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Old 02-15-2011, 02:29 PM
Jeffrey Jeffrey is offline
Steel
 
Join Date: Dec 2010
Location: Corvallis Oregon
Posts: 70
Default Re: Looking for help from Jewelers. Repair gone bad!!

Hi Turtle

Sorry I missed this post, I've been busy at the bench for the last few days. So sorry about the turquoise, and your customer is a real gem! Just for informations sake, I'll relate how I usually handle soldering silver, especially when a gem is present, as I've done a lot of this kind of work over the years while running a trade shop.

For silver repairs on a heavy piece with a stone present, I exclusively use acetylene/oxygen with a larger single orifice torch, definitely not a mini of any kind but rather the size of a small-medium size casting torch. The trick is to get in and out extremely fast by using a very hot and sharp flame. Since silver is super-conductive to heat, you have to overpower the heat conductance with the amount of energy you're pouring into the silver with the torch. To protect the stone I use sopping wet paper towel generously wrapped around the stone area and keep a bowl of water very close by to immediately dip the freshly soldered piece into. The heat resistant compounds you can purchase don't work so well with silver as they can't be refreshed like water-soaked paper towel can. I haven't lost a stone yet this way, but it takes some practice to not melt the jewelry item. If you have to solder close to the stone then you'll have to take out the stone or use a powerful laser welder. One of the new electric welder (like a PUK) might work as well but I have no experience welding silver with one. I have welded prongs onto a very expensive and large emerald with one though, they work very well. The down side with electric welders is they blast through very thin metal. By the way, once a turquoise is heated enough to damage it, the color changes as I'm sure you noticed, and it becomes quite brittle, that's my personal experience anyway.

On a side note, I'd veer away from using any gas/air setup, it's just not hot enough for most jewelry work, although I've known jewelers that cast this way. While propane/oxygen is not the best setup, it's probably the most commonly used other than natural gas/oxygen. I personally think the very best setup is hydrogen/oxygen, but most will probably not agree with me for various reasons. For casting, Hydrogen/oxygen is definitely the best if you must use torch melting. Sorry to go off on a tangent, once I get going on this subject it's hard for me to stop

I'm always happy, if I'm able, to answer any questions or offer any advice related to jewelry making or stone setting. I worked in or ran jewelry trade shops for about 40 years and have seen a lot of what comes through trade shops. The jewelry trade is simply amazing. No one can learn everything there is to know as jewelry work derives from so many related fields. I once got a chance to closely examine some exquisite jewelry made at the pre-Bolshevik workshop of Fabrege' in Russia that made me feel like a fledgeling apprentice again!
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