By Tom Weishaar
Editor’s Note: This is the third installment in a six-part series that aims to break bad habits and do away with shortcuts bench jewellers often pick up. This time, we turn our attention to re-tipping versus reconstructing.
One of my personal heroes is Mike Holmes, the home repair guru whose television program, Holmes on Homes, depicts poor renovation projects he makes right for the homeowner. Mike has made a name for himself in Canada, both among the general public and in construction circles. His following in the United States is equally impressive.
You might wonder why I would make a connection between Mike Holmes and an article about re-tipping prongs. The answer is because re-tipping and reconstructing prongs are the most common repair jobs done by bench jewellers. They are also the two tasks most frequently done wrong. As Mike Holmes would say, “This is unacceptable.”
The oddity about re-tipping is it ranks among the most profitable of all repair jobs. Think of it this way—a prong usually needs to be re-tipped approximately every 10 years. There are literally millions of worn out prongs just waiting to be re-tipped at an average cost of about $15 to $20 each. No need to do the math. The answer is quite clear. From a purely financial point of view, a bench jeweller could make a lot of money if all they did was re-tip prongs and were really good at it.
That said, why is this particular repair so commonly abused? Perhaps the answer lies solely in its everyday nature. Has re-tipping become mundane, boring, not worth our time? Is this why so many bench jewellers look for shortcuts when it comes to re-tipping? What the jewellery industry needs is a Mike Holmes.
Before we go any further, I must caution you to check the condition of your boric acid solution. I’ve mentioned before this material is a deoxidizer, meaning it prevents oxygen molecules from attacking metal being soldered. In a high-oxygen environment, diamonds begin to burn or ‘frost’ at 700 C (1292 F); at lower oxygen levels, significant burning occurs at 850 C (1562 F). Boric acid coats diamonds and seals off oxygen attack. It is the only thing protecting stones during re-tipping. If you’re using old boric acid that is crystallized like the solution in the second and third photos above, it needs to be changed. Remember, the beneficial effects of boric acid are burned away in one to two minutes upon applying heat.
