Setting Stones in Wax

One of the most revolutionary advances in recent years, apart from laser welding, is the method of setting stones in wax. It has allowed many previously impossible designs andalso allowed the jeweler to forge ahead and create many difficult setting projects.

This is one of the most economical methods in stone setting. It removes the high labor stone setting fees of some setting projects.

Our jewelry knowledge has exponentially increased with bench jewelers trying new. innovative ideas. Imagine a twenty minute diamond setting procedure in the traditional way in the metal; and then with this wax-set method being able to perform the same setting job in only seconds? What a cost and time saving technique!

Now let's all see how this method of setting stones in wax is done and how easy it really is.

Alter the metal designer makes his silver-model and prepares all the claws with little undercutting grooves,
he will then make the final computations for the final selection of diamonds and then makea rubber mold of his pattern. Most rubber molds have a 10% shrinkage rate. A knowledgeable jeweler must take into account this scaled down size of claws, channel settings, and bezels form the original size. Then the wax injector will use a wax that has "memory". This is when the wax is spread out with a stone enclosed, it will use this innate memory to return to its original shape.

Hand holding your waxes is not the wisest procedure to do as the heat of your fingers will distort the wax you are using. It can bend the shank after a few minutes. I always put my wax on a wooden tapered spindle. Secure this wax and hold it in your left hand (if you are right-handed). Pick up a round bur and holding it in fingers rotate the bur to clean out any left over wax fragments. Any excess wax in the stone's seat will prevent any stone from sitting in its correct place. Do not use a flex-shaft for this procedure.

Do not touch the claws with your fingers as you place your stone into the channel or claw setting. It should just slide in.

I must interject at this point that there are only certain types of gemstones that can be set in wax. Do not use aquamarine, garnets, opal, turquoise, pearls or any soft stone. Leave these to hand setting. Think of the colors of the American Flag - red, white, and blue. The only stones you can set this way are rubies (red), diamonds and cubic zirconia (white), and sapphires (blue). No other stone will withstand the heat of metal casting. In addition, there might be breakage if there are any inclusions in any of these stones.

When placing stones in wax make sure the girdles don't touch, as this will lead to a shattering of the stone during the on rush of hot gold. As the gold is entering the flask the sudden rush of gold will disturb the stone in the investment and jar it a bit loose. The two stones banging into each other could break both of them.

When inserting the stone into the seat, you will see the claws spread out and return again to their original position. This should take no effort. If for any reason you feel that the claw tip is not strong enough, or not to your liking, you should carefully apply some wax to any partof the claw tip. This will provide more security for the stone when it is cast in gold.

This can be done with your wax melting machine, turned on to low heat. I sometimes touch the stone, only at the table. This will heat up the stone and enable it to very slowly sink further in to the wax. I prefer to have more wax holding the stone than if I were setting the same stone directly into the gold.

When channel setting in wax please make absolutely sure the stone is held into the two walls of wax. It is an embarrassment to you (and a loss of productivity) if the stone works itself loose in the final polishing. The major cause of this is from the wax not holding the stone securely. You must observe if the wax is over the girdle, notjust against it. If any wax is over the stone, rest assured this wax will then be gold.

You should also watch out for the proper spacing as you are wax setting these stones. You cannot move the stones after gold casting.

I will not attempt to delve into the casting techniques in detail in this article. Oven temperatures, cool down cycles, investment mixtures, and burning out the wax are all issues that must be addressed. In addition, rapid cooling with aid of water will fracture any stone immediately. This is even true with diamonds. In one jewelry shop, 25 carats of melee diamonds were ruined by rapidly cooling a very hot, straight from the centrifuge flask into cold water. Please allow all wax-set stones while still in their hot flask to cool down by air-cooling. You can also let the hot flask cool in an oven. Then at that time, open the flask when you are satisfied the flask is cool to the touch of your finger.

After casting, remove the investment by hand. Try not to steam out this investment; you just might blow away any small diamond that aren't held securely.

Use a magnetic tumbler to fine clean the intricate sections of the gold pattern. Check for any loose stones and use a metal pusher to tighten any claws that may not be over the crown facets of the stone. You can use your pliers to bring in the claws and cup bur as usual. File and trim to your specifications and polish. If you handle this style of settings correctly, you will save an enormous amount of time at the bench and your customer will have a ring of beauty that will last for many years.

By Gerald N. Lewy – © Bench Magazine

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BENCH Magazine is devoted to the Bench Jeweler in retail jewelry stores and small trade shops.