May 2003 Professional Bench/Welding Technologies Shortening an In-Line Bracelet Using Pulse-Arc Welding Techniques Knowing how to tack-, fusion- and pulse-arc-weld at the bench saves time, increases quality and boosts profits for your shop and service department This in-line bracelet needs to be shortened by two links. The bracelet is held together by a single link-wire wrapped around an open portion of the adjacent link and permanently joined, giving the bracelet maximum flexibility. Following is a procedure for shortening, reassembling and permanent welding of the link. 1. This in-line bracelet has alternating 14k yellow and white gold domed links. A 5mm lab-created moissanite is flush set in each of the white gold links. 2. Saw to remove two links. The best location for sawing is adjacent to the domed link (A). Open the links and remove the two unwanted links to shorten. 3. Reassemble the links and tighten (B) for pulse-arc welding. There’s a very small gap at the top of the joint, and it’s flush and in full contact at the bottom. 4. Position the welding pencil over the open link and depress the foot pedal. A single pulse of energy welds the link at the bottom of the joint where it was in full contact. 5. To complete the weld joint, use 28-gauge 14k white gold wire and build up the joint (C). The ABI Tack III Pulse-Arc welder is set on the high energy setting at 45 volts for steps 4 and 5. 6. Four additional pulses of energy were required with the 28-gauge wire to sufficiently build the joint (D). (See “Know Your Equipment” at right.”) 7. The surface discoloration from the pulse-arc welding process is easily removed by wire brushing. File or sand the excess metal at the joint and polish. 8. The shortening process took 12 minutes from start to finish. Important: All tack- and pulse-arc equipment settings will differ and are based on the volume and alloy of the material you’re working with. Using like materials will give you a parameter for the settings required for your application. Keep a record of settings and tasks for future reference. If you have questions about this process, contact Mark B. Mann at markbmann@aol.com. This installment is sponsored by ABI, Cranston, RI. For information related to ABI, call Janet Kirk at (888) 494-2663. Know Your Equipment The weld pencil contains an electrode (4). The electrode is inserted through the base metal housing that’s inserted in the threaded weld-pencil tip (2). A ceramic tube (3) is also inserted into the tip and secured by tightening the allen screw with the ABI-provided key-wrench (1). Over time, the electrode’s tip becomes misshapen from use. It’s best to keep it rounded at the end by sanding. While shaping the electrode, clean and shape the ceramic tip. For this procedure, the tip of the electrode is recessed 1mm inside the ceramic tube. For this pulse-arc welding procedure, the weld pencil with a #2 electrode and ceramic tip is used (1), attached to the positive lead. The contact pad is attached to the negative lead. For easiest viewing of the work-in-progress, the contact pad rests on a lowered flat bench pin. – by Mark B. Mann Photos by Mark B. Mann ©2003 Visual Communications