Carving a Bezel Setting in Wax

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In this post I want to show the first steps in making a ring with a bezel setting for a 5.5 mm square cushion cut Moissanite. The image below is a rendering done in CAD that shows the simple design for this ring setting. The setting "grows" out of the ring shank in a fluid, blended movement. Wax carving is a great way to archive those blended transitions between shapes as the wax can be sculpted and carved. It would be way harder to do the same by fabricating the ring in metal or would mean grinding lot's of metal away. It's way easier to sculpt something in wax than it is in precious metal.


A bezel setting is a very secure setting type for a gem stone. It has a metal rim that encircles the sides of a gemstone and extends slightly above it. The rim, or collar, in a full bezel stretches around the gem's entire circumference. Variations are possible by removing parts of the rim to create half bezels or other similar setting designs.


I start most of my ring carvings by slicing off a section from a wax rod with a back saw in a miter box. The thickness of the band gets marked on the rod by scraping a line with dividers. At this point I rather make the slice a bit thicker than required. Excess wax can easily be removed later. The wax rods come in various sizes and different shapes.

Various carving wax rod shapes
For this size 5 ring I chose a the smallest rod with the center hole. It's the closest shape to the section of the ring band (disregarding the setting). For larger man's ring I usually use the thicker rod, for more sculpted rings with a heavier top section one of the other shapes with the off center hole. I usually work with the blue carving wax as it has great flexibility. But the green or red Matt carving waxes would work too. I never use Wolf carving waxes, but I imagine they are quite similar.

The center hole will then get enlarged to the appropriate ring size by using ring tube sizer, a wooden mandrel with a sharp steel blade. The sharp blade cleanly shaves the inner wall, enlarging wax rings and leaving an even, smooth finish. Then the outer side can be filed down if required or this also can be done at a later stage especially if the band will have a rounded shank and varying width and shapes.

Matt Mini lath on Foredom Flex shaft with mounted wax rod.
An alternate approach would be using a lath to create the shank.


Wax shank blank and cushion Moissanite gem mounted on a sticky wax holder.
Next I start with modeling the setting to the shank blank. The gem stone gets placed on the shank by using a tiny amount of soft sticky wax like brown crystalline wax. The brown wax allows to adjust the placement making sure the stone being centered on the shank and the table to be totally square and not tilted.


If the stone needs to go a bit deeper in the shank, either a small hole gets drilled into the wax and the stone placed in that with it's pointed underside. Or I heat the wax blank where the stone gets placed with the tip of my electric wax pen and just press the stone into this liquid setting bed. Check carefully that the stone is positioned centered and not crocked to one side.

The carving technique I use is a mix of subtractive (carving excess wax away) and additive technique (dropping tiny amounts of liquid wax on to the design). For adding wax, a electric wax pen comes in handy. The added wax is the same type as the carving wax, I use scraps and shavings from previous works. The electric wax pen I use has different temperature settings and a foot control paddle that allows me to vary the amount of heat very well and get the wax in the right consistency. A dental pick heated over an alcohol lamp or torch could be used too but it's pretty hard to get the temperatures right (I never got it to work). Some wax pens like those battery operated thingies don't get hot enough to melt carving wax. The proper temperature is between smoke and stringy wax. If the molten wax starts smoking, it's too hot. If the wax is stringy and mixed with air bubbles, the wax pen is too cool. Find the correct temperature for the task and build up the wax until you have enough. You can always add more or carve it away later.


Here I started adding liquid carving wax all around the stone, letting it flow a bit over the rim  and higher than the table of the gem. Dripping very liquid wax under the girdle of the stone will give a perfect seat. I also added more onto the shank area around the stone and create a blending surface. With a wax pen I pick up tiny amounts of wax and let them become liquid enough to form a drop. This picture shows the setting being built up, but the surface is still lumpy. It is crucial to check for air bubbles trapped below the surface and removing them before proceeding to the next step.

Rough carving of the setting

Then I start carving the lumpy surface to create a shape that is close to the final setting, blending the side walls to the ring shank. I use various wax files, scrapers, X-acto knife, 3M medium sanding sponges etc. If too much wax gets filed away, additional wax can just be added using the additive technique. Wait a minute to let it cool and harden before filing again. All this is a very meditative process for me. One can't rush trough it but needs to go with the flow, often stopping for a bit to let the wax cool before adding more.

Wax working tools

For removing large bulks of wax on a band I use cylinder burrs with my flex shaft, adjusting carefully the speed and pressure. It just needs a light touch to carve the wax away. Don't let the bur get hot to start melting the wax. Round wax burs are great for hollowing out shanks on the underside or opening up a hole under the gem stone.

With tip of a knife I carefully cut the excess wax away from the top of the stone exposing the girdle of the gem. Be careful not to scratch a gem stone when working with softer gems.
Once the wax on the top of the gem is removed the stone needs to get taken out of the setting to make adjustments to the seat. If a hole was drilled in the beginning before placing the gem on the shank, one can just use a wooden tooth pick and push the stone from the underside gently out of the setting. If there is no hole, carefully create one by rotating a small bur, carver or needle file by hand and slowly remove a small portion of the wax under the gem stone point. Once wax film is really thin push with a wooded tooth pick as not to damage the fragile tip of the gem.

Then examine the inside of the setting and make adjustments to the wall and seat as required. This is the most tedious part. One needs to check the seat often to make sure all is even. The gem needs to easily be placed and removed from the seat. Carve side walls inside away to create a upright wall that later can be pushed over the stone girdle. The side wall needs to be higher than the girdle. Keep shrinkage during the casting process in mind. The cast ring will be about 2% smaller than the original wax model. Also remember that wax has some spring and elasticity while metal is stiff. If a stone fits in the wax setting, it might be too large once the ring is cast in metal. However, it is possible to remove metal after the casting with burs and gravers, but it's not possible to add more metal. It takes lot's of trial and error to find the right balance of what needs to get done in wax and what is better adjusted in metal.

I check the model often by holding it against a light. The thinner the wax is the more translucent it gets. It's a great way to see if there are any areas that are too thin or to heavy. Carve as necessary or add more wax and smooth it out again. If there is a crack, a pit, air bubbles or a scratch it will show up in the casting too. Any imperfections in the wax model translate into metal casting. The wax surface gets smoothed by moving through various stages of  3M polishing pads, smoothing more with a felt stick and some wax solvent rubbed over the wax with a piece o a nylon hose. The smoother the wax, the faster the clean-up in metal will be.

Ring wax models mounted on flask bottoms to be prepared for casting

Once the wax model is weighted it gets prepared for casting and mounted on sprues (gates). Then placed on rubber flask bottoms. All models placed in the same flask will get cast in the same metal. A stainless steel pipe section gets placed over the models and filled with a investment plaster. Once it sets and hardens, it gets placed in a kiln for multiple hours until the wax is all burned away leaving a hollow space in the investment plaster.

Casting flask in the burn-out kiln.

During the actual casting liquid hot precious metal will fill that hollow space, creating a slightly shrunken replica of the previous wax model. Then a lot more work is needed on the metal pieces before the final ring is done.

This wax carving technique I use is great for creating settings for unusual shaped, non-round stones. It can be used on round gems too. Round settings are the easiest to create as wax burs and other rotary tools can be used to easily carve a perfect seat for the faceted gem. It is tougher to create settings for stones with corners, fancy or uneven cuts. By adding wax directly to the gem stone, the stone basically become the mold for the setting, getting a perfect shape faster than by just carving it out of a block of wax. Be careful when using this technique on soft and heat sensitive stones. Sometimes it's better for those to either use waxes that have a lower melting temperature than carving waxes or use a different technique all together.  A great tutorial of a built-up setting for a shell can be found here. A wax carving book I would recommend is: Basic Wax Modeling: An Adventure in Creativity byHiroshi Tsuyuki. Lot's of great step by step wax techniques are shown. Kate Wolf's wax working work shops are also known to be great.

Wax carving is a fun process and has almost unlimited design possibilities.








2 comments:

Anonymous said...

i need some wax models

Jenny Saunder said...

nice post sharing information related to foredom flexshaft

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