Professional Jeweler Archive: Manufacturing a Pearl & Diamond Pendant

September 2003

Professional Bench/Welding Technologies

Manufacturing a Pearl & Diamond Pendant

Knowing how to use tack and pulse-arc welding for this project saves time, increases quality and drives up profits for your shop and service department

The karat gold pendant calls for several solder joints in close proximity. To facilitate the assembly, I tack-and/or pulse-arc welded the parts before soldering to eliminate shifting or dropping off during the soldering process. The tack-welding also facilitated my ability to easily make adjustments for alignment. Here’s how:

This pendant is being constructed from two 14k yellow gold cast pieces. Also shown are six 14k white gold settings, small diamonds, jump ring attachments and three freshwater cultured pearls.
Prefinish and prepolish the rough castings and prepare them for assembly by notching (red arrows indicate notched areas). Using firm pressure, I tack-weld the two cast pieces. For tack-welding, I set the ABI Tack II tack welder to 50 volts on the high energy setting. If an alignment change is needed, the two pieces will come apart easily.
No further adjustments are required. Because the two pieces are heavy, additional welding is required to hold them together during the soldering process. I use the ABI Pulse-arc welder to strengthen the tack-welded joints. For this step, I set the Pulse-arc welder to 50 volts on the high energy setting using #2 tip. The two pieces are attached permanently, and soldering will complete the assembly.
I solder the two pieces using 14k yellow easy solder, then use a small ball bur to notch the pendant at each location for the settings. With the tack-welder set to 40 volts on the high energy setting, I tack the six settings in place. Removing settings that aren’t aligned properly requires just light finger pressure before re-tack-welding.
I solder the settings using 14k yellow easy solder. Because they are tack-welded into location, no additional holding devices or heat sinks are required for the soldering procedure. Previously soldered pieces couldn’t shift.
Next I file one flat side on each jump ring away from the joint. Then I tack-weld the jump rings on each side of the top where the chain will be attached and one for the pearl that will dangle from the bottom of the design. For these pieces, I set the tack-welder to 30 volts on the high energy setting. After the tack welding is complete, I solder each one with 14k yellow easy solder. As the last step (not shown) I tack-weld then soldered the two pearl posts.

NOTE: During the soldering procedure, because the solder joints are very close together, they reach the proper temperature to activate and allow pieces to drop off. They do not drop off, however, thanks to tack-welding before soldering. I don’t need heat sinks or holding devices, and soldering is simple.

This photograph shows the completed assembly ready for setting, finishing and installation of the chain.

After the diamonds are set, I finish the piece and install the chain. Red arrows indicate where jump rings are pulse-arc-welded closed. No damage to the pearl or chain occurs, and only very minor finishing is required in these three areas. For the pulse-arc welding, I use the smallest tip on the weld pencil and set the unit to 25 volts on the low energy setting.

Because of multiple small parts in close proximity, tack and pulse-arc welding make this assembly quick and simple. Tack and pulse-arc welding also allows me to use the torch less, minimizing oxidation, making cleanup more efficient.

Important: All tack-, fusion- and pulse-arc equipment settings will differ and are based on the volume, amount of contact and alloy of the material you assemble. Working with like materials gives you a parameter for the settings required for your application. Keep a record of settings and tasks for future reference.

– by Mark B. Mann

For questions on this process, contact Mark B. Mann at markbmann@ or (406) 961-4426. This installment on welding technologies is sponsored by ABI, Cranston, RI.

For general information on ABI equipment and procedures or for a list of distributors, call Janet Kirk at (888) 494-2663.

Photographs by Mark B. Mann
©2003 Visual Communications

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