece will cause liquid to be sucked into the cavity, in effect creating a tiny pipe bomb that will ignite the next time you touch it with a torch. The moisture in the cavity will turn to steam, expand, and, in some cases, cause the piece to explode.

Carve the bamboo segments. Support a bamboo segment on your bench pin. Using the side of a Hart bur in your flex shaft, carve striations along the length of the bamboo [7]. This will not only add texture but also clean the piece of any firescale. Repeat for the remaining bamboo segments.

► The back of this pendant showcases its detailed bamboo texture. It's hard to believe it's not cast!

Make a bezel. Using jeweler's shears, cut a strip of 30-gauge (0.26 mm) 14k gold bezel wire long enough to make a bezel for your stone □ Solder the bezel join using 14k yellow gold medium solder.

Part 2: Frame and bail

Solder the bamboo segments. Line up the bamboo segments side by side on a firebrick in a roughly oval shape. Use medium solder to solder the pieces together [1]. (The photo shows two extra two-segment pieces that I added to my panel; I found that these were not needed for the featured pendant.) Again, do not quench or pickle the assembly.

Make bail components. Bend a 20-30 mm (Vt-VA-ir.) piece of 4.5 mm OD sterling silver tubing to give it a gentle curve.

Add a backplate. Use hard silver solder to solder the gold bezel to a piece of 24-gauge (0.5 mm) sterling silver sheet that is slightly larger than the bezel [1].

Using a saw with a 4/0 saw blade, cut around the bezel as close as possible, then file the edges smooth, and polish it.

Open the back of the bezel cup by piercing a hole; this will give you access to the bamboo piece when the bezel cup is set in place.

TIP: There are several ways to curve tubing without crushing or crimping it: Pack the tube with sand or pitch; insert a lubricated smaller-diameter wire into the tube; or slide the tube into a heavy spring that "'its around it snugly. Don't hurry — curve the tubing slowly!

Cut out the bamboo panel. On scrap paper, draw an oval the size of your desired pendant and cut it out. Trace the oval onto the soldered bamboo segments Use your jeweler's saw with a 4/0 blade to cut the bamboo assembly into an oval.

Use a wire brush or a radial bristle disk in your flex shaft to clean firescale off the bamboo panel to prepare it for soldering.

Using your jeweler's saw, cut the curved tubing to about 12 mm (V? in.). Also cut a 4x4 mm (V32 x 5/32-in.) piece of 18-gauge (1.0 mm) sterling silver sheet [3].

Make a frame. Measure the circumference of the bamboo panel. Cut a 4 mm (5/32-in.) wide strip of 20-gauge (0.8 mm) 14k gold sheet to that length. Solder the strip as if it were a bezel ES using "4k yellow gold solder. Fit the frame :o the oval panel [2].

Make the bail. Using hard silver solder, attach the 4 mm p/b-in.) square piece of sterling silver to the underside of the curved tubing. File and refine the square piece as necessary, and set the bail aside.

Part4: Assembly and finishing

Solder the bamboo panel in the frame.

Solder the bamboo panel inside its 14k gold frame, using medium solder. Let the assembly air-cool, then check your solder job. Do not quench or pickle! Use a brass brush or a radial bristle disk attachment in your flex shaft to remove any firescale.

Texture the frame. To add texture to the upper edge of the gold frame, position a small chisel, stamp, or punch on the frame, and strike the small tool with a utility hammer or mallet. Repeat this texture around the frame.

Attach the bezel cup and bail to the bamboo panel. Sweat easy silver solder onto the back of the bezel cup. Place the bezel cup in position on the bamboo panel, and check how the bezel cup fits against the bamboo surface. You may need to file down some of the bamboo ribs so the cup sits level.

Set the bail in position at the top of the frame, and place pallions of 14k gold easy solder at the join. Heat the entire assembly to solder both the bezel cup and the bail.

NOTE: Simultaneously soldering the bezel cup and the bail can be tricky because of the different melting points of the gold and silver solder, but if you solder the bezel cup first and then concentrate your flame on the bail, the heat carryover will quickly increase the temperature near the bail and the solder will flow at the join.

Check the solder joins and pickle the assembly. Let the assembly air-cool, and then check all of your joins. If the joins aren't complete, clean the area with a brass brush or a bristle disk in a flex shaft and then re-solder.

Let the piece air-cool, and then, if you are confident of your solder job and are certain you are finished soldering entirely, you can pickle the assembly. After pickling, let the piece sit in a sodium bicarbonate (baking soda) solution for approximately 30 minutes to neutralize the pickle. Then soak the piece in clean water for another 30 minutes.

Patinate the pendant. Prepare a warm liver of sulfur solution according to the manufacturer's instructions. Submerge the piece until the silver turns black (the patina will not affect the gold). Remove the piece from the patina solution and rinse it well.

In a small pot (preferably an enameled pot, used only for this process), place the piece in a weak solution of a pinch or two of sodium bicarbonate in clean water, and heat the solution to boiling; allow it to boil for 5-10 minutes. Remove the piece from the solution, clean the pan, and boil the piece again in clean water for at least 5 minutes. This process will neutralize any chemicals that may yet be in place.

Complete the finishing. With a bristle disk or any fine abrasive, begin removing some of the patina from the bamboo, revealing the carved striations. Work gradually; if you remove too much and have to repatinate the piece, you will have to repeat the boiling process.

Set the stone. Once you are happy with the patina on the bamboo, set the stone in the bezel □ Apply paste wax to the pendant according to the manufacturer's instructions. Multiple layers of wax will seal and enrich the patina and enhance the texture. OS

Videos & Basics

Check out these bonus tutorials for fundamental techniques used in this project:

D Basics, page 87

□ Videos, www.artjewelrymag.

com/videos materials a Sterling silver tubing: 22-gauge (0.6 mm) wall thickness: » 3.0 mm outside diameter (OD), 38.4 cm (15 in.)

* Sterling silver sheet:

18-gauge (1.0 mm), 4x4 mm (V32 x s/i2 in.) a Sterling silver wire: 20-gauge (0.8 mm), round, 50 cm (20 in.) a 14k gold sheet: 20-gauge (0.8 mm), 4 mm (Vn in.) wide; length to fit bamboo panel (about 12 cm/5 in.) n 14k gold bezel wire: 30-gauge (0.26 mm), size to fit cabochon » 14k yellow gold solder: medium, easy

Cabochon: fossilized dinosaur bone or other, 18x11 mm pVte x 7/ie in.)

toolboxes, page 88

Soldering k Bezel setting m Sawing/piercing Finishing additional tools & supplies

« Tube-cutting jig

* Burs for flex shaft: round, Hart w Bench vise

► Utility hammer Bench vise

Wire brushes or bristle disks : Small chisel, stamp, or punch is Baking soda « Paste wax

See Supoliers, page 93 See Safety Basics, page 89

▼ A side view shows the marvelous mix of colors and textures in the finished pendant.

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