Torch re-tipping versus laser welding
I became a bench jeweller in the dark ages, when laser welders were not part of the landscape. (Okay, I’m exaggerating to make a point.) Back then, one of our main concerns was ‘fixturing’ the piece we were working on. The tool in the first photo above has two tweezer arms and works great for holding a ring in one and a wire in the other. When re-tipping a ring with a gallery, I bend the new prong wire so that it wraps around the worn out prong. This way, I can build it up below the girdle line, as well as on top of the stone.
When re-tipping, I always use a good-quality hard solder. An easy-flow solder pits more easily and tends to run into areas where it shouldn’t. Since the ring in our example was originally cast and has no previous solder seam, I was able to use 14-kart hard plumb solder.
Re-tipping a prong with solder only rather than also adding new metal, is a huge mistake. Doing so creates a weak—and often pitted—prong. It is a sure sign of poor craftsmanship and is unacceptable.
A prong re-tipped using a torch requires time and effort to become a thing of beauty. The wire I soldered onto this prong was larger than needed, so the excess metal will need to be filed down to the correct size. The trick to a great re-tipping job is to blend the new metal into the old prong and make it look like a whole new piece. When re-tipping using a torch, I can generally do five to six prongs in an hour’s time and maintain a high level of quality.
To provide an example for this article, I re-tipped half the prongs on this same ring using a laser welder. The difference is phenomenal. A laser welder is a fantastic tool for re-tipping, as you can add metal with pinpoint accuracy. When working on a rounded prong, I expand the laser beam’s diameter and diminish its voltage, lessening the unsightly dimpling normal to a laser weld.
The front prong seen in the photo in the top left has been completely rebuilt using a laser. For comparison’s sake, I only repaired the tip on the right side and still have a bit of work to do in the lower gallery area of this prong. With a laser, you can actually shape the metal as it is being added. This greatly reduces the amount of metal used and speeds up the time needed to blend and shape the new prong. I can also re-tip twice as many prongs in the time it would take to torch-solder them. At our store, we charge the same for laser or torch re-tipping. The extra profit from the laser goes to pay for the machine.
As you can see in the last photo above, the end result turned out well. The new prong tips are all blended as they should be and appear as if they were original to the piece. The front side of the ring was re-tipped using a laser welder, while the prongs on the far side were all torch re-tipped. Regardless of the tool used, the outcome should be the same.
