Thursday, December 30, 2010

How it is made: A custom wedding ring for an old engagement ring. Part 3.

The last part.

The benchpin is probably the most ingenious and usable tool in a jewelry studio. I discover a new use for it everyday. This time I realized that I can use it to hold the freshly attached sprue upside down, squeezed into the benchpin's slot and work on the other end, until the wax at the ring shank completely solidifies. The shank affixed to the sprue, then can be united with the head. After smoothing the welding area , I removed the little bridge between the two shanks, that helped me to prevent breaking the delicate wax structure.. Holding the wax against a light source, allows me to judge the thickness and evenness of the whole contraption, last time before casting, and make some last minute adjustments if needed.

The wax model is then completed with sprues, that will allow the molten metal fill the mold. The models are attached to a rubber base and the whole "tree' is embedded into a plaster like material, called investment. The investment is placed into a furnace to make the plaster hard and melt the encased wax out of it; hence the name of "lost wax casting" . The wax leaves a cavity system inside the hardened investment and provides a mold for the molten metal. After about 8 hours of firing , all residues of the wax are burned out of the mold and it is ready for casting. After casting the rings, the investment material is removed (white stuff on the picture )  and the the result becomes visible. This is the moment of truth. This is the moment, when it turns out whether or not the work of many hours is resulted in a good casting, or have to be started over.

The rest of the process is only briefly summarized here: After the castings were cut off the tree, the engagement ring was fitted and soldered to the guard/wedding ring. The surfaces were filed and  sanded and polished until they took on the desired final finish. Then I set the raw diamond cubes and made some final touch up on the surfaces. The ring is  finished and ready to be shipped. In this setting , the weak parts of the old ring are fortified and the diamond is protected from the majority of blows, that are also the most dangerous : the sideways hits.

The finished wedding suit. I used a similar process for the groom's wedding band.

1 comment:

  1. So interesting to see your process, thank you. The ring is beautiful.