Direct Digital Wedding Rings

If you’re into highly detailed, complex forms you’ll probably need some experience using sophisticated software, but for simpler shapes you can even use the free Google SketchUp. There are many CAD platforms out there, some of them specifically for jewelry design. I chose SolidWorks because it’s what I use every day.

Each metal has a different shrinkage rate, so the last operation you do in the CAD process should be to scale the design to account for shrinkage. The casting house you choose may use a custom-formulated metal, so ask them what the shrinkage will be.

Once the design is done and scaled, output it to whatever file format your 3D printing house needs. Typically this is an STL file, but not always. The printing house will let you know what they need.

Then wait for the 3D wax prints to show up in the mail. Choose a place with a machine that’s designed specifically for direct lost wax casting. I wasted a bunch of money having the designs printed in a plastic material that I was told could be burned out of the investment (the mold) directly.

This may work for some metals, but for platinum it produced unusable parts with air bubbles. In the end, I went with a high-precision wax printer designed specifically for jewelry casting.

If you’re a hobbyist jewelry maker, you may be able to cast the rings yourself. Not having a metal foundry in my closet, I chose Platina Casting in New York to cast them in platinum.

You’ll pay for a little bit of extra material in the form of a sprue attached to the design. This is where the molten metal enters the mold cavity. The caster will cut the sprue as close as possible, but a bit will remain that will contribute to the total weight. The sprue will be sanded off during the finishing process.

Or have a professional jeweler do it for you. Since I was having stones set, I chose the latter. Stone setting is a complex task better left to the professionals.

For my final file output, I filled in the area where the stones would be except for a small hole to locate the center. This step was recommended by the jeweler who did the stone setting.

Stone setters have special tools to create the correct hole shape for each specific stone. Trying to predict these shapes before shrinkage is risky and could leave you with not enough material. Better to leave some extra for the setter to work with.

Inside sharp corners are almost impossible to polish. Even the small raised areas around the holes in my ring had this problem. Making separate parts that can be soldered together after polishing, or even adding small fillets to inside corners, can help.