QuestionDr Roark, I have a 925 silver ring set with macasite stones. It is an old ring and the shank has broken so it is now in two pieces. I would like to reshank the ring with new 925 and is this possible using Technoflux paste to protect the stones? I am reluctant to try this without advice.
Thankyou for your time,
Suzie
AnswerHello Suzie,
I think Technoflux is an Otto Frei product for fixturing- it will probably work, though I prefer wet wadded newsprint over most of the thermal pastes out there- Vigor makes one that is both hard to find now and great, but you have technoflux..so if its anything like "cool jool"- retun it! It is the worst thermal product i have ever used- it is gel- like and neon pink- i have not seen the actual technoflux contents but if Otto Frei sells it, it may be usable... Rio Grande sells Cool Jool- and it is pure junk so you can't just trust a supplier's catalogue!...I would protect the stones though with some wet wadded newsprint or welding supply grade thermal paste ( newsprint actually works better; have it wet enough and wadded enough that it isn't running all over your soldering board, and just arrange the mass all around the stones if its the right consistency it'll stick-welding supplies sell the paste much like Vigor's " heat shield" brand, but far cheaper than at any jewelry supplier's . If you have a ton of craft supplies around go thorough your stash for some instant papier mache mix- if not there is a product on the market for many years called "Cell-u-Clay" its an instant papier mache mix, in a block form and quite cheap- just reseal in a zipper lock or vac-u-seal bag for storage once opened- just wet a bit of that in a paper cup or other small container and use it to protect even diamonds- works fabulously!)and then just flux solder and pickle.
Then finish as you will.
I personally would use hard .925 solder though in wire or paillion whichever you
A) have on hand and
B) are more comfortable with. if so stick with some regular hard solder -
Perhaps you could do an experiment on a set stone piece (that is also broken) and is is equivalent to the marcasites using your technoflux- If you have already purchased it..
If not go for the wadding or mache' mix..in the long run it protects diamonds in my experience and outperforms most of the thermal shields out there-
Some are simply green clay and water- they dry with prolonged or oxy/fuel torches and break off just as the metal comes to temperature to flow the solder- cool jool didn't even stay on that long! The marcasites are not that hard ( on the moh's scale) so they do require protection, and if you use the old fashioned stop flow of yellow ochre, I'm afraid it won't give enough protection as the band may heat more than the stones can take with the fluidity of yellow ochre and water- better is the wadding, and regular hard, or med. hard solder ( if all you have on hand though is repair solder you can use it- no need in wasting supplies on hand already!).I wish I had some technoflux experience- I'm glad I at least know what it is..but afraid I haven't used it as I always have newsprint on hand and have used it for many many years..
Best regards Ari
